stx_sign_transaction · Bitcoin wallet MCP server MCP

WHAT IT DOES

What stx_sign_transaction does on Bitcoin wallet MCP server

AI agents invoke stx_sign_transaction to trigger actions in Bitcoin wallet MCP server. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why stx_sign_transaction needs a policy

Signing a transaction is a critical step that authorizes and commits to a blockchain operation. While signing itself doesn't broadcast/send funds, it is an irreversible cryptographic authorization that enables a financial transaction to be executed.

From the tool's definition Sign a serialized Stacks transaction (SIP-30 compatible)

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

stx_sign_transaction Rate-limited

stx_sign_transaction stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "stx_sign_transaction": {
      "limits": [
        {
          "counter": "stx_sign_transaction_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Bitcoin wallet MCP server, so you can run agents against it safely.

FAQ

Questions about stx_sign_transaction

What does the stx_sign_transaction tool do? +

Sign a serialized Stacks transaction (SIP-30 compatible). It is categorised as a Execute tool in the Bitcoin wallet MCP server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on stx_sign_transaction? +

Register the Bitcoin wallet MCP server MCP server in PolicyLayer and add a rule for stx_sign_transaction: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Bitcoin wallet MCP server. Nothing to install.

What risk level is stx_sign_transaction? +

stx_sign_transaction is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit stx_sign_transaction? +

Yes. Add a rate_limit block to the stx_sign_transaction rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.

How do I block stx_sign_transaction completely? +

Set action: deny in the PolicyLayer policy for stx_sign_transaction. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.

What MCP server provides stx_sign_transaction? +

stx_sign_transaction is provided by the Bitcoin wallet MCP server MCP server (markmhendrickson/mcp-server-bitcoin). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.