diff --git a/doc/descriptors.md b/doc/descriptors.md
new file mode 100644
index 000000000..9e2483192
--- /dev/null
+++ b/doc/descriptors.md
@@ -0,0 +1,109 @@
+# Support for Output Descriptors in Bitcoin ABC
+
+Since Bitcoin ABC v0.20.7, there is support for Output Descriptors in the
+`scantxoutset` RPC call. This is a simple language which can be used to
+describe collections of output scripts.
+
+This document describes the language. For the specifics on usage for scanning
+the UTXO set, see the `scantxoutset` RPC help.
+
+## Features
+
+Output descriptors currently support:
+- Pay-to-pubkey scripts (P2PK), through the `pk` function.
+- Pay-to-pubkey-hash scripts (P2PKH), through the `pkh` function.
+- Pay-to-script-hash scripts (P2SH), through the `sh` function.
+- Multisig scripts, through the `multi` function.
+- Any type of supported address through the `addr` function.
+- Raw hex scripts through the `raw` function.
+- Public keys (compressed and uncompressed) in hex notation, or BIP32 extended pubkeys with derivation paths.
+
+## Examples
+
+- `pk(0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798)` represents a P2PK output.
+- `pkh(02c6047f9441ed7d6d3045406e95c07cd85c778e4b8cef3ca7abac09b95c709ee5)` represents a P2PKH output.
+- `combo(0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798)` represents a P2PK and P2PKH output.
+- `multi(1,022f8bde4d1a07209355b4a7250a5c5128e88b84bddc619ab7cba8d569b240efe4,025cbdf0646e5db4eaa398f365f2ea7a0e3d419b7e0330e39ce92bddedcac4f9bc)` represents a bare *1-of-2* multisig.
+- `sh(multi(2,022f01e5e15cca351daff3843fb70f3c2f0a1bdd05e5af888a67784ef3e10a2a01,03acd484e2f0c7f65309ad178a9f559abde09796974c57e714c35f110dfc27ccbe))` represents a P2SH *2-of-2* multisig.
+- `pk(xpub661MyMwAqRbcFtXgS5sYJABqqG9YLmC4Q1Rdap9gSE8NqtwybGhePY2gZ29ESFjqJoCu1Rupje8YtGqsefD265TMg7usUDFdp6W1EGMcet8)` refers to a single P2PK output, using the public key part from the specified xpub.
+- `pkh(xpub68Gmy5EdvgibQVfPdqkBBCHxA5htiqg55crXYuXoQRKfDBFA1WEjWgP6LHhwBZeNK1VTsfTFUHCdrfp1bgwQ9xv5ski8PX9rL2dZXvgGDnw/1'/2)` refers to a single P2PKH output, using child key *1'/2* of the specified xpub.
+
+## Reference
+
+Descriptors consist of several types of expressions. The top level expression is always a `SCRIPT`.
+
+`SCRIPT` expressions:
+- `sh(SCRIPT)` (top level only): P2SH embed the argument.
+- `pk(KEY)` (anywhere): P2PK output for the given public key.
+- `pkh(KEY)` (anywhere): P2PKH output for the given public key (use `addr` if you only know the pubkey hash).
+- `combo(KEY)` (top level only): an alias for the collection of `pk(KEY)` and `pkh(KEY)`.
+- `multi(k,KEY_1,KEY_2,...,KEY_n)` (anywhere): k-of-n multisig script.
+- `addr(ADDR)` (top level only): the script which ADDR expands to.
+- `raw(HEX)` (top level only): the script whose hex encoding is HEX.
+
+`KEY` expressions:
+- Hex encoded public keys (66 characters starting with `02` or `03`, or 130 characters starting with `04`).
+- [WIF](https://en.bitcoin.it/wiki/Wallet_import_format) encoded private keys may be specified instead of the corresponding public key, with the same meaning.
+-`xpub` encoded extended public key or `xprv` encoded private key (as defined in [BIP 32](https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki)).
+  - Followed by zero or more `/NUM` unhardened and `/NUM'` hardened BIP32 derivation steps.
+  - Optionally followed by a single `/*` or `/*'` final step to denote all (direct) unhardened or hardened children.
+  - The usage of hardened derivation steps requires providing the private key.
+  - Instead of a `'`, the suffix `h` can be used to denote hardened derivation.
+
+`ADDR` expressions are any type of supported address:
+- P2PKH addresses (base58, of the form `1...`). Note that P2PKH addresses in descriptors cannot be used for P2PK outputs (use the `pk` function instead).
+- P2SH addresses (base58, of the form `3...`, defined in [BIP 13](https://github.com/bitcoin/bips/blob/master/bip-0013.mediawiki)).
+
+## Explanation
+
+### Single-key scripts
+
+Many single-key constructions are used in practice, generally including
+P2PK, and P2PKH. Many more combinations are imaginable, though they may
+not be optimal: P2SH-P2PK, P2SH-P2PKH.
+
+To describe these, we model these as functions. The functions `pk` (P2PK) and
+`pkh` (P2PKH) take as input a public key in hexadecimal notation (which will
+be extended later), and return the corresponding *scriptPubKey*. The functions
+`sh` (P2SH) take as input a script, and return the script describing P2SH
+outputs with the input as embedded script. The names of the functions do
+not contain "p2" for brevity.
+
+### Multisig
+
+Several pieces of software use multi-signature (multisig) scripts based
+on Bitcoin's OP_CHECKMULTISIG opcode. To support these, we introduce the
+`multi(k,key_1,key_2,...,key_n)` function. It represents a *k-of-n*
+multisig policy, where any *k* out of the *n* provided public keys must
+sign.
+
+### BIP32 derived keys and chains
+
+Most modern wallet software and hardware uses keys that are derived using
+BIP32 ("HD keys"). We support these directly by permitting strings
+consisting of an extended public key (commonly referred to as an *xpub*)
+plus derivation path anywhere a public key is expected. The derivation
+path consists of a sequence of 0 or more integers (in the range
+*0..2<sup>31</sup>-1*) each optionally followed by `'` or `h`, and
+separated by `/` characters. The string may optionally end with the
+literal `/*` or `/*'` (or `/*h`) to refer to all unhardened or hardened
+child keys instead.
+
+Whenever a public key is described using a hardened derivation step, the
+script cannot be computed without access to the corresponding private
+key.
+
+### Including private keys
+
+Often it is useful to communicate a description of scripts along with the
+necessary private keys. For this reason, anywhere a public key or xpub is
+supported, a private key in WIF format or xprv may be provided instead.
+This is useful when private keys are necessary for hardened derivation
+steps, or for dumping wallet descriptors including private key material.
+
+### Compatibility with old wallets
+
+In order to easily represent the sets of scripts currently supported by
+existing Bitcoin ABC wallets, a convenience function `combo` is provided,
+which takes as input a public key, and constructs the P2PK and P2PKH
+scripts for that key.
diff --git a/doc/release-notes.md b/doc/release-notes.md
index 3ad7ed1d2..dd0659743 100644
--- a/doc/release-notes.md
+++ b/doc/release-notes.md
@@ -1,5 +1,11 @@
 Bitcoin ABC version 0.20.7 is now available from:
 
   <https://download.bitcoinabc.org/0.20.7/>
 
 This release includes the following features and fixes:
+ - The new RPC `scantxoutset` can be used to scan the UTXO set for entries
+   that match certain output descriptors. Refer to the [output descriptors
+   reference documentation](/doc/descriptors.md) for more details. This call
+   is similar to `listunspent` but does not use a wallet, meaning that the
+   wallet can be disabled at compile or run time. This call is experimental,
+   as such, is subject to changes or removal in future releases.
diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp
index a9bfc8f38..fb53e6510 100644
--- a/src/rpc/blockchain.cpp
+++ b/src/rpc/blockchain.cpp
@@ -1,2535 +1,2535 @@
 // Copyright (c) 2010 Satoshi Nakamoto
 // Copyright (c) 2009-2016 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <rpc/blockchain.h>
 
 #include <amount.h>
 #include <chain.h>
 #include <chainparams.h>
 #include <checkpoints.h>
 #include <coins.h>
 #include <config.h>
 #include <consensus/validation.h>
 #include <core_io.h>
 #include <hash.h>
 #include <index/txindex.h>
 #include <key_io.h>
 #include <policy/policy.h>
 #include <primitives/transaction.h>
 #include <rpc/server.h>
 #include <script/descriptor.h>
 #include <streams.h>
 #include <sync.h>
 #include <txdb.h>
 #include <txmempool.h>
 #include <util/strencodings.h>
 #include <util/system.h>
 #include <validation.h>
 #include <validationinterface.h>
 #include <warnings.h>
 
 #include <boost/algorithm/string.hpp>
 #include <boost/thread/thread.hpp> // boost::thread::interrupt
 
 #include <cassert>
 #include <condition_variable>
 #include <cstdint>
 #include <mutex>
 
 struct CUpdatedBlock {
     uint256 hash;
     int height;
 };
 
 static Mutex cs_blockchange;
 static std::condition_variable cond_blockchange;
 static CUpdatedBlock latestblock;
 
 /**
  * Calculate the difficulty for a given block index.
  */
 double GetDifficulty(const CBlockIndex *blockindex) {
     assert(blockindex);
 
     int nShift = (blockindex->nBits >> 24) & 0xff;
     double dDiff = double(0x0000ffff) / double(blockindex->nBits & 0x00ffffff);
 
     while (nShift < 29) {
         dDiff *= 256.0;
         nShift++;
     }
     while (nShift > 29) {
         dDiff /= 256.0;
         nShift--;
     }
 
     return dDiff;
 }
 
 static int ComputeNextBlockAndDepth(const CBlockIndex *tip,
                                     const CBlockIndex *blockindex,
                                     const CBlockIndex *&next) {
     next = tip->GetAncestor(blockindex->nHeight + 1);
     if (next && next->pprev == blockindex) {
         return tip->nHeight - blockindex->nHeight + 1;
     }
     next = nullptr;
     return blockindex == tip ? 1 : -1;
 }
 
 UniValue blockheaderToJSON(const CBlockIndex *tip,
                            const CBlockIndex *blockindex) {
     UniValue result(UniValue::VOBJ);
     result.pushKV("hash", blockindex->GetBlockHash().GetHex());
     const CBlockIndex *pnext;
     int confirmations = ComputeNextBlockAndDepth(tip, blockindex, pnext);
     result.pushKV("confirmations", confirmations);
     result.pushKV("height", blockindex->nHeight);
     result.pushKV("version", blockindex->nVersion);
     result.pushKV("versionHex", strprintf("%08x", blockindex->nVersion));
     result.pushKV("merkleroot", blockindex->hashMerkleRoot.GetHex());
     result.pushKV("time", int64_t(blockindex->nTime));
     result.pushKV("mediantime", int64_t(blockindex->GetMedianTimePast()));
     result.pushKV("nonce", uint64_t(blockindex->nNonce));
     result.pushKV("bits", strprintf("%08x", blockindex->nBits));
     result.pushKV("difficulty", GetDifficulty(blockindex));
     result.pushKV("chainwork", blockindex->nChainWork.GetHex());
 
     if (blockindex->pprev) {
         result.pushKV("previousblockhash",
                       blockindex->pprev->GetBlockHash().GetHex());
     }
     if (pnext) {
         result.pushKV("nextblockhash", pnext->GetBlockHash().GetHex());
     }
     return result;
 }
 
 UniValue blockToJSON(const CBlock &block, const CBlockIndex *tip,
                      const CBlockIndex *blockindex, bool txDetails) {
     UniValue result(UniValue::VOBJ);
     result.pushKV("hash", blockindex->GetBlockHash().GetHex());
     const CBlockIndex *pnext;
     int confirmations = ComputeNextBlockAndDepth(tip, blockindex, pnext);
     result.pushKV("confirmations", confirmations);
     result.pushKV(
         "size", (int)::GetSerializeSize(block, SER_NETWORK, PROTOCOL_VERSION));
     result.pushKV("height", blockindex->nHeight);
     result.pushKV("version", block.nVersion);
     result.pushKV("versionHex", strprintf("%08x", block.nVersion));
     result.pushKV("merkleroot", block.hashMerkleRoot.GetHex());
     UniValue txs(UniValue::VARR);
     for (const auto &tx : block.vtx) {
         if (txDetails) {
             UniValue objTx(UniValue::VOBJ);
             TxToUniv(*tx, uint256(), objTx, true, RPCSerializationFlags());
             txs.push_back(objTx);
         } else {
             txs.push_back(tx->GetId().GetHex());
         }
     }
     result.pushKV("tx", txs);
     result.pushKV("time", block.GetBlockTime());
     result.pushKV("mediantime", int64_t(blockindex->GetMedianTimePast()));
     result.pushKV("nonce", uint64_t(block.nNonce));
     result.pushKV("bits", strprintf("%08x", block.nBits));
     result.pushKV("difficulty", GetDifficulty(blockindex));
     result.pushKV("chainwork", blockindex->nChainWork.GetHex());
 
     if (blockindex->pprev) {
         result.pushKV("previousblockhash",
                       blockindex->pprev->GetBlockHash().GetHex());
     }
     if (pnext) {
         result.pushKV("nextblockhash", pnext->GetBlockHash().GetHex());
     }
     return result;
 }
 
 static UniValue getblockcount(const Config &config,
                               const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 0) {
         throw std::runtime_error(
             "getblockcount\n"
             "\nReturns the number of blocks in the longest blockchain.\n"
             "\nResult:\n"
             "n    (numeric) The current block count\n"
             "\nExamples:\n" +
             HelpExampleCli("getblockcount", "") +
             HelpExampleRpc("getblockcount", ""));
     }
 
     LOCK(cs_main);
     return chainActive.Height();
 }
 
 static UniValue getbestblockhash(const Config &config,
                                  const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 0) {
         throw std::runtime_error(
             "getbestblockhash\n"
             "\nReturns the hash of the best (tip) block in the "
             "longest blockchain.\n"
             "\nResult:\n"
             "\"hex\"      (string) the block hash hex encoded\n"
             "\nExamples:\n" +
             HelpExampleCli("getbestblockhash", "") +
             HelpExampleRpc("getbestblockhash", ""));
     }
 
     LOCK(cs_main);
     return chainActive.Tip()->GetBlockHash().GetHex();
 }
 
 UniValue getfinalizedblockhash(const Config &config,
                                const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 0) {
         throw std::runtime_error(
             "getfinalizedblockhash\n"
             "\nReturns the hash of the currently finalized block\n"
             "\nResult:\n"
             "\"hex\"      (string) the block hash hex encoded\n");
     }
 
     LOCK(cs_main);
     const CBlockIndex *blockIndexFinalized = GetFinalizedBlock();
     if (blockIndexFinalized) {
         return blockIndexFinalized->GetBlockHash().GetHex();
     }
     return UniValue(UniValue::VSTR);
 }
 
 void RPCNotifyBlockChange(bool ibd, const CBlockIndex *pindex) {
     if (pindex) {
         std::lock_guard<std::mutex> lock(cs_blockchange);
         latestblock.hash = pindex->GetBlockHash();
         latestblock.height = pindex->nHeight;
     }
     cond_blockchange.notify_all();
 }
 
 static UniValue waitfornewblock(const Config &config,
                                 const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() > 1) {
         throw std::runtime_error(
             "waitfornewblock (timeout)\n"
             "\nWaits for a specific new block and returns "
             "useful info about it.\n"
             "\nReturns the current block on timeout or exit.\n"
             "\nArguments:\n"
             "1. timeout (int, optional, default=0) Time in "
             "milliseconds to wait for a response. 0 indicates "
             "no timeout.\n"
             "\nResult:\n"
             "{                           (json object)\n"
             "  \"hash\" : {       (string) The blockhash\n"
             "  \"height\" : {     (int) Block height\n"
             "}\n"
             "\nExamples:\n" +
             HelpExampleCli("waitfornewblock", "1000") +
             HelpExampleRpc("waitfornewblock", "1000"));
     }
 
     int timeout = 0;
     if (!request.params[0].isNull()) {
         timeout = request.params[0].get_int();
     }
 
     CUpdatedBlock block;
     {
         WAIT_LOCK(cs_blockchange, lock);
         block = latestblock;
         if (timeout) {
             cond_blockchange.wait_for(
                 lock, std::chrono::milliseconds(timeout), [&block] {
                     return latestblock.height != block.height ||
                            latestblock.hash != block.hash || !IsRPCRunning();
                 });
         } else {
             cond_blockchange.wait(lock, [&block] {
                 return latestblock.height != block.height ||
                        latestblock.hash != block.hash || !IsRPCRunning();
             });
         }
         block = latestblock;
     }
     UniValue ret(UniValue::VOBJ);
     ret.pushKV("hash", block.hash.GetHex());
     ret.pushKV("height", block.height);
     return ret;
 }
 
 static UniValue waitforblock(const Config &config,
                              const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() < 1 ||
         request.params.size() > 2) {
         throw std::runtime_error(
             "waitforblock <blockhash> (timeout)\n"
             "\nWaits for a specific new block and returns useful info about "
             "it.\n"
             "\nReturns the current block on timeout or exit.\n"
             "\nArguments:\n"
             "1. \"blockhash\" (required, string) Block hash to wait for.\n"
             "2. timeout       (int, optional, default=0) Time in milliseconds "
             "to wait for a response. 0 indicates no timeout.\n"
             "\nResult:\n"
             "{                           (json object)\n"
             "  \"hash\" : {       (string) The blockhash\n"
             "  \"height\" : {     (int) Block height\n"
             "}\n"
             "\nExamples:\n" +
             HelpExampleCli("waitforblock", "\"0000000000079f8ef3d2c688c244eb7a4"
                                            "570b24c9ed7b4a8c619eb02596f8862\", "
                                            "1000") +
             HelpExampleRpc("waitforblock", "\"0000000000079f8ef3d2c688c244eb7a4"
                                            "570b24c9ed7b4a8c619eb02596f8862\", "
                                            "1000"));
     }
 
     int timeout = 0;
 
     uint256 hash = uint256S(request.params[0].get_str());
 
     if (!request.params[1].isNull()) {
         timeout = request.params[1].get_int();
     }
 
     CUpdatedBlock block;
     {
         WAIT_LOCK(cs_blockchange, lock);
         if (timeout) {
             cond_blockchange.wait_for(
                 lock, std::chrono::milliseconds(timeout), [&hash] {
                     return latestblock.hash == hash || !IsRPCRunning();
                 });
         } else {
             cond_blockchange.wait(lock, [&hash] {
                 return latestblock.hash == hash || !IsRPCRunning();
             });
         }
         block = latestblock;
     }
 
     UniValue ret(UniValue::VOBJ);
     ret.pushKV("hash", block.hash.GetHex());
     ret.pushKV("height", block.height);
     return ret;
 }
 
 static UniValue waitforblockheight(const Config &config,
                                    const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() < 1 ||
         request.params.size() > 2) {
         throw std::runtime_error(
             "waitforblockheight <height> (timeout)\n"
             "\nWaits for (at least) block height and returns the height and "
             "hash\n"
             "of the current tip.\n"
             "\nReturns the current block on timeout or exit.\n"
             "\nArguments:\n"
             "1. height  (required, int) Block height to wait for (int)\n"
             "2. timeout (int, optional, default=0) Time in milliseconds to "
             "wait for a response. 0 indicates no timeout.\n"
             "\nResult:\n"
             "{                           (json object)\n"
             "  \"hash\" : {       (string) The blockhash\n"
             "  \"height\" : {     (int) Block height\n"
             "}\n"
             "\nExamples:\n" +
             HelpExampleCli("waitforblockheight", "\"100\", 1000") +
             HelpExampleRpc("waitforblockheight", "\"100\", 1000"));
     }
 
     int timeout = 0;
 
     int height = request.params[0].get_int();
 
     if (!request.params[1].isNull()) {
         timeout = request.params[1].get_int();
     }
 
     CUpdatedBlock block;
     {
         WAIT_LOCK(cs_blockchange, lock);
         if (timeout) {
             cond_blockchange.wait_for(
                 lock, std::chrono::milliseconds(timeout), [&height] {
                     return latestblock.height >= height || !IsRPCRunning();
                 });
         } else {
             cond_blockchange.wait(lock, [&height] {
                 return latestblock.height >= height || !IsRPCRunning();
             });
         }
         block = latestblock;
     }
     UniValue ret(UniValue::VOBJ);
     ret.pushKV("hash", block.hash.GetHex());
     ret.pushKV("height", block.height);
     return ret;
 }
 
 static UniValue
 syncwithvalidationinterfacequeue(const Config &config,
                                  const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() > 0) {
         throw std::runtime_error(
             "syncwithvalidationinterfacequeue\n"
             "\nWaits for the validation interface queue to catch up on "
             "everything that was there when we entered this function.\n"
             "\nExamples:\n" +
             HelpExampleCli("syncwithvalidationinterfacequeue", "") +
             HelpExampleRpc("syncwithvalidationinterfacequeue", ""));
     }
     SyncWithValidationInterfaceQueue();
     return NullUniValue;
 }
 
 static UniValue getdifficulty(const Config &config,
                               const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 0) {
         throw std::runtime_error("getdifficulty\n"
                                  "\nReturns the proof-of-work difficulty as a "
                                  "multiple of the minimum difficulty.\n"
                                  "\nResult:\n"
                                  "n.nnn       (numeric) the proof-of-work "
                                  "difficulty as a multiple of the minimum "
                                  "difficulty.\n"
                                  "\nExamples:\n" +
                                  HelpExampleCli("getdifficulty", "") +
                                  HelpExampleRpc("getdifficulty", ""));
     }
 
     LOCK(cs_main);
     return GetDifficulty(chainActive.Tip());
 }
 
 static std::string EntryDescriptionString() {
     return "    \"size\" : n,             (numeric) transaction size.\n"
            "    \"fee\" : n,              (numeric) transaction fee in " +
            CURRENCY_UNIT + "(DEPRECATED)" +
            "\n"
            "    \"modifiedfee\" : n,      (numeric) transaction fee with fee "
            "deltas used for mining priority (DEPRECATED)\n"
            "    \"time\" : n,             (numeric) local time transaction "
            "entered pool in seconds since 1 Jan 1970 GMT\n"
            "    \"height\" : n,           (numeric) block height when "
            "transaction entered pool\n"
            "    \"startingpriority\" : n, (numeric) DEPRECATED. Priority when "
            "transaction entered pool\n"
            "    \"currentpriority\" : n,  (numeric) DEPRECATED. Transaction "
            "priority now\n"
            "    \"descendantcount\" : n,  (numeric) number of in-mempool "
            "descendant transactions (including this one)\n"
            "    \"descendantsize\" : n,   (numeric) virtual transaction size "
            "of in-mempool descendants (including this one)\n"
            "    \"descendantfees\" : n,   (numeric) modified fees (see above) "
            "of in-mempool descendants (including this one) (DEPRECATED)\n"
            "    \"ancestorcount\" : n,    (numeric) number of in-mempool "
            "ancestor transactions (including this one)\n"
            "    \"ancestorsize\" : n,     (numeric) virtual transaction size "
            "of in-mempool ancestors (including this one)\n"
            "    \"ancestorfees\" : n,     (numeric) modified fees (see above) "
            "of in-mempool ancestors (including this one) (DEPRECATED)\n"
            "    \"fees\" : {\n"
            "        \"base\" : n,         (numeric) transaction fee in " +
            CURRENCY_UNIT +
            "\n"
            "        \"modified\" : n,     (numeric) transaction fee with fee "
            "deltas used for mining priority in " +
            CURRENCY_UNIT +
            "\n"
            "        \"ancestor\" : n,     (numeric) modified fees (see above) "
            "of in-mempool ancestors (including this one) in " +
            CURRENCY_UNIT +
            "\n"
            "        \"descendant\" : n,   (numeric) modified fees (see above) "
            "of in-mempool descendants (including this one) in " +
            CURRENCY_UNIT +
            "\n"
            "    }\n"
            "    \"depends\" : [           (array) unconfirmed transactions "
            "used as inputs for this transaction\n"
            "        \"transactionid\",    (string) parent transaction id\n"
            "       ... ]\n"
            "    \"spentby\" : [           (array) unconfirmed transactions "
            "spending outputs from this transaction\n"
            "        \"transactionid\",    (string) child transaction id\n"
            "       ... ]\n";
 }
 
 static void entryToJSON(const CTxMemPool &pool, UniValue &info,
                         const CTxMemPoolEntry &e)
     EXCLUSIVE_LOCKS_REQUIRED(pool.cs) {
     AssertLockHeld(pool.cs);
 
     UniValue fees(UniValue::VOBJ);
     fees.pushKV("base", ValueFromAmount(e.GetFee()));
     fees.pushKV("modified", ValueFromAmount(e.GetModifiedFee()));
     fees.pushKV("ancestor", ValueFromAmount(e.GetModFeesWithAncestors()));
     fees.pushKV("descendant", ValueFromAmount(e.GetModFeesWithDescendants()));
     info.pushKV("fees", fees);
 
     info.pushKV("size", (int)e.GetTxSize());
     info.pushKV("fee", ValueFromAmount(e.GetFee()));
     info.pushKV("modifiedfee", ValueFromAmount(e.GetModifiedFee()));
     info.pushKV("time", e.GetTime());
     info.pushKV("height", (int)e.GetHeight());
     info.pushKV("startingpriority", e.GetPriority(e.GetHeight()));
     info.pushKV("currentpriority", e.GetPriority(chainActive.Height()));
     info.pushKV("descendantcount", e.GetCountWithDescendants());
     info.pushKV("descendantsize", e.GetSizeWithDescendants());
     info.pushKV("descendantfees", e.GetModFeesWithDescendants() / SATOSHI);
     info.pushKV("ancestorcount", e.GetCountWithAncestors());
     info.pushKV("ancestorsize", e.GetSizeWithAncestors());
     info.pushKV("ancestorfees", e.GetModFeesWithAncestors() / SATOSHI);
     const CTransaction &tx = e.GetTx();
     std::set<std::string> setDepends;
     for (const CTxIn &txin : tx.vin) {
         if (pool.exists(txin.prevout.GetTxId())) {
             setDepends.insert(txin.prevout.GetTxId().ToString());
         }
     }
 
     UniValue depends(UniValue::VARR);
     for (const std::string &dep : setDepends) {
         depends.push_back(dep);
     }
 
     info.pushKV("depends", depends);
 
     UniValue spent(UniValue::VARR);
     const CTxMemPool::txiter &it = pool.mapTx.find(tx.GetId());
     const CTxMemPool::setEntries &setChildren = pool.GetMemPoolChildren(it);
     for (CTxMemPool::txiter childiter : setChildren) {
         spent.push_back(childiter->GetTx().GetId().ToString());
     }
 
     info.pushKV("spentby", spent);
 }
 
 UniValue MempoolToJSON(const CTxMemPool &pool, bool verbose) {
     if (verbose) {
         LOCK(pool.cs);
         UniValue o(UniValue::VOBJ);
         for (const CTxMemPoolEntry &e : pool.mapTx) {
             const uint256 &txid = e.GetTx().GetId();
             UniValue info(UniValue::VOBJ);
             entryToJSON(pool, info, e);
             o.pushKV(txid.ToString(), info);
         }
         return o;
     } else {
         std::vector<uint256> vtxids;
         pool.queryHashes(vtxids);
 
         UniValue a(UniValue::VARR);
         for (const uint256 &txid : vtxids) {
             a.push_back(txid.ToString());
         }
 
         return a;
     }
 }
 
 static UniValue getrawmempool(const Config &config,
                               const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() > 1) {
         throw std::runtime_error(
             "getrawmempool ( verbose )\n"
             "\nReturns all transaction ids in memory pool as a json array of "
             "string transaction ids.\n"
             "\nHint: use getmempoolentry to fetch a specific transaction from "
             "the mempool.\n"
             "\nArguments:\n"
             "1. verbose (boolean, optional, default=false) True for a json "
             "object, false for array of transaction ids\n"
             "\nResult: (for verbose = false):\n"
             "[                     (json array of string)\n"
             "  \"transactionid\"     (string) The transaction id\n"
             "  ,...\n"
             "]\n"
             "\nResult: (for verbose = true):\n"
             "{                           (json object)\n"
             "  \"transactionid\" : {       (json object)\n" +
             EntryDescriptionString() +
             "  }, ...\n"
             "}\n"
             "\nExamples:\n" +
             HelpExampleCli("getrawmempool", "true") +
             HelpExampleRpc("getrawmempool", "true"));
     }
 
     bool fVerbose = false;
     if (!request.params[0].isNull()) {
         fVerbose = request.params[0].get_bool();
     }
 
     return MempoolToJSON(::g_mempool, fVerbose);
 }
 
 static UniValue getmempoolancestors(const Config &config,
                                     const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() < 1 ||
         request.params.size() > 2) {
         throw std::runtime_error(
             "getmempoolancestors txid (verbose)\n"
             "\nIf txid is in the mempool, returns all in-mempool ancestors.\n"
             "\nArguments:\n"
             "1. \"txid\"                 (string, required) The transaction id "
             "(must be in mempool)\n"
             "2. verbose                  (boolean, optional, default=false) "
             "True for a json object, false for array of transaction ids\n"
             "\nResult (for verbose=false):\n"
             "[                       (json array of strings)\n"
             "  \"transactionid\"           (string) The transaction id of an "
             "in-mempool ancestor transaction\n"
             "  ,...\n"
             "]\n"
             "\nResult (for verbose=true):\n"
             "{                           (json object)\n"
             "  \"transactionid\" : {       (json object)\n" +
             EntryDescriptionString() +
             "  }, ...\n"
             "}\n"
             "\nExamples:\n" +
             HelpExampleCli("getmempoolancestors", "\"mytxid\"") +
             HelpExampleRpc("getmempoolancestors", "\"mytxid\""));
     }
 
     bool fVerbose = false;
     if (!request.params[1].isNull()) {
         fVerbose = request.params[1].get_bool();
     }
 
     uint256 hash = ParseHashV(request.params[0], "parameter 1");
 
     LOCK(g_mempool.cs);
 
     CTxMemPool::txiter it = g_mempool.mapTx.find(hash);
     if (it == g_mempool.mapTx.end()) {
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY,
                            "Transaction not in mempool");
     }
 
     CTxMemPool::setEntries setAncestors;
     uint64_t noLimit = std::numeric_limits<uint64_t>::max();
     std::string dummy;
     g_mempool.CalculateMemPoolAncestors(*it, setAncestors, noLimit, noLimit,
                                         noLimit, noLimit, dummy, false);
 
     if (!fVerbose) {
         UniValue o(UniValue::VARR);
         for (CTxMemPool::txiter ancestorIt : setAncestors) {
             o.push_back(ancestorIt->GetTx().GetId().ToString());
         }
 
         return o;
     } else {
         UniValue o(UniValue::VOBJ);
         for (CTxMemPool::txiter ancestorIt : setAncestors) {
             const CTxMemPoolEntry &e = *ancestorIt;
             const uint256 &_hash = e.GetTx().GetId();
             UniValue info(UniValue::VOBJ);
             entryToJSON(::g_mempool, info, e);
             o.pushKV(_hash.ToString(), info);
         }
         return o;
     }
 }
 
 static UniValue getmempooldescendants(const Config &config,
                                       const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() < 1 ||
         request.params.size() > 2) {
         throw std::runtime_error(
             "getmempooldescendants txid (verbose)\n"
             "\nIf txid is in the mempool, returns all in-mempool descendants.\n"
             "\nArguments:\n"
             "1. \"txid\"                 (string, required) The transaction id "
             "(must be in mempool)\n"
             "2. verbose                  (boolean, optional, default=false) "
             "True for a json object, false for array of transaction ids\n"
             "\nResult (for verbose=false):\n"
             "[                       (json array of strings)\n"
             "  \"transactionid\"           (string) The transaction id of an "
             "in-mempool descendant transaction\n"
             "  ,...\n"
             "]\n"
             "\nResult (for verbose=true):\n"
             "{                           (json object)\n"
             "  \"transactionid\" : {       (json object)\n" +
             EntryDescriptionString() +
             "  }, ...\n"
             "}\n"
             "\nExamples:\n" +
             HelpExampleCli("getmempooldescendants", "\"mytxid\"") +
             HelpExampleRpc("getmempooldescendants", "\"mytxid\""));
     }
 
     bool fVerbose = false;
     if (!request.params[1].isNull()) {
         fVerbose = request.params[1].get_bool();
     }
 
     uint256 hash = ParseHashV(request.params[0], "parameter 1");
 
     LOCK(g_mempool.cs);
 
     CTxMemPool::txiter it = g_mempool.mapTx.find(hash);
     if (it == g_mempool.mapTx.end()) {
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY,
                            "Transaction not in mempool");
     }
 
     CTxMemPool::setEntries setDescendants;
     g_mempool.CalculateDescendants(it, setDescendants);
     // CTxMemPool::CalculateDescendants will include the given tx
     setDescendants.erase(it);
 
     if (!fVerbose) {
         UniValue o(UniValue::VARR);
         for (CTxMemPool::txiter descendantIt : setDescendants) {
             o.push_back(descendantIt->GetTx().GetId().ToString());
         }
 
         return o;
     } else {
         UniValue o(UniValue::VOBJ);
         for (CTxMemPool::txiter descendantIt : setDescendants) {
             const CTxMemPoolEntry &e = *descendantIt;
             const uint256 &_hash = e.GetTx().GetId();
             UniValue info(UniValue::VOBJ);
             entryToJSON(::g_mempool, info, e);
             o.pushKV(_hash.ToString(), info);
         }
         return o;
     }
 }
 
 static UniValue getmempoolentry(const Config &config,
                                 const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 1) {
         throw std::runtime_error(
             "getmempoolentry txid\n"
             "\nReturns mempool data for given transaction\n"
             "\nArguments:\n"
             "1. \"txid\"                   (string, required) "
             "The transaction id (must be in mempool)\n"
             "\nResult:\n"
             "{                           (json object)\n" +
             EntryDescriptionString() +
             "}\n"
             "\nExamples:\n" +
             HelpExampleCli("getmempoolentry", "\"mytxid\"") +
             HelpExampleRpc("getmempoolentry", "\"mytxid\""));
     }
 
     uint256 hash = ParseHashV(request.params[0], "parameter 1");
 
     LOCK(g_mempool.cs);
 
     CTxMemPool::txiter it = g_mempool.mapTx.find(hash);
     if (it == g_mempool.mapTx.end()) {
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY,
                            "Transaction not in mempool");
     }
 
     const CTxMemPoolEntry &e = *it;
     UniValue info(UniValue::VOBJ);
     entryToJSON(::g_mempool, info, e);
     return info;
 }
 
 static UniValue getblockhash(const Config &config,
                              const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 1) {
         throw std::runtime_error(
             "getblockhash height\n"
             "\nReturns hash of block in best-block-chain at height provided.\n"
             "\nArguments:\n"
             "1. height         (numeric, required) The height index\n"
             "\nResult:\n"
             "\"hash\"         (string) The block hash\n"
             "\nExamples:\n" +
             HelpExampleCli("getblockhash", "1000") +
             HelpExampleRpc("getblockhash", "1000"));
     }
 
     LOCK(cs_main);
 
     int nHeight = request.params[0].get_int();
     if (nHeight < 0 || nHeight > chainActive.Height()) {
         throw JSONRPCError(RPC_INVALID_PARAMETER, "Block height out of range");
     }
 
     CBlockIndex *pblockindex = chainActive[nHeight];
     return pblockindex->GetBlockHash().GetHex();
 }
 
 static UniValue getblockheader(const Config &config,
                                const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() < 1 ||
         request.params.size() > 2) {
         throw std::runtime_error(
             "getblockheader \"hash\" ( verbose )\n"
             "\nIf verbose is false, returns a string that is serialized, "
             "hex-encoded data for blockheader 'hash'.\n"
             "If verbose is true, returns an Object with information about "
             "blockheader <hash>.\n"
             "\nArguments:\n"
             "1. \"hash\"          (string, required) The block hash\n"
             "2. verbose           (boolean, optional, default=true) true for a "
             "json object, false for the hex encoded data\n"
             "\nResult (for verbose = true):\n"
             "{\n"
             "  \"hash\" : \"hash\",     (string) the block hash (same as "
             "provided)\n"
             "  \"confirmations\" : n,   (numeric) The number of confirmations, "
             "or -1 if the block is not on the main chain\n"
             "  \"height\" : n,          (numeric) The block height or index\n"
             "  \"version\" : n,         (numeric) The block version\n"
             "  \"versionHex\" : \"00000000\", (string) The block version "
             "formatted in hexadecimal\n"
             "  \"merkleroot\" : \"xxxx\", (string) The merkle root\n"
             "  \"time\" : ttt,          (numeric) The block time in seconds "
             "since epoch (Jan 1 1970 GMT)\n"
             "  \"mediantime\" : ttt,    (numeric) The median block time in "
             "seconds since epoch (Jan 1 1970 GMT)\n"
             "  \"nonce\" : n,           (numeric) The nonce\n"
             "  \"bits\" : \"1d00ffff\", (string) The bits\n"
             "  \"difficulty\" : x.xxx,  (numeric) The difficulty\n"
             "  \"chainwork\" : \"0000...1f3\"     (string) Expected number of "
             "hashes required to produce the current chain (in hex)\n"
             "  \"previousblockhash\" : \"hash\",  (string) The hash of the "
             "previous block\n"
             "  \"nextblockhash\" : \"hash\",      (string) The hash of the "
             "next block\n"
             "}\n"
             "\nResult (for verbose=false):\n"
             "\"data\"             (string) A string that is serialized, "
             "hex-encoded data for block 'hash'.\n"
             "\nExamples:\n" +
             HelpExampleCli("getblockheader", "\"00000000c937983704a73af28acdec3"
                                              "7b049d214adbda81d7e2a3dd146f6ed09"
                                              "\"") +
             HelpExampleRpc("getblockheader", "\"00000000c937983704a73af28acdec3"
                                              "7b049d214adbda81d7e2a3dd146f6ed09"
                                              "\""));
     }
 
     LOCK(cs_main);
 
     std::string strHash = request.params[0].get_str();
     uint256 hash(uint256S(strHash));
 
     bool fVerbose = true;
     if (!request.params[1].isNull()) {
         fVerbose = request.params[1].get_bool();
     }
 
     const CBlockIndex *pblockindex = LookupBlockIndex(hash);
     if (!pblockindex) {
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found");
     }
 
     if (!fVerbose) {
         CDataStream ssBlock(SER_NETWORK, PROTOCOL_VERSION);
         ssBlock << pblockindex->GetBlockHeader();
         std::string strHex = HexStr(ssBlock.begin(), ssBlock.end());
         return strHex;
     }
 
     return blockheaderToJSON(chainActive.Tip(), pblockindex);
 }
 
 static CBlock GetBlockChecked(const Config &config,
                               const CBlockIndex *pblockindex) {
     CBlock block;
     if (fHavePruned && !pblockindex->nStatus.hasData() &&
         pblockindex->nTx > 0) {
         throw JSONRPCError(RPC_MISC_ERROR, "Block not available (pruned data)");
     }
 
     if (!ReadBlockFromDisk(block, pblockindex,
                            config.GetChainParams().GetConsensus())) {
         // Block not found on disk. This could be because we have the block
         // header in our index but don't have the block (for example if a
         // non-whitelisted node sends us an unrequested long chain of valid
         // blocks, we add the headers to our index, but don't accept the block).
         throw JSONRPCError(RPC_MISC_ERROR, "Block not found on disk");
     }
 
     return block;
 }
 
 static UniValue getblock(const Config &config, const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() < 1 ||
         request.params.size() > 2) {
         throw std::runtime_error(
             "getblock \"blockhash\" ( verbosity )\n"
             "\nIf verbosity is 0 or false, returns a string that is "
             "serialized, hex-encoded data for block 'hash'.\n"
             "If verbosity is 1 or true, returns an Object with information "
             "about block <hash>.\n"
             "If verbosity is 2, returns an Object with information about block "
             "<hash> and information about each transaction.\n"
             "\nArguments:\n"
             "1. \"blockhash\"           (string, required) The block hash\n"
             "2. verbosity             (numeric, optional, default=1) 0 for "
             "hex-encoded data, 1 for a json object, and 2 for json object with "
             "transaction data\n"
             "\nResult (for verbosity = 0):\n"
             "\"data\"                   (string) A string that is serialized, "
             "hex-encoded data for block 'hash'.\n"
             "\nResult (for verbosity = 1):\n"
             "{\n"
             "  \"hash\" : \"hash\",       (string) The block hash (same as "
             "provided)\n"
             "  \"confirmations\" : n,   (numeric) The number of confirmations, "
             "or -1 if the block is not on the main chain\n"
             "  \"size\" : n,            (numeric) The block size\n"
             "  \"height\" : n,          (numeric) The block height or index\n"
             "  \"version\" : n,         (numeric) The block version\n"
             "  \"versionHex\" : \"00000000\", (string) The block version "
             "formatted in hexadecimal\n"
             "  \"merkleroot\" : \"xxxx\", (string) The merkle root\n"
             "  \"tx\" : [               (array of string) The transaction ids\n"
             "     \"transactionid\"     (string) The transaction id\n"
             "     ,...\n"
             "  ],\n"
             "  \"time\" : ttt,          (numeric) The block time in seconds "
             "since epoch (Jan 1 1970 GMT)\n"
             "  \"mediantime\" : ttt,    (numeric) The median block time in "
             "seconds since epoch (Jan 1 1970 GMT)\n"
             "  \"nonce\" : n,           (numeric) The nonce\n"
             "  \"bits\" : \"1d00ffff\",   (string) The bits\n"
             "  \"difficulty\" : x.xxx,  (numeric) The difficulty\n"
             "  \"chainwork\" : \"xxxx\",  (string) Expected number of hashes "
             "required to produce the chain up to this block (in hex)\n"
             "  \"previousblockhash\" : \"hash\",  (string) The hash of the "
             "previous block\n"
             "  \"nextblockhash\" : \"hash\"       (string) The hash of the "
             "next block\n"
             "}\n"
             "\nResult (for verbosity = 2):\n"
             "{\n"
             "  ...,                   Same output as verbosity = 1\n"
             "  \"tx\" : [               (array of Objects) The transactions in "
             "the format of the getrawtransaction RPC; different from verbosity "
             "= 1 \"tx\" result\n"
             "    ...\n"
             "  ],\n"
             "  ...                    Same output as verbosity = 1\n"
             "}\n"
             "\nExamples:\n" +
             HelpExampleCli("getblock", "\"00000000c937983704a73af28acdec37b049d"
                                        "214adbda81d7e2a3dd146f6ed09\"") +
             HelpExampleRpc("getblock", "\"00000000c937983704a73af28acdec37b049d"
                                        "214adbda81d7e2a3dd146f6ed09\""));
     }
 
     LOCK(cs_main);
 
     std::string strHash = request.params[0].get_str();
     uint256 hash(uint256S(strHash));
 
     int verbosity = 1;
     if (!request.params[1].isNull()) {
         if (request.params[1].isNum()) {
             verbosity = request.params[1].get_int();
         } else {
             verbosity = request.params[1].get_bool() ? 1 : 0;
         }
     }
 
     const CBlockIndex *pblockindex = LookupBlockIndex(hash);
     if (!pblockindex) {
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found");
     }
 
     const CBlock block = GetBlockChecked(config, pblockindex);
 
     if (verbosity <= 0) {
         CDataStream ssBlock(SER_NETWORK,
                             PROTOCOL_VERSION | RPCSerializationFlags());
         ssBlock << block;
         std::string strHex = HexStr(ssBlock.begin(), ssBlock.end());
         return strHex;
     }
 
     return blockToJSON(block, chainActive.Tip(), pblockindex, verbosity >= 2);
 }
 
 struct CCoinsStats {
     int nHeight;
     uint256 hashBlock;
     uint64_t nTransactions;
     uint64_t nTransactionOutputs;
     uint64_t nBogoSize;
     uint256 hashSerialized;
     uint64_t nDiskSize;
     Amount nTotalAmount;
 
     CCoinsStats()
         : nHeight(0), nTransactions(0), nTransactionOutputs(0), nBogoSize(0),
           nDiskSize(0), nTotalAmount() {}
 };
 
 static void ApplyStats(CCoinsStats &stats, CHashWriter &ss, const uint256 &hash,
                        const std::map<uint32_t, Coin> &outputs) {
     assert(!outputs.empty());
     ss << hash;
     ss << VARINT(outputs.begin()->second.GetHeight() * 2 +
                  outputs.begin()->second.IsCoinBase());
     stats.nTransactions++;
     for (const auto &output : outputs) {
         ss << VARINT(output.first + 1);
         ss << output.second.GetTxOut().scriptPubKey;
         ss << VARINT(output.second.GetTxOut().nValue / SATOSHI,
                      VarIntMode::NONNEGATIVE_SIGNED);
         stats.nTransactionOutputs++;
         stats.nTotalAmount += output.second.GetTxOut().nValue;
         stats.nBogoSize +=
             32 /* txid */ + 4 /* vout index */ + 4 /* height + coinbase */ +
             8 /* amount */ + 2 /* scriptPubKey len */ +
             output.second.GetTxOut().scriptPubKey.size() /* scriptPubKey */;
     }
     ss << VARINT(0u);
 }
 
 //! Calculate statistics about the unspent transaction output set
 static bool GetUTXOStats(CCoinsView *view, CCoinsStats &stats) {
     std::unique_ptr<CCoinsViewCursor> pcursor(view->Cursor());
     assert(pcursor);
 
     CHashWriter ss(SER_GETHASH, PROTOCOL_VERSION);
     stats.hashBlock = pcursor->GetBestBlock();
     {
         LOCK(cs_main);
         stats.nHeight = LookupBlockIndex(stats.hashBlock)->nHeight;
     }
     ss << stats.hashBlock;
     uint256 prevkey;
     std::map<uint32_t, Coin> outputs;
     while (pcursor->Valid()) {
         boost::this_thread::interruption_point();
         COutPoint key;
         Coin coin;
         if (pcursor->GetKey(key) && pcursor->GetValue(coin)) {
             if (!outputs.empty() && key.GetTxId() != prevkey) {
                 ApplyStats(stats, ss, prevkey, outputs);
                 outputs.clear();
             }
             prevkey = key.GetTxId();
             outputs[key.GetN()] = std::move(coin);
         } else {
             return error("%s: unable to read value", __func__);
         }
         pcursor->Next();
     }
     if (!outputs.empty()) {
         ApplyStats(stats, ss, prevkey, outputs);
     }
     stats.hashSerialized = ss.GetHash();
     stats.nDiskSize = view->EstimateSize();
     return true;
 }
 
 static UniValue pruneblockchain(const Config &config,
                                 const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 1) {
         throw std::runtime_error(
             "pruneblockchain\n"
             "\nArguments:\n"
             "1. \"height\"       (numeric, required) The block height to prune "
             "up to. May be set to a discrete height, or a unix timestamp\n"
             "                  to prune blocks whose block time is at least 2 "
             "hours older than the provided timestamp.\n"
             "\nResult:\n"
             "n    (numeric) Height of the last block pruned.\n"
             "\nExamples:\n" +
             HelpExampleCli("pruneblockchain", "1000") +
             HelpExampleRpc("pruneblockchain", "1000"));
     }
 
     if (!fPruneMode) {
         throw JSONRPCError(
             RPC_MISC_ERROR,
             "Cannot prune blocks because node is not in prune mode.");
     }
 
     LOCK(cs_main);
 
     int heightParam = request.params[0].get_int();
     if (heightParam < 0) {
         throw JSONRPCError(RPC_INVALID_PARAMETER, "Negative block height.");
     }
 
     // Height value more than a billion is too high to be a block height, and
     // too low to be a block time (corresponds to timestamp from Sep 2001).
     if (heightParam > 1000000000) {
         // Add a 2 hour buffer to include blocks which might have had old
         // timestamps
         CBlockIndex *pindex =
             chainActive.FindEarliestAtLeast(heightParam - TIMESTAMP_WINDOW);
         if (!pindex) {
             throw JSONRPCError(
                 RPC_INVALID_PARAMETER,
                 "Could not find block with at least the specified timestamp.");
         }
         heightParam = pindex->nHeight;
     }
 
     unsigned int height = (unsigned int)heightParam;
     unsigned int chainHeight = (unsigned int)chainActive.Height();
     if (chainHeight < config.GetChainParams().PruneAfterHeight()) {
         throw JSONRPCError(RPC_MISC_ERROR,
                            "Blockchain is too short for pruning.");
     } else if (height > chainHeight) {
         throw JSONRPCError(
             RPC_INVALID_PARAMETER,
             "Blockchain is shorter than the attempted prune height.");
     } else if (height > chainHeight - MIN_BLOCKS_TO_KEEP) {
         LogPrint(BCLog::RPC, "Attempt to prune blocks close to the tip. "
                              "Retaining the minimum number of blocks.\n");
         height = chainHeight - MIN_BLOCKS_TO_KEEP;
     }
 
     PruneBlockFilesManual(height);
     return uint64_t(height);
 }
 
 static UniValue gettxoutsetinfo(const Config &config,
                                 const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 0) {
         throw std::runtime_error(
             "gettxoutsetinfo\n"
             "\nReturns statistics about the unspent transaction output set.\n"
             "Note this call may take some time.\n"
             "\nResult:\n"
             "{\n"
             "  \"height\":n,     (numeric) The current block height (index)\n"
             "  \"bestblock\": \"hex\",   (string) the best block hash hex\n"
             "  \"transactions\": n,      (numeric) The number of transactions\n"
             "  \"txouts\": n,            (numeric) The number of output "
             "transactions\n"
             "  \"bogosize\": n,          (numeric) A database-independent "
             "metric for UTXO set size\n"
             "  \"hash_serialized\": \"hash\",   (string) The serialized hash\n"
             "  \"disk_size\": n,         (numeric) The estimated size of the "
             "chainstate on disk\n"
             "  \"total_amount\": x.xxx          (numeric) The total amount\n"
             "}\n"
             "\nExamples:\n" +
             HelpExampleCli("gettxoutsetinfo", "") +
             HelpExampleRpc("gettxoutsetinfo", ""));
     }
 
     UniValue ret(UniValue::VOBJ);
 
     CCoinsStats stats;
     FlushStateToDisk();
     if (GetUTXOStats(pcoinsdbview.get(), stats)) {
         ret.pushKV("height", int64_t(stats.nHeight));
         ret.pushKV("bestblock", stats.hashBlock.GetHex());
         ret.pushKV("transactions", int64_t(stats.nTransactions));
         ret.pushKV("txouts", int64_t(stats.nTransactionOutputs));
         ret.pushKV("bogosize", int64_t(stats.nBogoSize));
         ret.pushKV("hash_serialized", stats.hashSerialized.GetHex());
         ret.pushKV("disk_size", stats.nDiskSize);
         ret.pushKV("total_amount", ValueFromAmount(stats.nTotalAmount));
     } else {
         throw JSONRPCError(RPC_INTERNAL_ERROR, "Unable to read UTXO set");
     }
     return ret;
 }
 
 UniValue gettxout(const Config &config, const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() < 2 ||
         request.params.size() > 3) {
         throw std::runtime_error(
             "gettxout \"txid\" n ( include_mempool )\n"
             "\nReturns details about an unspent transaction output.\n"
             "\nArguments:\n"
             "1. \"txid\"             (string, required) The transaction id\n"
             "2. \"n\"                (numeric, required) vout number\n"
             "3. \"include_mempool\"  (boolean, optional) Whether to include "
             "the mempool. Default: true."
             "     Note that an unspent output that is spent in the mempool "
             "won't appear.\n"
             "\nResult:\n"
             "{\n"
             "  \"bestblock\" : \"hash\",    (string) the block hash\n"
             "  \"confirmations\" : n,       (numeric) The number of "
             "confirmations\n"
             "  \"value\" : x.xxx,           (numeric) The transaction value "
             "in " +
             CURRENCY_UNIT +
             "\n"
             "  \"scriptPubKey\" : {         (json object)\n"
             "     \"asm\" : \"code\",       (string) \n"
             "     \"hex\" : \"hex\",        (string) \n"
             "     \"reqSigs\" : n,          (numeric) Number of required "
             "signatures\n"
             "     \"type\" : \"pubkeyhash\", (string) The type, eg pubkeyhash\n"
             "     \"addresses\" : [          (array of string) array of "
             "bitcoin addresses\n"
             "        \"address\"     (string) bitcoin address\n"
             "        ,...\n"
             "     ]\n"
             "  },\n"
             "  \"coinbase\" : true|false   (boolean) Coinbase or not\n"
             "}\n"
 
             "\nExamples:\n"
             "\nGet unspent transactions\n" +
             HelpExampleCli("listunspent", "") + "\nView the details\n" +
             HelpExampleCli("gettxout", "\"txid\" 1") +
             "\nAs a json rpc call\n" +
             HelpExampleRpc("gettxout", "\"txid\", 1"));
     }
 
     LOCK(cs_main);
 
     UniValue ret(UniValue::VOBJ);
 
     std::string strTxId = request.params[0].get_str();
     TxId txid(uint256S(strTxId));
     int n = request.params[1].get_int();
     COutPoint out(txid, n);
     bool fMempool = true;
     if (!request.params[2].isNull()) {
         fMempool = request.params[2].get_bool();
     }
 
     Coin coin;
     if (fMempool) {
         LOCK(g_mempool.cs);
         CCoinsViewMemPool view(pcoinsTip.get(), g_mempool);
         if (!view.GetCoin(out, coin) || g_mempool.isSpent(out)) {
             return NullUniValue;
         }
     } else {
         if (!pcoinsTip->GetCoin(out, coin)) {
             return NullUniValue;
         }
     }
 
     const CBlockIndex *pindex = LookupBlockIndex(pcoinsTip->GetBestBlock());
     ret.pushKV("bestblock", pindex->GetBlockHash().GetHex());
     if (coin.GetHeight() == MEMPOOL_HEIGHT) {
         ret.pushKV("confirmations", 0);
     } else {
         ret.pushKV("confirmations",
                    int64_t(pindex->nHeight - coin.GetHeight() + 1));
     }
     ret.pushKV("value", ValueFromAmount(coin.GetTxOut().nValue));
     UniValue o(UniValue::VOBJ);
     ScriptPubKeyToUniv(coin.GetTxOut().scriptPubKey, o, true);
     ret.pushKV("scriptPubKey", o);
     ret.pushKV("coinbase", coin.IsCoinBase());
 
     return ret;
 }
 
 static UniValue verifychain(const Config &config,
                             const JSONRPCRequest &request) {
     int nCheckLevel = gArgs.GetArg("-checklevel", DEFAULT_CHECKLEVEL);
     int nCheckDepth = gArgs.GetArg("-checkblocks", DEFAULT_CHECKBLOCKS);
     if (request.fHelp || request.params.size() > 2) {
         throw std::runtime_error(
             "verifychain ( checklevel nblocks )\n"
             "\nVerifies blockchain database.\n"
             "\nArguments:\n"
             "1. checklevel   (numeric, optional, 0-4, default=" +
             strprintf("%d", nCheckLevel) +
             ") How thorough the block verification is.\n"
             "2. nblocks      (numeric, optional, default=" +
             strprintf("%d", nCheckDepth) +
             ", 0=all) The number of blocks to check.\n"
             "\nResult:\n"
             "true|false       (boolean) Verified or not\n"
             "\nExamples:\n" +
             HelpExampleCli("verifychain", "") +
             HelpExampleRpc("verifychain", ""));
     }
 
     LOCK(cs_main);
 
     if (!request.params[0].isNull()) {
         nCheckLevel = request.params[0].get_int();
     }
     if (!request.params[1].isNull()) {
         nCheckDepth = request.params[1].get_int();
     }
 
     return CVerifyDB().VerifyDB(config, pcoinsTip.get(), nCheckLevel,
                                 nCheckDepth);
 }
 
 UniValue getblockchaininfo(const Config &config,
                            const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 0) {
         throw std::runtime_error(
             "getblockchaininfo\n"
             "Returns an object containing various state info regarding "
             "blockchain processing.\n"
             "\nResult:\n"
             "{\n"
             "  \"chain\": \"xxxx\",              (string) current network name "
             "as defined in BIP70 (main, test, regtest)\n"
             "  \"blocks\": xxxxxx,             (numeric) the current number of "
             "blocks processed in the server\n"
             "  \"headers\": xxxxxx,            (numeric) the current number of "
             "headers we have validated\n"
             "  \"bestblockhash\": \"...\",       (string) the hash of the "
             "currently best block\n"
             "  \"difficulty\": xxxxxx,         (numeric) the current "
             "difficulty\n"
             "  \"mediantime\": xxxxxx,         (numeric) median time for the "
             "current best block\n"
             "  \"verificationprogress\": xxxx, (numeric) estimate of "
             "verification progress [0..1]\n"
             "  \"initialblockdownload\": xxxx, (bool) (debug information) "
             "estimate of whether this node is in Initial Block Download mode.\n"
             "  \"chainwork\": \"xxxx\"           (string) total amount of work "
             "in active chain, in hexadecimal\n"
             "  \"size_on_disk\": xxxxxx,       (numeric) the estimated size of "
             "the block and undo files on disk\n"
             "  \"pruned\": xx,                 (boolean) if the blocks are "
             "subject to pruning\n"
             "  \"pruneheight\": xxxxxx,        (numeric) lowest-height "
             "complete block stored (only present if pruning is enabled)\n"
             "  \"automatic_pruning\": xx,      (boolean) whether automatic "
             "pruning is enabled (only present if pruning is enabled)\n"
             "  \"prune_target_size\": xxxxxx,  (numeric) the target size "
             "used by pruning (only present if automatic pruning is enabled)\n"
             "  \"warnings\" : \"...\",           (string) any network and "
             "blockchain warnings.\n"
             "}\n"
             "\nExamples:\n" +
             HelpExampleCli("getblockchaininfo", "") +
             HelpExampleRpc("getblockchaininfo", ""));
     }
 
     LOCK(cs_main);
 
     const CBlockIndex *tip = chainActive.Tip();
     UniValue obj(UniValue::VOBJ);
     obj.pushKV("chain", config.GetChainParams().NetworkIDString());
     obj.pushKV("blocks", int(chainActive.Height()));
     obj.pushKV("headers", pindexBestHeader ? pindexBestHeader->nHeight : -1);
     obj.pushKV("bestblockhash", tip->GetBlockHash().GetHex());
     obj.pushKV("difficulty", double(GetDifficulty(tip)));
     obj.pushKV("mediantime", int64_t(tip->GetMedianTimePast()));
     obj.pushKV("verificationprogress",
                GuessVerificationProgress(Params().TxData(), tip));
     obj.pushKV("initialblockdownload", IsInitialBlockDownload());
     obj.pushKV("chainwork", tip->nChainWork.GetHex());
     obj.pushKV("size_on_disk", CalculateCurrentUsage());
     obj.pushKV("pruned", fPruneMode);
 
     if (fPruneMode) {
         const CBlockIndex *block = tip;
         assert(block);
         while (block->pprev && (block->pprev->nStatus.hasData())) {
             block = block->pprev;
         }
 
         obj.pushKV("pruneheight", block->nHeight);
 
         // if 0, execution bypasses the whole if block.
         bool automatic_pruning = (gArgs.GetArg("-prune", 0) != 1);
         obj.pushKV("automatic_pruning", automatic_pruning);
         if (automatic_pruning) {
             obj.pushKV("prune_target_size", nPruneTarget);
         }
     }
 
     obj.pushKV("warnings", GetWarnings("statusbar"));
     return obj;
 }
 
 /** Comparison function for sorting the getchaintips heads.  */
 struct CompareBlocksByHeight {
     bool operator()(const CBlockIndex *a, const CBlockIndex *b) const {
         // Make sure that unequal blocks with the same height do not compare
         // equal. Use the pointers themselves to make a distinction.
         if (a->nHeight != b->nHeight) {
             return (a->nHeight > b->nHeight);
         }
 
         return a < b;
     }
 };
 
 static UniValue getchaintips(const Config &config,
                              const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 0) {
         throw std::runtime_error(
             "getchaintips\n"
             "Return information about all known tips in the block tree,"
             " including the main chain as well as orphaned branches.\n"
             "\nResult:\n"
             "[\n"
             "  {\n"
             "    \"height\": xxxx,         (numeric) height of the chain tip\n"
             "    \"hash\": \"xxxx\",         (string) block hash of the tip\n"
             "    \"branchlen\": 0          (numeric) zero for main chain\n"
             "    \"status\": \"active\"      (string) \"active\" for the main "
             "chain\n"
             "  },\n"
             "  {\n"
             "    \"height\": xxxx,\n"
             "    \"hash\": \"xxxx\",\n"
             "    \"branchlen\": 1          (numeric) length of branch "
             "connecting the tip to the main chain\n"
             "    \"status\": \"xxxx\"        (string) status of the chain "
             "(active, valid-fork, valid-headers, headers-only, invalid)\n"
             "  }\n"
             "]\n"
             "Possible values for status:\n"
             "1.  \"invalid\"               This branch contains at least one "
             "invalid block\n"
             "2.  \"parked\"                This branch contains at least one "
             "parked block\n"
             "3.  \"headers-only\"          Not all blocks for this branch are "
             "available, but the headers are valid\n"
             "4.  \"valid-headers\"         All blocks are available for this "
             "branch, but they were never fully validated\n"
             "5.  \"valid-fork\"            This branch is not part of the "
             "active chain, but is fully validated\n"
             "6.  \"active\"                This is the tip of the active main "
             "chain, which is certainly valid\n"
             "\nExamples:\n" +
             HelpExampleCli("getchaintips", "") +
             HelpExampleRpc("getchaintips", ""));
     }
 
     LOCK(cs_main);
 
     /**
      * Idea:  the set of chain tips is chainActive.tip, plus orphan blocks which
      * do not have another orphan building off of them.
      * Algorithm:
      *  - Make one pass through mapBlockIndex, picking out the orphan blocks,
      * and also storing a set of the orphan block's pprev pointers.
      *  - Iterate through the orphan blocks. If the block isn't pointed to by
      * another orphan, it is a chain tip.
      *  - add chainActive.Tip()
      */
     std::set<const CBlockIndex *, CompareBlocksByHeight> setTips;
     std::set<const CBlockIndex *> setOrphans;
     std::set<const CBlockIndex *> setPrevs;
 
     for (const std::pair<const uint256, CBlockIndex *> &item : mapBlockIndex) {
         if (!chainActive.Contains(item.second)) {
             setOrphans.insert(item.second);
             setPrevs.insert(item.second->pprev);
         }
     }
 
     for (std::set<const CBlockIndex *>::iterator it = setOrphans.begin();
          it != setOrphans.end(); ++it) {
         if (setPrevs.erase(*it) == 0) {
             setTips.insert(*it);
         }
     }
 
     // Always report the currently active tip.
     setTips.insert(chainActive.Tip());
 
     /* Construct the output array.  */
     UniValue res(UniValue::VARR);
     for (const CBlockIndex *block : setTips) {
         UniValue obj(UniValue::VOBJ);
         obj.pushKV("height", block->nHeight);
         obj.pushKV("hash", block->phashBlock->GetHex());
 
         const int branchLen =
             block->nHeight - chainActive.FindFork(block)->nHeight;
         obj.pushKV("branchlen", branchLen);
 
         std::string status;
         if (chainActive.Contains(block)) {
             // This block is part of the currently active chain.
             status = "active";
         } else if (block->nStatus.isInvalid()) {
             // This block or one of its ancestors is invalid.
             status = "invalid";
         } else if (block->nStatus.isOnParkedChain()) {
             // This block or one of its ancestors is parked.
             status = "parked";
         } else if (block->nChainTx == 0) {
             // This block cannot be connected because full block data for it or
             // one of its parents is missing.
             status = "headers-only";
         } else if (block->IsValid(BlockValidity::SCRIPTS)) {
             // This block is fully validated, but no longer part of the active
             // chain. It was probably the active block once, but was
             // reorganized.
             status = "valid-fork";
         } else if (block->IsValid(BlockValidity::TREE)) {
             // The headers for this block are valid, but it has not been
             // validated. It was probably never part of the most-work chain.
             status = "valid-headers";
         } else {
             // No clue.
             status = "unknown";
         }
         obj.pushKV("status", status);
 
         res.push_back(obj);
     }
 
     return res;
 }
 
 UniValue MempoolInfoToJSON(const CTxMemPool &pool) {
     UniValue ret(UniValue::VOBJ);
     ret.pushKV("loaded", pool.IsLoaded());
     ret.pushKV("size", (int64_t)pool.size());
     ret.pushKV("bytes", (int64_t)pool.GetTotalTxSize());
     ret.pushKV("usage", (int64_t)pool.DynamicMemoryUsage());
     size_t maxmempool =
         gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000;
     ret.pushKV("maxmempool", (int64_t)maxmempool);
     ret.pushKV(
         "mempoolminfee",
         ValueFromAmount(std::max(pool.GetMinFee(maxmempool), ::minRelayTxFee)
                             .GetFeePerK()));
     ret.pushKV("minrelaytxfee", ValueFromAmount(::minRelayTxFee.GetFeePerK()));
 
     return ret;
 }
 
 static UniValue getmempoolinfo(const Config &config,
                                const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 0) {
         throw std::runtime_error(
             "getmempoolinfo\n"
             "\nReturns details on the active state of the TX memory pool.\n"
             "\nResult:\n"
             "{\n"
             "  \"loaded\": true|false         (boolean) True if the mempool is "
             "fully loaded\n"
             "  \"size\": xxxxx,               (numeric) Current tx count\n"
             "  \"bytes\": xxxxx,              (numeric) Transaction size.\n"
             "  \"usage\": xxxxx,              (numeric) Total memory usage for "
             "the mempool\n"
             "  \"maxmempool\": xxxxx,         (numeric) Maximum memory usage "
             "for the mempool\n"
             "  \"mempoolminfee\": xxxxx       (numeric) Minimum fee rate in " +
             CURRENCY_UNIT +
             "/kB for tx to be accepted. Is the maximum of minrelaytxfee and "
             "minimum mempool fee\n"
             "  \"minrelaytxfee\": xxxxx       (numeric) Current minimum relay "
             "fee for transactions\n"
             "}\n"
             "\nExamples:\n" +
             HelpExampleCli("getmempoolinfo", "") +
             HelpExampleRpc("getmempoolinfo", ""));
     }
 
     return MempoolInfoToJSON(::g_mempool);
 }
 
 static UniValue preciousblock(const Config &config,
                               const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 1) {
         throw std::runtime_error(
             "preciousblock \"blockhash\"\n"
             "\nTreats a block as if it were received before others with the "
             "same work.\n"
             "\nA later preciousblock call can override the effect of an "
             "earlier one.\n"
             "\nThe effects of preciousblock are not retained across restarts.\n"
             "\nArguments:\n"
             "1. \"blockhash\"   (string, required) the hash of the block to "
             "mark as precious\n"
             "\nResult:\n"
             "\nExamples:\n" +
             HelpExampleCli("preciousblock", "\"blockhash\"") +
             HelpExampleRpc("preciousblock", "\"blockhash\""));
     }
 
     std::string strHash = request.params[0].get_str();
     uint256 hash(uint256S(strHash));
     CBlockIndex *pblockindex;
 
     {
         LOCK(cs_main);
         pblockindex = LookupBlockIndex(hash);
         if (!pblockindex) {
             throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found");
         }
     }
 
     CValidationState state;
     PreciousBlock(config, state, pblockindex);
 
     if (!state.IsValid()) {
         throw JSONRPCError(RPC_DATABASE_ERROR, state.GetRejectReason());
     }
 
     return NullUniValue;
 }
 
 UniValue finalizeblock(const Config &config, const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 1) {
         throw std::runtime_error(
             "finalizeblock \"blockhash\"\n"
 
             "\nTreats a block as final. It cannot be reorged. Any chain\n"
             "that does not contain this block is invalid. Used on a less\n"
             "work chain, it can effectively PUTS YOU OUT OF CONSENSUS.\n"
             "USE WITH CAUTION!\n"
             "\nResult:\n"
             "\nExamples:\n" +
             HelpExampleCli("finalizeblock", "\"blockhash\"") +
             HelpExampleRpc("finalizeblock", "\"blockhash\""));
     }
 
     std::string strHash = request.params[0].get_str();
     uint256 hash(uint256S(strHash));
     CValidationState state;
 
     {
         LOCK(cs_main);
         CBlockIndex *pblockindex = LookupBlockIndex(hash);
         if (!pblockindex) {
             throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found");
         }
 
         FinalizeBlockAndInvalidate(config, state, pblockindex);
     }
 
     if (state.IsValid()) {
         ActivateBestChain(config, state);
     }
 
     if (!state.IsValid()) {
         throw JSONRPCError(RPC_DATABASE_ERROR, FormatStateMessage(state));
     }
 
     return NullUniValue;
 }
 
 static UniValue invalidateblock(const Config &config,
                                 const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 1) {
         throw std::runtime_error(
             "invalidateblock \"blockhash\"\n"
             "\nPermanently marks a block as invalid, as if it "
             "violated a consensus rule.\n"
             "\nArguments:\n"
             "1. \"blockhash\"   (string, required) the hash of "
             "the block to mark as invalid\n"
             "\nResult:\n"
             "\nExamples:\n" +
             HelpExampleCli("invalidateblock", "\"blockhash\"") +
             HelpExampleRpc("invalidateblock", "\"blockhash\""));
     }
 
     const std::string strHash = request.params[0].get_str();
     const uint256 hash(uint256S(strHash));
     CValidationState state;
 
     {
         LOCK(cs_main);
         CBlockIndex *pblockindex = LookupBlockIndex(hash);
         if (!pblockindex) {
             throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found");
         }
 
         InvalidateBlock(config, state, pblockindex);
     }
 
     if (state.IsValid()) {
         ActivateBestChain(config, state);
     }
 
     if (!state.IsValid()) {
         throw JSONRPCError(RPC_DATABASE_ERROR, FormatStateMessage(state));
     }
 
     return NullUniValue;
 }
 
 UniValue parkblock(const Config &config, const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 1) {
         throw std::runtime_error("parkblock \"blockhash\"\n"
                                  "\nMarks a block as parked.\n"
                                  "\nArguments:\n"
                                  "1. \"blockhash\"   (string, required) the "
                                  "hash of the block to park\n"
                                  "\nResult:\n"
                                  "\nExamples:\n" +
                                  HelpExampleCli("parkblock", "\"blockhash\"") +
                                  HelpExampleRpc("parkblock", "\"blockhash\""));
     }
 
     const std::string strHash = request.params[0].get_str();
     const uint256 hash(uint256S(strHash));
     CValidationState state;
 
     {
         LOCK(cs_main);
         if (mapBlockIndex.count(hash) == 0) {
             throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found");
         }
 
         CBlockIndex *pblockindex = mapBlockIndex[hash];
         ParkBlock(config, state, pblockindex);
     }
 
     if (state.IsValid()) {
         ActivateBestChain(config, state);
     }
 
     if (!state.IsValid()) {
         throw JSONRPCError(RPC_DATABASE_ERROR, state.GetRejectReason());
     }
 
     return NullUniValue;
 }
 
 static UniValue reconsiderblock(const Config &config,
                                 const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 1) {
         throw std::runtime_error(
             "reconsiderblock \"blockhash\"\n"
             "\nRemoves invalidity status of a block and its descendants, "
             "reconsider them for activation.\n"
             "This can be used to undo the effects of invalidateblock.\n"
             "\nArguments:\n"
             "1. \"blockhash\"   (string, required) the hash of the block to "
             "reconsider\n"
             "\nResult:\n"
             "\nExamples:\n" +
             HelpExampleCli("reconsiderblock", "\"blockhash\"") +
             HelpExampleRpc("reconsiderblock", "\"blockhash\""));
     }
 
     const std::string strHash = request.params[0].get_str();
     const uint256 hash(uint256S(strHash));
 
     {
         LOCK(cs_main);
         CBlockIndex *pblockindex = LookupBlockIndex(hash);
         if (!pblockindex) {
             throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found");
         }
 
         ResetBlockFailureFlags(pblockindex);
     }
 
     CValidationState state;
     ActivateBestChain(config, state);
 
     if (!state.IsValid()) {
         throw JSONRPCError(RPC_DATABASE_ERROR, FormatStateMessage(state));
     }
 
     return NullUniValue;
 }
 
 UniValue unparkblock(const Config &config, const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 1) {
         throw std::runtime_error(
             "unparkblock \"blockhash\"\n"
             "\nRemoves parked status of a block and its descendants, "
             "reconsider them for activation.\n"
             "This can be used to undo the effects of parkblock.\n"
             "\nArguments:\n"
             "1. \"blockhash\"   (string, required) the hash of the block to "
             "unpark\n"
             "\nResult:\n"
             "\nExamples:\n" +
             HelpExampleCli("unparkblock", "\"blockhash\"") +
             HelpExampleRpc("unparkblock", "\"blockhash\""));
     }
 
     const std::string strHash = request.params[0].get_str();
     const uint256 hash(uint256S(strHash));
 
     {
         LOCK(cs_main);
         if (mapBlockIndex.count(hash) == 0) {
             throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found");
         }
 
         CBlockIndex *pblockindex = mapBlockIndex[hash];
         UnparkBlockAndChildren(pblockindex);
     }
 
     CValidationState state;
     ActivateBestChain(config, state);
 
     if (!state.IsValid()) {
         throw JSONRPCError(RPC_DATABASE_ERROR, state.GetRejectReason());
     }
 
     return NullUniValue;
 }
 
 static UniValue getchaintxstats(const Config &config,
                                 const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() > 2) {
         throw std::runtime_error(
             "getchaintxstats ( nblocks blockhash )\n"
             "\nCompute statistics about the total number and rate of "
             "transactions in the chain.\n"
             "\nArguments:\n"
             "1. nblocks      (numeric, optional) Size of the window in number "
             "of blocks (default: one month).\n"
             "2. \"blockhash\"  (string, optional) The hash of the block that "
             "ends the window.\n"
             "\nResult:\n"
             "{\n"
             "  \"time\": xxxxx,                         (numeric) The "
             "timestamp for the final block in the window in UNIX format.\n"
             "  \"txcount\": xxxxx,                      (numeric) The total "
             "number of transactions in the chain up to that point.\n"
             "  \"window_final_block_hash\": \"...\",      (string) The hash of "
             "the final block in the window.\n"
             "  \"window_block_count\": xxxxx,           (numeric) Size of "
             "the window in number of blocks.\n"
             "  \"window_tx_count\": xxxxx,              (numeric) The number "
             "of transactions in the window. Only returned if "
             "\"window_block_count\" is > 0.\n"
             "  \"window_interval\": xxxxx,              (numeric) The elapsed "
             "time in the window in seconds. Only returned if "
             "\"window_block_count\" is > 0.\n"
             "  \"txrate\": x.xx,                        (numeric) The average "
             "rate of transactions per second in the window. Only returned if "
             "\"window_interval\" is > 0.\n"
             "}\n"
             "\nExamples:\n" +
             HelpExampleCli("getchaintxstats", "") +
             HelpExampleRpc("getchaintxstats", "2016"));
     }
 
     const CBlockIndex *pindex;
 
     // By default: 1 month
     int blockcount = 30 * 24 * 60 * 60 /
                      config.GetChainParams().GetConsensus().nPowTargetSpacing;
 
     if (request.params[1].isNull()) {
         LOCK(cs_main);
         pindex = chainActive.Tip();
     } else {
         uint256 hash = uint256S(request.params[1].get_str());
         LOCK(cs_main);
         pindex = LookupBlockIndex(hash);
         if (!pindex) {
             throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found");
         }
         if (!chainActive.Contains(pindex)) {
             throw JSONRPCError(RPC_INVALID_PARAMETER,
                                "Block is not in main chain");
         }
     }
 
     assert(pindex != nullptr);
 
     if (request.params[0].isNull()) {
         blockcount = std::max(0, std::min(blockcount, pindex->nHeight - 1));
     } else {
         blockcount = request.params[0].get_int();
 
         if (blockcount < 0 ||
             (blockcount > 0 && blockcount >= pindex->nHeight)) {
             throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid block count: "
                                                       "should be between 0 and "
                                                       "the block's height - 1");
         }
     }
 
     const CBlockIndex *pindexPast =
         pindex->GetAncestor(pindex->nHeight - blockcount);
     int nTimeDiff =
         pindex->GetMedianTimePast() - pindexPast->GetMedianTimePast();
     int nTxDiff = pindex->nChainTx - pindexPast->nChainTx;
 
     UniValue ret(UniValue::VOBJ);
     ret.pushKV("time", int64_t(pindex->nTime));
     ret.pushKV("txcount", int64_t(pindex->nChainTx));
     ret.pushKV("window_final_block_hash", pindex->GetBlockHash().GetHex());
     ret.pushKV("window_block_count", blockcount);
     if (blockcount > 0) {
         ret.pushKV("window_tx_count", nTxDiff);
         ret.pushKV("window_interval", nTimeDiff);
         if (nTimeDiff > 0) {
             ret.pushKV("txrate", double(nTxDiff) / nTimeDiff);
         }
     }
 
     return ret;
 }
 
 template <typename T>
 static T CalculateTruncatedMedian(std::vector<T> &scores) {
     size_t size = scores.size();
     if (size == 0) {
         return T();
     }
 
     std::sort(scores.begin(), scores.end());
     if (size % 2 == 0) {
         return (scores[size / 2 - 1] + scores[size / 2]) / 2;
     } else {
         return scores[size / 2];
     }
 }
 
 template <typename T> static inline bool SetHasKeys(const std::set<T> &set) {
     return false;
 }
 template <typename T, typename Tk, typename... Args>
 static inline bool SetHasKeys(const std::set<T> &set, const Tk &key,
                               const Args &... args) {
     return (set.count(key) != 0) || SetHasKeys(set, args...);
 }
 
 // outpoint (needed for the utxo index) + nHeight + fCoinBase
 static constexpr size_t PER_UTXO_OVERHEAD =
     sizeof(COutPoint) + sizeof(uint32_t) + sizeof(bool);
 
 static UniValue getblockstats(const Config &config,
                               const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() < 1 ||
         request.params.size() > 4) {
         throw std::runtime_error(
             "getblockstats hash_or_height ( stats )\n"
             "\nCompute per block statistics for a given window. All amounts "
             "are in " +
             CURRENCY_UNIT +
             ".\n"
             "It won't work for some heights with pruning.\n"
             "It won't work without -txindex for utxo_size_inc, *fee or "
             "*feerate stats.\n"
             "\nArguments:\n"
             "1. \"hash_or_height\"     (string or numeric, required) The block "
             "hash or height of the target block\n"
             "2. \"stats\"              (array,  optional) Values to plot, by "
             "default all values (see result below)\n"
             "    [\n"
             "      \"height\",         (string, optional) Selected statistic\n"
             "      \"time\",           (string, optional) Selected statistic\n"
             "      ,...\n"
             "    ]\n"
             "\nResult:\n"
             "{                           (json object)\n"
             "  \"avgfee\": x.xxx,          (numeric) Average fee in the block\n"
             "  \"avgfeerate\": x.xxx,      (numeric) Average feerate (in " +
             CURRENCY_UNIT +
             " per byte)\n"
             "  \"avgtxsize\": xxxxx,       (numeric) Average transaction size\n"
             "  \"blockhash\": xxxxx,       (string) The block hash (to check "
             "for potential reorgs)\n"
             "  \"height\": xxxxx,          (numeric) The height of the block\n"
             "  \"ins\": xxxxx,             (numeric) The number of inputs "
             "(excluding coinbase)\n"
             "  \"maxfee\": xxxxx,          (numeric) Maximum fee in the block\n"
             "  \"maxfeerate\": xxxxx,      (numeric) Maximum feerate (in " +
             CURRENCY_UNIT +
             " per byte)\n"
             "  \"maxtxsize\": xxxxx,       (numeric) Maximum transaction size\n"
             "  \"medianfee\": x.xxx,       (numeric) Truncated median fee in "
             "the block\n"
             "  \"medianfeerate\": x.xxx,   (numeric) Truncated median feerate "
             "(in " +
             CURRENCY_UNIT +
             " per byte)\n"
             "  \"mediantime\": xxxxx,      (numeric) The block median time "
             "past\n"
             "  \"mediantxsize\": xxxxx,    (numeric) Truncated median "
             "transaction size\n"
             "  \"minfee\": x.xxx,          (numeric) Minimum fee in the block\n"
             "  \"minfeerate\": xx.xx,      (numeric) Minimum feerate (in " +
             CURRENCY_UNIT +
             " per byte)\n"
             "  \"mintxsize\": xxxxx,       (numeric) Minimum transaction size\n"
             "  \"outs\": xxxxx,            (numeric) The number of outputs\n"
             "  \"subsidy\": x.xxx,         (numeric) The block subsidy\n"
             "  \"time\": xxxxx,            (numeric) The block time\n"
             "  \"total_out\": x.xxx,       (numeric) Total amount in all "
             "outputs (excluding coinbase and thus reward [ie subsidy + "
             "totalfee])\n"
             "  \"total_size\": xxxxx,      (numeric) Total size of all "
             "non-coinbase transactions\n"
             "  \"totalfee\": x.xxx,        (numeric) The fee total\n"
             "  \"txs\": xxxxx,             (numeric) The number of "
             "transactions (excluding coinbase)\n"
             "  \"utxo_increase\": xxxxx,   (numeric) The increase/decrease in "
             "the number of unspent outputs\n"
             "  \"utxo_size_inc\": xxxxx,   (numeric) The increase/decrease in "
             "size for the utxo index (not discounting op_return and similar)\n"
             "}\n"
             "\nExamples:\n" +
             HelpExampleCli("getblockstats",
                            "1000 '[\"minfeerate\",\"avgfeerate\"]'") +
             HelpExampleRpc("getblockstats",
                            "1000 '[\"minfeerate\",\"avgfeerate\"]'"));
     }
 
     LOCK(cs_main);
 
     CBlockIndex *pindex;
     if (request.params[0].isNum()) {
         const int height = request.params[0].get_int();
         const int current_tip = chainActive.Height();
         if (height < 0) {
             throw JSONRPCError(
                 RPC_INVALID_PARAMETER,
                 strprintf("Target block height %d is negative", height));
         }
         if (height > current_tip) {
             throw JSONRPCError(
                 RPC_INVALID_PARAMETER,
                 strprintf("Target block height %d after current tip %d", height,
                           current_tip));
         }
 
         pindex = chainActive[height];
     } else {
         const std::string strHash = request.params[0].get_str();
         const uint256 hash(uint256S(strHash));
         pindex = LookupBlockIndex(hash);
         if (!pindex) {
             throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found");
         }
         if (!chainActive.Contains(pindex)) {
             throw JSONRPCError(RPC_INVALID_PARAMETER,
                                strprintf("Block is not in chain %s",
                                          Params().NetworkIDString()));
         }
     }
 
     assert(pindex != nullptr);
 
     std::set<std::string> stats;
     if (!request.params[1].isNull()) {
         const UniValue stats_univalue = request.params[1].get_array();
         for (unsigned int i = 0; i < stats_univalue.size(); i++) {
             const std::string stat = stats_univalue[i].get_str();
             stats.insert(stat);
         }
     }
 
     const CBlock block = GetBlockChecked(config, pindex);
 
     // Calculate everything if nothing selected (default)
     const bool do_all = stats.size() == 0;
     const bool do_mediantxsize = do_all || stats.count("mediantxsize") != 0;
     const bool do_medianfee = do_all || stats.count("medianfee") != 0;
     const bool do_medianfeerate = do_all || stats.count("medianfeerate") != 0;
     const bool loop_inputs =
         do_all || do_medianfee || do_medianfeerate ||
         SetHasKeys(stats, "utxo_size_inc", "totalfee", "avgfee", "avgfeerate",
                    "minfee", "maxfee", "minfeerate", "maxfeerate");
     const bool loop_outputs = do_all || loop_inputs || stats.count("total_out");
     const bool do_calculate_size =
         do_mediantxsize || loop_inputs ||
         SetHasKeys(stats, "total_size", "avgtxsize", "mintxsize", "maxtxsize");
 
     const int64_t blockMaxSize = config.GetMaxBlockSize();
     Amount maxfee = Amount::zero();
     Amount maxfeerate = Amount::zero();
     Amount minfee = MAX_MONEY;
     Amount minfeerate = MAX_MONEY;
     Amount total_out = Amount::zero();
     Amount totalfee = Amount::zero();
     int64_t inputs = 0;
     int64_t maxtxsize = 0;
     int64_t mintxsize = blockMaxSize;
     int64_t outputs = 0;
     int64_t total_size = 0;
     int64_t utxo_size_inc = 0;
     std::vector<Amount> fee_array;
     std::vector<Amount> feerate_array;
     std::vector<int64_t> txsize_array;
 
     const Consensus::Params &params = config.GetChainParams().GetConsensus();
 
     for (const auto &tx : block.vtx) {
         outputs += tx->vout.size();
         Amount tx_total_out = Amount::zero();
         if (loop_outputs) {
             for (const CTxOut &out : tx->vout) {
                 tx_total_out += out.nValue;
                 utxo_size_inc +=
                     GetSerializeSize(out, SER_NETWORK, PROTOCOL_VERSION) +
                     PER_UTXO_OVERHEAD;
             }
         }
 
         if (tx->IsCoinBase()) {
             continue;
         }
 
         // Don't count coinbase's fake input
         inputs += tx->vin.size();
         // Don't count coinbase reward
         total_out += tx_total_out;
 
         int64_t tx_size = 0;
         if (do_calculate_size) {
 
             tx_size = tx->GetTotalSize();
             if (do_mediantxsize) {
                 txsize_array.push_back(tx_size);
             }
             maxtxsize = std::max(maxtxsize, tx_size);
             mintxsize = std::min(mintxsize, tx_size);
             total_size += tx_size;
         }
 
         if (loop_inputs) {
             if (!g_txindex) {
                 throw JSONRPCError(RPC_INVALID_PARAMETER,
                                    "One or more of the selected stats requires "
                                    "-txindex enabled");
             }
 
             Amount tx_total_in = Amount::zero();
             for (const CTxIn &in : tx->vin) {
                 CTransactionRef tx_in;
                 uint256 hashBlock;
                 if (!GetTransaction(params, in.prevout.GetTxId(), tx_in,
                                     hashBlock, false)) {
                     throw JSONRPCError(RPC_INTERNAL_ERROR,
                                        std::string("Unexpected internal error "
                                                    "(tx index seems corrupt)"));
                 }
 
                 CTxOut prevoutput = tx_in->vout[in.prevout.GetN()];
 
                 tx_total_in += prevoutput.nValue;
                 utxo_size_inc -= GetSerializeSize(prevoutput, SER_NETWORK,
                                                   PROTOCOL_VERSION) +
                                  PER_UTXO_OVERHEAD;
             }
 
             Amount txfee = tx_total_in - tx_total_out;
             assert(MoneyRange(txfee));
             if (do_medianfee) {
                 fee_array.push_back(txfee);
             }
             maxfee = std::max(maxfee, txfee);
             minfee = std::min(minfee, txfee);
             totalfee += txfee;
 
             Amount feerate = txfee / tx_size;
             if (do_medianfeerate) {
                 feerate_array.push_back(feerate);
             }
             maxfeerate = std::max(maxfeerate, feerate);
             minfeerate = std::min(minfeerate, feerate);
         }
     }
 
     UniValue ret_all(UniValue::VOBJ);
     ret_all.pushKV("avgfee",
                    ValueFromAmount((block.vtx.size() > 1)
                                        ? totalfee / int((block.vtx.size() - 1))
                                        : Amount::zero()));
     ret_all.pushKV("avgfeerate",
                    ValueFromAmount((total_size > 0) ? totalfee / total_size
                                                     : Amount::zero()));
     ret_all.pushKV("avgtxsize", (block.vtx.size() > 1)
                                     ? total_size / (block.vtx.size() - 1)
                                     : 0);
     ret_all.pushKV("blockhash", pindex->GetBlockHash().GetHex());
     ret_all.pushKV("height", (int64_t)pindex->nHeight);
     ret_all.pushKV("ins", inputs);
     ret_all.pushKV("maxfee", ValueFromAmount(maxfee));
     ret_all.pushKV("maxfeerate", ValueFromAmount(maxfeerate));
     ret_all.pushKV("maxtxsize", maxtxsize);
     ret_all.pushKV("medianfee",
                    ValueFromAmount(CalculateTruncatedMedian(fee_array)));
     ret_all.pushKV("medianfeerate",
                    ValueFromAmount(CalculateTruncatedMedian(feerate_array)));
     ret_all.pushKV("mediantime", pindex->GetMedianTimePast());
     ret_all.pushKV("mediantxsize", CalculateTruncatedMedian(txsize_array));
     ret_all.pushKV(
         "minfee",
         ValueFromAmount((minfee == MAX_MONEY) ? Amount::zero() : minfee));
     ret_all.pushKV("minfeerate",
                    ValueFromAmount((minfeerate == MAX_MONEY) ? Amount::zero()
                                                              : minfeerate));
     ret_all.pushKV("mintxsize", mintxsize == blockMaxSize ? 0 : mintxsize);
     ret_all.pushKV("outs", outputs);
     ret_all.pushKV("subsidy", ValueFromAmount(GetBlockSubsidy(
                                   pindex->nHeight, Params().GetConsensus())));
     ret_all.pushKV("time", pindex->GetBlockTime());
     ret_all.pushKV("total_out", ValueFromAmount(total_out));
     ret_all.pushKV("total_size", total_size);
     ret_all.pushKV("totalfee", ValueFromAmount(totalfee));
     ret_all.pushKV("txs", (int64_t)block.vtx.size());
     ret_all.pushKV("utxo_increase", outputs - inputs);
     ret_all.pushKV("utxo_size_inc", utxo_size_inc);
 
     if (do_all) {
         return ret_all;
     }
 
     UniValue ret(UniValue::VOBJ);
     for (const std::string &stat : stats) {
         const UniValue &value = ret_all[stat];
         if (value.isNull()) {
             throw JSONRPCError(
                 RPC_INVALID_PARAMETER,
                 strprintf("Invalid selected statistic %s", stat));
         }
         ret.pushKV(stat, value);
     }
     return ret;
 }
 
 static UniValue savemempool(const Config &config,
                             const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() != 0) {
         throw std::runtime_error("savemempool\n"
                                  "\nDumps the mempool to disk. It will fail "
                                  "until the previous dump is fully loaded.\n"
                                  "\nExamples:\n" +
                                  HelpExampleCli("savemempool", "") +
                                  HelpExampleRpc("savemempool", ""));
     }
 
     if (!::g_mempool.IsLoaded()) {
         throw JSONRPCError(RPC_MISC_ERROR, "The mempool was not loaded yet");
     }
 
     if (!DumpMempool(::g_mempool)) {
         throw JSONRPCError(RPC_MISC_ERROR, "Unable to dump mempool to disk");
     }
 
     return NullUniValue;
 }
 
 //! Search for a given set of pubkey scripts
 static bool FindScriptPubKey(std::atomic<int> &scan_progress,
                              const std::atomic<bool> &should_abort,
                              int64_t &count, CCoinsViewCursor *cursor,
                              const std::set<CScript> &needles,
                              std::map<COutPoint, Coin> &out_results) {
     scan_progress = 0;
     count = 0;
     while (cursor->Valid()) {
         COutPoint key;
         Coin coin;
         if (!cursor->GetKey(key) || !cursor->GetValue(coin)) {
             return false;
         }
         if (++count % 8192 == 0) {
             boost::this_thread::interruption_point();
             if (should_abort) {
                 // allow to abort the scan via the abort reference
                 return false;
             }
         }
         if (count % 256 == 0) {
             // update progress reference every 256 item
             const TxId &txid = key.GetTxId();
             uint32_t high = 0x100 * *txid.begin() + *(txid.begin() + 1);
             scan_progress = int(high * 100.0 / 65536.0 + 0.5);
         }
         if (needles.count(coin.GetTxOut().scriptPubKey)) {
             out_results.emplace(key, coin);
         }
         cursor->Next();
     }
     scan_progress = 100;
     return true;
 }
 
 /** RAII object to prevent concurrency issue when scanning the txout set */
 static std::mutex g_utxosetscan;
 static std::atomic<int> g_scan_progress;
 static std::atomic<bool> g_scan_in_progress;
 static std::atomic<bool> g_should_abort_scan;
 class CoinsViewScanReserver {
 private:
     bool m_could_reserve;
 
 public:
     explicit CoinsViewScanReserver() : m_could_reserve(false) {}
 
     bool reserve() {
         assert(!m_could_reserve);
         std::lock_guard<std::mutex> lock(g_utxosetscan);
         if (g_scan_in_progress) {
             return false;
         }
         g_scan_in_progress = true;
         m_could_reserve = true;
         return true;
     }
 
     ~CoinsViewScanReserver() {
         if (m_could_reserve) {
             std::lock_guard<std::mutex> lock(g_utxosetscan);
             g_scan_in_progress = false;
         }
     }
 };
 
 static UniValue scantxoutset(const Config &config,
                              const JSONRPCRequest &request) {
     if (request.fHelp || request.params.size() < 1 ||
         request.params.size() > 2) {
         throw std::runtime_error(
             "scantxoutset <action> ( <scanobjects> )\n"
             "\nEXPERIMENTAL warning: this call may be removed or changed in "
             "future releases.\n"
             "\nScans the unspent transaction output set for entries that match "
             "certain output descriptors.\n"
             "Examples of output descriptors are:\n"
             "    addr(<address>)                      Outputs whose "
             "scriptPubKey corresponds to the specified address (does not "
             "include P2PK)\n"
             "    raw(<hex script>)                    Outputs whose "
             "scriptPubKey equals the specified hex scripts\n"
             "    combo(<pubkey>)                      P2PK and P2PKH outputs "
             "for the given pubkey\n"
             "    pkh(<pubkey>)                        P2PKH outputs for the "
             "given pubkey\n"
             "    sh(multi(<n>,<pubkey>,<pubkey>,...)) P2SH-multisig outputs "
             "for the given threshold and pubkeys\n"
             "\nIn the above, <pubkey> either refers to a fixed public key in "
             "hexadecimal notation, or to an xpub/xprv optionally followed by "
             "one\n"
             "or more path elements separated by \"/\", and optionally ending "
             "in \"/*\" (unhardened), or \"/*'\" or \"/*h\" (hardened) to "
             "specify all\n"
             "unhardened or hardened child keys.\n"
             "In the latter case, a range needs to be specified by below if "
             "different from 1000.\n"
             "For more information on output descriptors, see the documentation "
-            "at TODO\n"
+            "in the doc/descriptors.md file.\n"
             "\nArguments:\n"
             "1. \"action\"                       (string, required) The action "
             "to execute\n"
             "                                      \"start\" for starting a "
             "scan\n"
             "                                      \"abort\" for aborting the "
             "current scan (returns true when abort was successful)\n"
             "                                      \"status\" for progress "
             "report (in %) of the current scan\n"
             "2. \"scanobjects\"                  (array, required) Array of "
             "scan objects\n"
             "    [                             Every scan object is either a "
             "string descriptor or an object:\n"
             "        \"descriptor\",             (string, optional) An output "
             "descriptor\n"
             "        {                         (object, optional) An object "
             "with output descriptor and metadata\n"
             "          \"desc\": \"descriptor\",   (string, required) An "
             "output descriptor\n"
             "          \"range\": n,             (numeric, optional) Up to "
             "what child index HD chains should be explored (default: 1000)\n"
             "        },\n"
             "        ...\n"
             "    ]\n"
             "\nResult:\n"
             "{\n"
             "  \"unspents\": [\n"
             "    {\n"
             "    \"txid\" : \"transactionid\",     (string) The transaction "
             "id\n"
             "    \"vout\": n,                    (numeric) the vout value\n"
             "    \"scriptPubKey\" : \"script\",    (string) the script key\n"
             "    \"amount\" : x.xxx,             (numeric) The total amount "
             "in " +
             CURRENCY_UNIT +
             " of the unspent output\n"
             "    \"height\" : n,                 (numeric) Height of the "
             "unspent transaction output\n"
             "   }\n"
             "   ,...], \n"
             " \"total_amount\" : x.xxx,          (numeric) The total amount of "
             "all found unspent outputs in " +
             CURRENCY_UNIT +
             "\n"
             "]\n");
     }
 
     RPCTypeCheck(request.params, {UniValue::VSTR, UniValue::VARR});
 
     UniValue result(UniValue::VOBJ);
     if (request.params[0].get_str() == "status") {
         CoinsViewScanReserver reserver;
         if (reserver.reserve()) {
             // no scan in progress
             return NullUniValue;
         }
         result.pushKV("progress", g_scan_progress);
         return result;
     } else if (request.params[0].get_str() == "abort") {
         CoinsViewScanReserver reserver;
         if (reserver.reserve()) {
             // reserve was possible which means no scan was running
             return false;
         }
         // set the abort flag
         g_should_abort_scan = true;
         return true;
     } else if (request.params[0].get_str() == "start") {
         CoinsViewScanReserver reserver;
         if (!reserver.reserve()) {
             throw JSONRPCError(
                 RPC_INVALID_PARAMETER,
                 "Scan already in progress, use action \"abort\" or \"status\"");
         }
         std::set<CScript> needles;
         Amount total_in = Amount::zero();
 
         // loop through the scan objects
         for (const UniValue &scanobject :
              request.params[1].get_array().getValues()) {
             std::string desc_str;
             int range = 1000;
             if (scanobject.isStr()) {
                 desc_str = scanobject.get_str();
             } else if (scanobject.isObject()) {
                 UniValue desc_uni = find_value(scanobject, "desc");
                 if (desc_uni.isNull()) {
                     throw JSONRPCError(
                         RPC_INVALID_PARAMETER,
                         "Descriptor needs to be provided in scan object");
                 }
                 desc_str = desc_uni.get_str();
                 UniValue range_uni = find_value(scanobject, "range");
                 if (!range_uni.isNull()) {
                     range = range_uni.get_int();
                     if (range < 0 || range > 1000000) {
                         throw JSONRPCError(RPC_INVALID_PARAMETER,
                                            "range out of range");
                     }
                 }
             } else {
                 throw JSONRPCError(
                     RPC_INVALID_PARAMETER,
                     "Scan object needs to be either a string or an object");
             }
 
             FlatSigningProvider provider;
             auto desc = Parse(desc_str, provider);
             if (!desc) {
                 throw JSONRPCError(
                     RPC_INVALID_ADDRESS_OR_KEY,
                     strprintf("Invalid descriptor '%s'", desc_str));
             }
             if (!desc->IsRange()) {
                 range = 0;
             }
             for (int i = 0; i <= range; ++i) {
                 std::vector<CScript> scripts;
                 if (!desc->Expand(i, provider, scripts, provider)) {
                     throw JSONRPCError(
                         RPC_INVALID_ADDRESS_OR_KEY,
                         strprintf(
                             "Cannot derive script without private keys: '%s'",
                             desc_str));
                 }
                 needles.insert(scripts.begin(), scripts.end());
             }
         }
 
         // Scan the unspent transaction output set for inputs
         UniValue unspents(UniValue::VARR);
         std::vector<CTxOut> input_txos;
         std::map<COutPoint, Coin> coins;
         g_should_abort_scan = false;
         g_scan_progress = 0;
         int64_t count = 0;
         std::unique_ptr<CCoinsViewCursor> pcursor;
         {
             LOCK(cs_main);
             FlushStateToDisk();
             pcursor = std::unique_ptr<CCoinsViewCursor>(pcoinsdbview->Cursor());
             assert(pcursor);
         }
         bool res = FindScriptPubKey(g_scan_progress, g_should_abort_scan, count,
                                     pcursor.get(), needles, coins);
         result.pushKV("success", res);
         result.pushKV("searched_items", count);
 
         for (const auto &it : coins) {
             const COutPoint &outpoint = it.first;
             const Coin &coin = it.second;
             const CTxOut &txo = coin.GetTxOut();
             input_txos.push_back(txo);
             total_in += txo.nValue;
 
             UniValue unspent(UniValue::VOBJ);
             unspent.pushKV("txid", outpoint.GetTxId().GetHex());
             unspent.pushKV("vout", int32_t(outpoint.GetN()));
             unspent.pushKV("scriptPubKey", HexStr(txo.scriptPubKey.begin(),
                                                   txo.scriptPubKey.end()));
             unspent.pushKV("amount", ValueFromAmount(txo.nValue));
             unspent.pushKV("height", int32_t(coin.GetHeight()));
 
             unspents.push_back(unspent);
         }
         result.pushKV("unspents", unspents);
         result.pushKV("total_amount", ValueFromAmount(total_in));
     } else {
         throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid command");
     }
     return result;
 }
 
 // clang-format off
 static const ContextFreeRPCCommand commands[] = {
     //  category            name                      actor (function)        argNames
     //  ------------------- ------------------------  ----------------------  ----------
     { "blockchain",         "getbestblockhash",       getbestblockhash,       {} },
     { "blockchain",         "getblock",               getblock,               {"blockhash","verbosity|verbose"} },
     { "blockchain",         "getblockchaininfo",      getblockchaininfo,      {} },
     { "blockchain",         "getblockcount",          getblockcount,          {} },
     { "blockchain",         "getblockhash",           getblockhash,           {"height"} },
     { "blockchain",         "getblockheader",         getblockheader,         {"blockhash","verbose"} },
     { "blockchain",         "getblockstats",          getblockstats,          {"hash_or_height","stats"} },
     { "blockchain",         "getchaintips",           getchaintips,           {} },
     { "blockchain",         "getchaintxstats",        getchaintxstats,        {"nblocks", "blockhash"} },
     { "blockchain",         "getdifficulty",          getdifficulty,          {} },
     { "blockchain",         "getmempoolancestors",    getmempoolancestors,    {"txid","verbose"} },
     { "blockchain",         "getmempooldescendants",  getmempooldescendants,  {"txid","verbose"} },
     { "blockchain",         "getmempoolentry",        getmempoolentry,        {"txid"} },
     { "blockchain",         "getmempoolinfo",         getmempoolinfo,         {} },
     { "blockchain",         "getrawmempool",          getrawmempool,          {"verbose"} },
     { "blockchain",         "gettxout",               gettxout,               {"txid","n","include_mempool"} },
     { "blockchain",         "gettxoutsetinfo",        gettxoutsetinfo,        {} },
     { "blockchain",         "pruneblockchain",        pruneblockchain,        {"height"} },
     { "blockchain",         "savemempool",            savemempool,            {} },
     { "blockchain",         "verifychain",            verifychain,            {"checklevel","nblocks"} },
     { "blockchain",         "preciousblock",          preciousblock,          {"blockhash"} },
     { "blockchain",         "scantxoutset",           scantxoutset,           {"action", "scanobjects"} },
 
     /* Not shown in help */
     { "hidden",             "getfinalizedblockhash",            getfinalizedblockhash,            {} },
     { "hidden",             "finalizeblock",                    finalizeblock,                    {"blockhash"} },
     { "hidden",             "invalidateblock",                  invalidateblock,                  {"blockhash"} },
     { "hidden",             "parkblock",                        parkblock,                        {"blockhash"} },
     { "hidden",             "reconsiderblock",                  reconsiderblock,                  {"blockhash"} },
     { "hidden",             "syncwithvalidationinterfacequeue", syncwithvalidationinterfacequeue, {} },
     { "hidden",             "unparkblock",                      unparkblock,                      {"blockhash"} },
     { "hidden",             "waitfornewblock",                  waitfornewblock,                  {"timeout"} },
     { "hidden",             "waitforblock",                     waitforblock,                     {"blockhash","timeout"} },
     { "hidden",             "waitforblockheight",               waitforblockheight,               {"height","timeout"} },
 };
 // clang-format on
 
 void RegisterBlockchainRPCCommands(CRPCTable &t) {
     for (unsigned int vcidx = 0; vcidx < ARRAYLEN(commands); vcidx++) {
         t.appendCommand(commands[vcidx].name, &commands[vcidx]);
     }
 }
diff --git a/src/script/descriptor.h b/src/script/descriptor.h
index 054d668b0..5f6e58c7f 100644
--- a/src/script/descriptor.h
+++ b/src/script/descriptor.h
@@ -1,117 +1,68 @@
 // Copyright (c) 2018 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #ifndef BITCOIN_SCRIPT_DESCRIPTOR_H
 #define BITCOIN_SCRIPT_DESCRIPTOR_H
 
 #include <script/script.h>
 #include <script/sign.h>
 
 #include <vector>
 
 // Descriptors are strings that describe a set of scriptPubKeys, together with
 // all information necessary to solve them. By combining all information into
 // one, they avoid the need to separately import keys and scripts.
 //
 // Descriptors may be ranged, which occurs when the public keys inside are
 // specified in the form of HD chains (xpubs).
 //
 // Descriptors always represent public information - public keys and scripts -
 // but in cases where private keys need to be conveyed along with a descriptor,
 // they can be included inside by changing public keys to private keys (WIF
 // format), and changing xpubs by xprvs.
 //
-// 1. Examples
-//
-// A P2PK descriptor with a fixed public key:
-// - pk(0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798)
-//
-// A P2SH-P2PKH descriptor with a fixed public key:
-// -
-// sh(pkh(02e493dbf1c10d80f3581e4904930b1404cc6c13900ee0758474fa94abe8c4cd13))
-//
-// A bare 1-of-2 multisig descriptor:
-// -
-// multi(1,022f8bde4d1a07209355b4a7250a5c5128e88b84bddc619ab7cba8d569b240efe4,025cbdf0646e5db4eaa398f365f2ea7a0e3d419b7e0330e39ce92bddedcac4f9bc)
-//
-// A chain of P2PKH outputs (this needs the corresponding private key to
-// derive):
-// -
-// pkh(xpub68Gmy5EdvgibQVfPdqkBBCHxA5htiqg55crXYuXoQRKfDBFA1WEjWgP6LHhwBZeNK1VTsfTFUHCdrfp1bgwQ9xv5ski8PX9rL2dZXvgGDnw/1'/2/*)
-//
-// 2. Grammar description:
-//
-// X: xpub or xprv encoded extended key
-// I: decimal encoded integer
-// H: Hex encoded byte array
-// A: Address in P2PKH, or P2SH encoding
-//
-// S (Scripts):
-// * pk(P): Pay-to-pubkey (P2PK) output for public key P.
-// * pkh(P): Pay-to-pubkey-hash (P2PKH) output for public key P.
-// * sh(S): Pay-to-script-hash (P2SH) output for script S
-// * combo(P): combination of P2PK, P2PKH for public key P.
-// * multi(I,L): k-of-n multisig for given public keys
-// * addr(A): Output to address
-// * raw(H): scriptPubKey with raw bytes
-//
-// P (Public keys):
-// * H: fixed public key (or WIF-encoded private key)
-// * E: extended public key
-// * E/*: (ranged) all unhardened direct children of an extended public key
-// * E/*': (ranged) all hardened direct children of an extended public key
-//
-// L (Comma-separated lists of public keys):
-// * P
-// * L,P
-//
-// E (Extended public keys):
-// * X
-// * E/I: unhardened child
-// * E/I': hardened child
-// * E/Ih: hardened child (alternative notation)
-//
-// The top level is S.
+// Reference documentation about the descriptor language can be found in
+// doc/descriptors.md.
 
 /** Interface for parsed descriptor objects. */
 struct Descriptor {
     virtual ~Descriptor() = default;
 
     /** Whether the expansion of this descriptor depends on the position. */
     virtual bool IsRange() const = 0;
 
     /** Convert the descriptor back to a string, undoing parsing. */
     virtual std::string ToString() const = 0;
 
     /**
      * Convert the descriptor to a private string. This fails if the provided
      * provider does not have the relevant private keys.
      */
     virtual bool ToPrivateString(const SigningProvider &provider,
                                  std::string &out) const = 0;
 
     /**
      * Expand a descriptor at a specified position.
      *
      * pos: the position at which to expand the descriptor. If IsRange() is
      *      false, this is ignored.
      * provider: the provider to query for private keys in case of hardened
      *           derivation.
      * output_script: the expanded scriptPubKeys will be put here.
      * out: scripts and public keys necessary for solving the expanded
      *      scriptPubKeys will be put here (may be equal to provider).
      */
     virtual bool Expand(int pos, const SigningProvider &provider,
                         std::vector<CScript> &output_scripts,
                         FlatSigningProvider &out) const = 0;
 };
 
 /**
  * Parse a descriptor string. Included private keys are put in out.
  * Returns nullptr if parsing fails.
  */
 std::unique_ptr<Descriptor> Parse(const std::string &descriptor,
                                   FlatSigningProvider &out);
 
 #endif // BITCOIN_SCRIPT_DESCRIPTOR_H