# Bitcoin Core verifymessage RPC via x402

> Bitcoin Core verifymessage RPC via x402 is a paid API for AI agents from x402.chainquery.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15).

Verifies a message signed by the private key behind a Bitcoin address using Bitcoin Core's verifymessage RPC, accessed pay-per-call with no API key.

## Facts

- Endpoint: GET https://x402.chainquery.com/v1/rpc/verifymessage
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/bitcoin-core-verifymessage-rpc-via-x402-7bedf78d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_qEc61LIISJVa9bu7pGMyg

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability bitcoin-core-verifymessage-rpc-via-x402-7bedf78d
```

Example prompt: Can you verify whether the Bitcoin address 1A1zP1eP5QGefi2DMPTfTL5SLmv7Divf NA actually signed the message 'Hello world' with the signature HxTpDpOa3Uh6...?

## When to prefer this

Choose this endpoint when you need to cryptographically verify that a specific Bitcoin address owner signed a specific message, without needing your own Bitcoin node or API key — ideal for agent workflows that need trustless Bitcoin signature verification at low per-call cost via x402 micropayment.

## Known failure modes

- Invalid or malformed Bitcoin address returns an RPC error
- Incorrect or malformed base64 signature returns false or RPC error
- Missing required params (address, message, signature) causes a 400 or RPC error
- Payment failure or insufficient USDC balance returns a 402 status
- Malformed JSON in params query parameter causes a parsing error

## How this service works

chainquery Bitcoin RPC: pay-per-call Bitcoin Core over x402, no API key. Verify a message signed by the private key behind a Bitcoin address. Bitcoin Core verifymessage.

## Output

Returns a boolean result indicating whether the provided signature is valid for the given message and Bitcoin address — true if the signature is authentic, false otherwise.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "params": {
       "type": "string",
       "description": "optional: JSON-encoded array of positional RPC params"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "result": {
       "description": "verifymessage result"
      }
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/bitcoin-core-verifymessage-rpc-via-x402-7bedf78d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.chainquery.com](https://www.zero.xyz/host/x402.chainquery.com/llms.txt)