Bitcoin — BizFirstAI Node Reference

What it does: The Bitcoin node (bitcoin) reads chain data — addresses, transactions, blocks, mempool, fee estimates — from a real Esplora-compatible block-explorer API (Blockstream.info by default), and builds, signs, combines, finalizes, extracts, and broadcasts real Bitcoin transactions through a BIP-174 PSBT (Partially Signed Bitcoin Transaction) pipeline built on NBitcoin. Read operations need no credential; PSBT signing and message signing need a vault-resolved WIF key or BIP-39 mnemonic.

Quick Start

Add a Bitcoin node to your workflow
Set resource to address and operation to getInfo
Enter an address (e.g. a mainnet bc1q… address)
Set network to mainnet, testnet, signet, or regtest
Run the workflow — the node returns the address's confirmed balance, tx count, and totals

Tip: Every operation shares the same three config keys — resource, operation, network — plus a small set of operation-specific fields. Learn the pattern once on Input & Output, and if you're sending real Bitcoin, read PSBT Signing Pipeline before your first write — it covers the fund-safety rule every signing call enforces.

Pages in This Guide

Configuration

appsettings.json, coin-selection policy, UTXO reservation, and dependency registration.

Networks

Mainnet, testnet, signet, regtest, and the Esplora endpoint each one hits.

Address Operations

getInfo, getTransactions, getTransactionsChain, getTransactionsMempool, getUtxos.

Transaction Operations

get, getStatus, getHex, getMerkleProof, getOutspend(s), and broadcast.

Block Operations

get, getStatus, getTransactions, getTransactionId, getRaw, getHeader, getHash, and more.

Mempool Operations

getInfo, getTransactionIds, getRecent — unconfirmed transaction visibility.

Fee Estimates

getEstimates — sat/vB fee rates by confirmation target.

PSBT Signing Pipeline

build, sign, combine, finalize, extract — the full write path, plus its fund-safety rule.

Wallet Operations

deriveAddress, signMessage, verifySignature (BIP-137).

Input & Output

The shared config-key pattern, credential resolution, and how errors surface.

Examples

Worked workflow patterns — a read-only balance check and a full send-Bitcoin pipeline.

Troubleshooting

Common errors, their codes, and how to fix them.

Roadmap

The Taproot script-path spike, tests, and other unfinished work.

Core Concepts

Esplora Reads

Every read operation on this node queries an Esplora-compatible REST API (Blockstream.info by default) — free, public, and requiring no wallet or signing key. Esplora indexes both confirmed chain state and the live mempool, so some operations (like address/getTransactionsMempool) surface unconfirmed activity directly.

Resources

34 operations are grouped into 7 resources:

address (5 ops) — balances, transaction history, and spendable UTXOs
transaction (7 ops) — lookups, status, hex, merkle proofs, spend status, and broadcast
block (9 ops) — block metadata, contents, and chain-tip browsing
mempool (3 ops) — unconfirmed-transaction visibility
fee (1 op) — sat/vB fee-rate estimates by confirmation target
psbt (6 ops) — the build → sign → combine → finalize → extract write pipeline
wallet (3 ops) — key-derived addresses and BIP-137 message signing/verification

Reads vs. Writes

address, transaction (except broadcast), block, mempool, and fee are all free reads — no credential needed. psbt, wallet, and transaction/broadcast move or sign real funds; signing operations require a vault credentialID. See Input & Output for credential resolution and PSBT Signing Pipeline for the fund-safety rule every sign call enforces.

Networks

Every operation runs against one of four Bitcoin networks, selected per-call via the network config key — required on every write/signing operation. See Networks for URLs and defaults.

Operation Summary

Resource	Operations	Guide Page
`address`	`getInfo`, `getTransactions`, `getTransactionsChain`, `getTransactionsMempool`, `getUtxos`	Address Operations
`transaction`	`get`, `getStatus`, `getHex`, `getMerkleProof`, `getOutspend`, `getOutspends`, `broadcast`	Transaction Operations
`block`	`get`, `getStatus`, `getTransactions`, `getTransactionId`, `getRaw`, `getHeader`, `getHash`, `getRecentBlocks`, `getBlocksFromHeight`	Block Operations
`mempool`	`getInfo`, `getTransactionIds`, `getRecent`	Mempool Operations
`fee`	`getEstimates`	Fee Estimates
`psbt`	`build`, `sign`, `combine`, `finalize`, `extract`, `buildTaprootScriptPathInput`	PSBT Signing Pipeline
`wallet`	`deriveAddress`, `signMessage`, `verifySignature`	Wallet Operations

PSBT06 (buildTaprootScriptPathInput) is not fully implemented. It returns a clear PSBT_TAPROOT_SPIKE_PENDING error for the script-multisig-leaf case pending a dedicated NBitcoin spike. Key-path Taproot (P2TR) signing via psbt/sign and psbt/build is fully implemented. See Roadmap.