fix RPC documentation inconsistencies

diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp
index aa80fb6..8f2ebb1 100644
--- a/src/rpc/blockchain.cpp
+++ b/src/rpc/blockchain.cpp
@@ -641,7 +641,6 @@ static RPCHelpMan getblockheader()
                             {RPCResult::Type::NUM_TIME, "mediantime", "The median block time expressed in " + UNIX_EPOCH_TIME},
                             {RPCResult::Type::NUM, "nonce", /*optional=*/true, "The nonce"},
                             {RPCResult::Type::STR_HEX, "bits", /*optional=*/true, "The bits"},
-                            {RPCResult::Type::STR_HEX, "target", /*optional=*/true, "The difficulty target"},
                             {RPCResult::Type::NUM, "difficulty", /*optional=*/true, "The difficulty"},
                             {RPCResult::Type::STR_HEX, "chainwork", /*optional=*/true, "Expected number of hashes required to produce the current chain"},
                             {RPCResult::Type::NUM, "nTx", "The number of transactions in the block"},
@@ -843,7 +842,6 @@ static RPCHelpMan getblock()
                     {RPCResult::Type::NUM_TIME, "mediantime", "The median block time expressed in " + UNIX_EPOCH_TIME},
                     {RPCResult::Type::NUM, "nonce", /*optional=*/true, "The nonce"},
                     {RPCResult::Type::STR_HEX, "bits", /*optional=*/true, "The bits"},
-                    {RPCResult::Type::STR_HEX, "target", /*optional=*/true, "The difficulty target"},
                     {RPCResult::Type::NUM, "difficulty", /*optional=*/true, "The difficulty"},
                     {RPCResult::Type::STR_HEX, "chainwork", /*optional=*/true, "Expected number of hashes required to produce the chain up to this block"},
                     {RPCResult::Type::NUM, "nTx", "The number of transactions in the block"},
@@ -867,7 +865,7 @@ static RPCHelpMan getblock()
                                 {RPCResult::Type::ELISION, "", ""}
                             }},
                         }},
-                        {RPCResult::Type::OBJ, "proposed", "Proposed parameters. Uninforced. Must be published in full",
+                        {RPCResult::Type::OBJ, "proposed", "Proposed parameters. Unenforced. Must be published in full",
                         {
                             {RPCResult::Type::ELISION, "", "same entries as \"current\""}
                         }},
@@ -2477,7 +2475,7 @@ static RPCHelpMan scantxoutset()
                         {RPCResult::Type::STR_HEX, "scriptPubKey", "The output script"},
                         {RPCResult::Type::STR, "desc", "A specialized descriptor for the matched output script"},
                         {RPCResult::Type::STR_AMOUNT, "amount", "The total amount in " + CURRENCY_UNIT + " of the unspent output"},
-                        {RPCResult::Type::STR_HEX, "asset", "The asset ID"},
+                        {RPCResult::Type::STR_HEX, "asset", /*optional=*/true,  "The asset ID"},
                         {RPCResult::Type::BOOL, "coinbase", "Whether this is a coinbase output"},
                         {RPCResult::Type::NUM, "height", "Height of the unspent transaction output"},
                         {RPCResult::Type::STR_HEX, "blockhash", "Blockhash of the unspent transaction output"},
@@ -2900,7 +2898,7 @@ static RPCHelpMan getdescriptoractivity()
                         {RPCResult::Type::STR_HEX, "blockhash", /*optional=*/true, "The blockhash this spend appears in (omitted if unconfirmed)"},
                         {RPCResult::Type::NUM, "height", /*optional=*/true, "Height of the spend (omitted if unconfirmed)"},
                         {RPCResult::Type::STR_HEX, "spend_txid", "The txid of the spending transaction"},
-                        {RPCResult::Type::NUM, "spend_vout", "The vout of the spend"},
+                        {RPCResult::Type::NUM, "spend_vin", "The vin of the spend"},
                         {RPCResult::Type::STR_HEX, "prevout_txid", "The txid of the prevout"},
                         {RPCResult::Type::NUM, "prevout_vout", "The vout of the prevout"},
                         {RPCResult::Type::OBJ, "prevout_spk", "", ScriptPubKeyDoc()},
@@ -3679,10 +3677,10 @@ static RPCHelpMan getsidechaininfo()
                     RPCResult::Type::OBJ, "", "",
                     {
                         {RPCResult::Type::STR_HEX, "fedpegscript", "The fedpegscript from genesis block"},
-                        {RPCResult::Type::ARR, "current_fedpegscripts", "The currently-enforced fedpegscripts in hex. Peg-ins for any entries on this list are honored by consensus and policy. Newest first. Two total entries are possible",
-                            {{RPCResult::Type::STR_HEX, "", "active fedpegscript"}}},
                         {RPCResult::Type::ARR, "current_fedpeg_programs", "The currently-enforced fedpegscript scriptPubKeys in hex. Prior to a transition this may be P2SH scriptpubkey, otherwise it will be a native segwit script. Results are paired in-order with current_fedpegscripts",
                             {{RPCResult::Type::STR_HEX, "", "active fedpegscript scriptPubKeys"}}},
+                        {RPCResult::Type::ARR, "current_fedpegscripts", "The currently-enforced fedpegscripts in hex. Peg-ins for any entries on this list are honored by consensus and policy. Newest first. Two total entries are possible",
+                            {{RPCResult::Type::STR_HEX, "", "active fedpegscript"}}},
                         {RPCResult::Type::STR_HEX, "pegged_asset", "Pegged asset type"},
                         {RPCResult::Type::STR, "min_peg_diff", "The minimum difficulty parent chain header target. Peg-in headers that have less work will be rejected as an anti-Dos measure"},
                         {RPCResult::Type::STR_HEX, "parent_blockhash", "The parent genesis blockhash as source of pegged-in funds"},
diff --git a/src/rpc/mining.cpp b/src/rpc/mining.cpp
index d620a28..40d7665 100644
--- a/src/rpc/mining.cpp
+++ b/src/rpc/mining.cpp
@@ -450,14 +450,14 @@ static RPCHelpMan getmininginfo()
                         {RPCResult::Type::NUM, "networkhashps", /*optional=*/true, "The network hashes per second"},
                         {RPCResult::Type::NUM, "pooledtx", "The size of the mempool"},
                         {RPCResult::Type::STR, "chain", "current network name (" LIST_CHAIN_NAMES ")"},
-                        {RPCResult::Type::STR_HEX, "signet_challenge", /*optional=*/true, "The block challenge (aka. block script), in hexadecimal (only present if the current network is a signet)"},
-                        {RPCResult::Type::OBJ, "next", "The next block",
+                        {RPCResult::Type::OBJ, "next", /*optional=*/true, "The next block",
                         {
                             {RPCResult::Type::NUM, "height", "The next height"},
                             {RPCResult::Type::STR_HEX, "bits", "The next target nBits"},
                             {RPCResult::Type::NUM, "difficulty", "The next difficulty"},
                             {RPCResult::Type::STR_HEX, "target", "The next target"}
                         }},
+                        {RPCResult::Type::STR_HEX, "signet_challenge", /*optional=*/true, "The block challenge (aka. block script), in hexadecimal (only present if the current network is a signet)"},
                         (IsDeprecatedRPCEnabled("warnings") ?
                             RPCResult{RPCResult::Type::STR, "warnings", "any network and blockchain warnings (DEPRECATED)"} :
                             RPCResult{RPCResult::Type::ARR, "warnings", "any network and blockchain warnings (run with `-deprecatedrpc=warnings` to return the latest warning as a single string)",
@@ -663,6 +663,10 @@ static RPCHelpMan getblocktemplate()
             RPCResult{"If the proposal was not accepted with mode=='proposal'", RPCResult::Type::STR, "", "According to BIP22"},
             RPCResult{"Otherwise", RPCResult::Type::OBJ, "", "",
             {
+                {RPCResult::Type::ARR, "capabilities", "",
+                {
+                    {RPCResult::Type::STR, "value", "A supported feature, for example 'proposal'"},
+                }},
                 {RPCResult::Type::NUM, "version", "The preferred block version"},
                 {RPCResult::Type::ARR, "rules", "specific block rules that are to be enforced",
                 {
@@ -672,10 +676,6 @@ static RPCHelpMan getblocktemplate()
                 {
                     {RPCResult::Type::NUM, "rulename", "identifies the bit number as indicating acceptance and readiness for the named softfork rule"},
                 }},
-                {RPCResult::Type::ARR, "capabilities", "",
-                {
-                    {RPCResult::Type::STR, "value", "A supported feature, for example 'proposal'"},
-                }},
                 {RPCResult::Type::NUM, "vbrequired", "bit mask of versionbits the server requires set in submissions"},
                 {RPCResult::Type::STR, "previousblockhash", "The hash of current highest block"},
                 {RPCResult::Type::ARR, "transactions", "contents of non-coinbase transactions that should be included in the next block",
@@ -1262,7 +1262,7 @@ static RPCHelpMan getnewblockhex()
     
     std::unique_ptr<CBlockTemplate> pblocktemplate(BlockAssembler(chainman.ActiveChainstate(), node.mempool.get(), options).CreateNewBlock());
     if (!pblocktemplate.get()) {
-        throw JSONRPCError(RPC_INTERNAL_ERROR, "Wallet keypool empty");
+        throw JSONRPCError(RPC_INTERNAL_ERROR, "Block template empty");
     }
 
     {
@@ -1310,7 +1310,7 @@ static RPCHelpMan combineblocksigs()
                             },
                         },
                     },
-                    {"witnessScript", RPCArg::Type::STR_HEX, RPCArg::Optional::OMITTED, "The hex-encoded witnessScript for the signblockscript"},
+                    {"witnessScript", RPCArg::Type::STR_HEX, RPCArg::Optional::OMITTED, "The hex-encoded witnessScript for the signblockscript. Required for dynafed blocks; omitted for non-dynafed blocks."},
                 },
                 RPCResult{
                     RPCResult::Type::OBJ, "", "",
@@ -1391,7 +1391,7 @@ static RPCHelpMan getcompactsketch()
                     {"block_hex", RPCArg::Type::STR_HEX, RPCArg::Optional::NO, "Hex serialized block proposal from `getnewblockhex`."},
                 },
                 RPCResult{
-                    RPCResult::Type::STR, "sketch", "serialized block sketch",
+                    RPCResult::Type::STR_HEX, "sketch", "serialized block sketch",
                 },
                 RPCExamples{
                     HelpExampleCli("getcompactsketch", ""),
diff --git a/src/rpc/rawtransaction.cpp b/src/rpc/rawtransaction.cpp
index d339fa5..1877d08 100644
--- a/src/rpc/rawtransaction.cpp
+++ b/src/rpc/rawtransaction.cpp
@@ -343,7 +343,7 @@ static RPCHelpMan getrawtransaction()
                 },
                 {
                     RPCResult{"if verbosity is not set or set to 0",
-                         RPCResult::Type::STR, "data", "The serialized transaction as a hex-encoded string for 'txid'"
+                         RPCResult::Type::STR_HEX, "data", "The serialized transaction as a hex-encoded string for 'txid'"
                      },
                      RPCResult{"if verbosity is set to 1",
                          RPCResult::Type::OBJ, "", "",
@@ -711,7 +711,7 @@ static RPCHelpMan combinerawtransaction()
                         },
                 },
                 RPCResult{
-                    RPCResult::Type::STR, "", "The hex-encoded raw transaction with signature(s)"
+                    RPCResult::Type::STR_HEX, "", "The hex-encoded raw transaction with signature(s)"
                 },
                 RPCExamples{
                     HelpExampleCli("combinerawtransaction", R"('["myhex1", "myhex2", "myhex3"]')")
@@ -795,7 +795,7 @@ static RPCHelpMan signrawtransactionwithkey()
                     {"hexstring", RPCArg::Type::STR, RPCArg::Optional::NO, "The transaction hex string"},
                     {"privkeys", RPCArg::Type::ARR, RPCArg::Optional::NO, "The base58-encoded private keys for signing",
                         {
-                            {"privatekey", RPCArg::Type::STR_HEX, RPCArg::Optional::OMITTED, "private key in base58-encoding"},
+                            {"privatekey", RPCArg::Type::STR, RPCArg::Optional::OMITTED, "private key in base58-encoding"},
                         },
                         },
                     {"prevtxs", RPCArg::Type::ARR, RPCArg::Optional::OMITTED, "The previous dependent transaction outputs",
@@ -1171,9 +1171,8 @@ static RPCHelpMan decodepsbt()
                         }},
                         {RPCResult::Type::NUM, "tx_version", /*optional=*/true, "The version number of the unsigned transaction. Not to be confused with PSBT version"},
                         {RPCResult::Type::NUM, "fallback_locktime", /*optional=*/true, "The locktime to fallback to if no inputs specify a required locktime."},
-                        {RPCResult::Type::NUM, "fees", "The fees specified in this psbt.", {}, /*skip_type_check=*/true}, // ELEMENTS has an explicit fee output, bitcoin does not (they are implicit)
-                        {RPCResult::Type::NUM, "input_count", "The number of inputs in this psbt"},
-                        {RPCResult::Type::NUM, "output_count", "The number of outputs in this psbt."},
+                        {RPCResult::Type::NUM, "input_count", /*optional=*/true, "The number of inputs in this psbt"},
+                        {RPCResult::Type::NUM, "output_count", /*optional=*/true, "The number of outputs in this psbt."},
                         {RPCResult::Type::BOOL, "inputs_modifiable", /*optional=*/true, "Whether inputs can be modified"},
                         {RPCResult::Type::BOOL, "outputs_modifiable", /*optional=*/true, "Whether outputs can be modified"},
                         {RPCResult::Type::BOOL, "has_sighash_single", /*optional=*/true, "Whether this PSBT has SIGHASH_SINGLE inputs"},
@@ -2608,7 +2607,7 @@ static RPCHelpMan rawblindrawtransaction()
                     {"ignoreblindfail", RPCArg::Type::BOOL, RPCArg::Default{true}, "Return a transaction even when a blinding attempt fails due to number of blinded inputs/outputs."},
                 },
                 RPCResult{
-                     RPCResult::Type::STR, "transaction", "hex string of the transaction"
+                     RPCResult::Type::STR_HEX, "transaction", "hex string of the transaction"
                 },
                 RPCExamples{""},
         [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
@@ -2642,7 +2641,7 @@ static RPCHelpMan rawblindrawtransaction()
     }
     if (inputAmounts.size() != tx.vin.size()) {
         throw JSONRPCError(RPC_INVALID_PARAMETER,
-            "Invalid parameter: one (potentially empty) input blind for each input must be provided");
+            "Invalid parameter: one (potentially empty) input amount for each input must be provided");
     }
     if (inputAssets.size() != tx.vin.size()) {
         throw JSONRPCError(RPC_INVALID_PARAMETER,
@@ -2694,7 +2693,7 @@ static RPCHelpMan rawblindrawtransaction()
         if (!IsHex(assetblind) || assetblind.length() != 32*2)
             throw JSONRPCError(RPC_INVALID_PARAMETER, "input asset blinds must be an array of 32-byte hex-encoded strings");
         if (!IsHex(asset) || asset.length() != 32*2)
-            throw JSONRPCError(RPC_INVALID_PARAMETER, "input asset blinds must be an array of 32-byte hex-encoded strings");
+            throw JSONRPCError(RPC_INVALID_PARAMETER, "input asset IDs must be an array of 32-byte hex-encoded strings");
 
         input_blinds.push_back(uint256S(blind));
         input_asset_blinds.push_back(uint256S(assetblind));
diff --git a/src/wallet/rpc/coins.cpp b/src/wallet/rpc/coins.cpp
index fd3bddc..2b004eb 100644
--- a/src/wallet/rpc/coins.cpp
+++ b/src/wallet/rpc/coins.cpp
@@ -120,7 +120,7 @@ RPCHelpMan getreceivedbyaddress()
             "\nThe amount with at least 6 confirmations\n"
             + HelpExampleCli("getreceivedbyaddress", "\"" + EXAMPLE_ADDRESS[0] + "\" 6") +
             "\nThe amount with at least 6 confirmations including immature coinbase outputs\n"
-            + HelpExampleCli("getreceivedbyaddress", "\"" + EXAMPLE_ADDRESS[0] + "\" 6 true") +
+            + HelpExampleCli("getreceivedbyaddress", "\"" + EXAMPLE_ADDRESS[0] + "\" 6 \"\" true") +
             "\nAs a JSON-RPC call\n"
             + HelpExampleRpc("getreceivedbyaddress", "\"" + EXAMPLE_ADDRESS[0] + "\", 6")
                 },
@@ -178,9 +178,9 @@ RPCHelpMan getreceivedbylabel()
             "\nThe amount with at least 6 confirmations\n"
             + HelpExampleCli("getreceivedbylabel", "\"tabby\" 6") +
             "\nThe amount with at least 6 confirmations including immature coinbase outputs\n"
-            + HelpExampleCli("getreceivedbylabel", "\"tabby\" 6 true") +
+            + HelpExampleCli("getreceivedbylabel", "\"tabby\" 6 \"\" true") +
             "\nAs a JSON-RPC call\n"
-            + HelpExampleRpc("getreceivedbylabel", "\"tabby\", 6, true")
+            + HelpExampleRpc("getreceivedbylabel", "\"tabby\", 6, \"\", true")
                 },
         [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
 {
@@ -640,14 +640,14 @@ RPCHelpMan listunspent()
                             {RPCResult::Type::STR, "scriptPubKey", "the output script"},
                             {RPCResult::Type::STR_AMOUNT, "amount", "the transaction output amount in " + CURRENCY_UNIT},
                             {RPCResult::Type::STR_HEX, "amountcommitment", /*optional=*/true, "the transaction output commitment in hex"},
-                            {RPCResult::Type::STR_HEX, "asset", "the transaction output asset in hex"},
+                            {RPCResult::Type::STR_HEX, "asset", /*optional=*/true, "the transaction output asset in hex"},
                             {RPCResult::Type::STR_HEX, "assetcommitment", /*optional=*/true, "the transaction output asset commitment in hex"},
-                            {RPCResult::Type::STR_HEX, "amountblinder", "the transaction output amount blinding factor in hex"},
-                            {RPCResult::Type::STR_HEX, "assetblinder", "the transaction output asset blinding factor in hex"},
+                            {RPCResult::Type::STR_HEX, "amountblinder", /*optional=*/true, "the transaction output amount blinding factor in hex"},
+                            {RPCResult::Type::STR_HEX, "assetblinder", /*optional=*/true, "the transaction output asset blinding factor in hex"},
                             {RPCResult::Type::NUM, "confirmations", "The number of confirmations"},
                             {RPCResult::Type::NUM, "ancestorcount", /*optional=*/true, "The number of in-mempool ancestor transactions, including this one (if transaction is in the mempool)"},
                             {RPCResult::Type::NUM, "ancestorsize", /*optional=*/true, "The virtual transaction size of in-mempool ancestors, including this one (if transaction is in the mempool)"},
-                            {RPCResult::Type::STR_AMOUNT, "ancestorfees", /*optional=*/true, "The total fees of in-mempool ancestors (including this one) with fee deltas used for mining priority in " + CURRENCY_ATOM + " (if transaction is in the mempool)"},
+                            {RPCResult::Type::NUM, "ancestorfees", /*optional=*/true, "The total fees of in-mempool ancestors (including this one) with fee deltas used for mining priority in " + CURRENCY_ATOM + " (if transaction is in the mempool)"},
                             {RPCResult::Type::STR_HEX, "redeemScript", /*optional=*/true, "The redeem script if the output script is P2SH"},
                             {RPCResult::Type::STR, "witnessScript", /*optional=*/true, "witness script if the output script is P2WSH or P2SH-P2WSH"},
                             {RPCResult::Type::BOOL, "spendable", "Whether we have the private keys to spend this output"},
diff --git a/src/wallet/rpc/elements.cpp b/src/wallet/rpc/elements.cpp
index 455c559..3ae2400 100644
--- a/src/wallet/rpc/elements.cpp
+++ b/src/wallet/rpc/elements.cpp
@@ -1000,7 +1000,7 @@ RPCHelpMan createrawpegin()
                 RPCResult{
                     RPCResult::Type::OBJ, "", "",
                     {
-                        {RPCResult::Type::STR, "hex", "raw transaction data"},
+                        {RPCResult::Type::STR_HEX, "hex", "raw transaction data"},
                         {RPCResult::Type::BOOL, "mature", /*optional=*/true, "Whether the peg-in is mature (only included when validating peg-ins)"},
                     },
                 },
diff --git a/src/wallet/rpc/spend.cpp b/src/wallet/rpc/spend.cpp
index b044140..393d047 100644
--- a/src/wallet/rpc/spend.cpp
+++ b/src/wallet/rpc/spend.cpp
@@ -1001,7 +1001,7 @@ RPCHelpMan signrawtransactionwithwallet()
                                     {"redeemScript", RPCArg::Type::STR_HEX, RPCArg::Optional::OMITTED, "(required for P2SH) redeem script"},
                                     {"witnessScript", RPCArg::Type::STR_HEX, RPCArg::Optional::OMITTED, "(required for P2WSH or P2SH-P2WSH) witness script"},
                                     {"amount", RPCArg::Type::AMOUNT, RPCArg::Optional::OMITTED, "The amount spent (required if non-confidential segwit output)"},
-                                    {"amountcommitment", RPCArg::Type::STR, RPCArg::Optional::OMITTED, "The amount commitment spent (required if confidential segwit output)"},
+                                    {"amountcommitment", RPCArg::Type::STR_HEX, RPCArg::Optional::OMITTED, "The amount commitment spent (required if confidential segwit output)"},
                                 },
                             },
                         },
@@ -1917,7 +1917,7 @@ RPCHelpMan walletcreatefundedpsbt()
                         FundTxDoc()),
                         RPCArgOptions{.oneline_description="options"}},
                     {"bip32derivs", RPCArg::Type::BOOL, RPCArg::Default{true}, "Include BIP 32 derivation paths for public keys if we know them"},
-                    {"psbt_version", RPCArg::Type::NUM, RPCArg::Default{2}, "The PSBT version number to use."},
+                    {"psbt_version", RPCArg::Type::NUM, RPCArg::Default{2}, "The PSBT version number to use. Must be 2."},
                 },
                 RPCResult{
                     RPCResult::Type::OBJ, "", "",
diff --git a/src/wallet/rpc/wallet.cpp b/src/wallet/rpc/wallet.cpp
index f4d1400..14ee67f 100644
--- a/src/wallet/rpc/wallet.cpp
+++ b/src/wallet/rpc/wallet.cpp
@@ -52,16 +52,13 @@ static RPCHelpMan getwalletinfo()
                         {RPCResult::Type::NUM, "walletversion", "the wallet version"},
                         {RPCResult::Type::STR, "format", "the database format (bdb or sqlite)"},
                         {RPCResult::Type::OBJ, "balance", "DEPRECATED. Identical to getbalances().mine.trusted", {
-                            // A different entry for each asset in the wallet
-                            {RPCResult::Type::STR_AMOUNT, "bitcoin", "amount of bitcoin in the wallet"},
+                            {RPCResult::Type::ELISION, "", "the amount for each asset"},
                         }, /*skip_type_check=*/true},
                         {RPCResult::Type::OBJ, "unconfirmed_balance", "DEPRECATED. Identical to getbalances().mine.untrusted_pending", {
-                            // A different entry for each asset in the wallet
-                            {RPCResult::Type::STR_AMOUNT, "bitcoin", "amount of bitcoin in the wallet"},
+                            {RPCResult::Type::ELISION, "", "the amount for each asset"},
                         }, /*skip_type_check=*/true},
                         {RPCResult::Type::OBJ, "immature_balance", "DEPRECATED. Identical to getbalances().mine.immature", {
-                            // A different entry for each asset in the wallet
-                            {RPCResult::Type::STR_AMOUNT, "bitcoin", "amount of bitcoin in the wallet"},
+                            {RPCResult::Type::ELISION, "", "the amount for each asset"},
                         }, /*skip_type_check=*/true},
                         {RPCResult::Type::NUM, "txcount", "the total number of transactions in the wallet"},
                         {RPCResult::Type::NUM_TIME, "keypoololdest", /*optional=*/true, "the " + UNIX_EPOCH_TIME + " of the oldest pre-generated key in the key pool. Legacy wallets only."},
diff --git a/test/functional/feature_blocksign.py b/test/functional/feature_blocksign.py
index 0306902..1dbd293 100755
--- a/test/functional/feature_blocksign.py
+++ b/test/functional/feature_blocksign.py
@@ -180,6 +180,39 @@ class BlockSignTest(BitcoinTestFramework):
         for i in range(num_blocks):
             self.mine_block(transactions)
 
+    def test_combineblocksigs_witnessscript_arg(self):
+        # Regression test for combineblocksigs witnessScript optionality.
+
+        node = self.nodes[0]
+        block = node.getnewblockhex()
+
+        is_dyna = node.getdeploymentinfo()['deployments']['dynafed']['bip9']['status'] == "active"
+
+        if is_dyna:
+            # no witnessScript must give RPC_INVALID_PARAMETER, not a help error from arg-count validation.
+            assert_raises_rpc_error(
+                -8,
+                "Signing dynamic blocks requires the witnessScript argument",
+                node.combineblocksigs,
+                block,
+                [],
+            )
+            # Supplying witnessScript must work normally.
+            result = node.combineblocksigs(block, [], self.witnessScript)
+            assert "hex" in result
+            assert "complete" in result
+        else:
+            # Non-dynafed: 2-argument call must not be rejected by arg-count validation. 
+            try:
+                result = node.combineblocksigs(block, [])
+                assert "hex" in result
+                assert "complete" in result
+            except Exception as e:
+                # If exception it must not be the help string
+                assert "combineblocksigs" not in str(e), \
+                    "Got help text — 2-arg call was rejected by arg-count validation"
+                raise
+
     def run_test(self):
         # Have every node except last import its block signing private key.
         for i in range(self.num_keys):
@@ -211,6 +244,10 @@ class BlockSignTest(BitcoinTestFramework):
 
         assert_equal(info['deployments']['dynafed']['bip9']['status'], "defined")
 
+        # Test combineblocksigs witnessScript optionality pre-dynafed
+        self.log.info("Testing combineblocksigs witnessScript argument (pre-dynafed)")
+        self.test_combineblocksigs_witnessscript_arg()
+
         # Next let's activate dynafed
         blocks_til_dynafed = 431 - self.nodes[0].getblockcount()
         self.log.info("Activating dynafed")
@@ -221,6 +258,11 @@ class BlockSignTest(BitcoinTestFramework):
 
         self.log.info("Mine some dynamic federation blocks without txns")
         self.mine_blocks(10, False)
+
+        # Test combineblocksigs witnessScript optionality post-dynafed
+        self.log.info("Testing combineblocksigs witnessScript argument (post-dynafed)")
+        self.test_combineblocksigs_witnessscript_arg()
+
         self.log.info("Mine some dynamic federation blocks with txns")
         self.mine_blocks(10, True)