Bitcoin-MCP

get_mempool_ancestors

Retrieve all unconfirmed ancestor transactions for a given mempool transaction to analyze CPFP (Child Pays For Parent) scenarios and understand transaction dependencies.

Instructions

Get all unconfirmed ancestor transactions of a mempool transaction. Useful for CPFP analysis.

Args: txid: Transaction hash (64 hex characters)

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "txid": "<txid>"
    },
    "name": "get_mempool_ancestors"
  }
}

Input Schema

Name	Required	Description	Default
`txid`	Yes

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.5.1Apr 2, 2026

TDQS

A3.5/5.0

Behavior2/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden. It mentions the tool is 'useful for CPFP analysis,' which adds some behavioral context about its application. However, it lacks details on permissions, rate limits, output format, or error handling. For a tool with no annotations, this is a significant gap in transparency.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is appropriately sized and front-loaded. The first sentence states the purpose clearly, the second adds usage context, and the 'Args' section efficiently documents the parameter. Every sentence earns its place with no wasted words, making it easy to scan and understand.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's moderate complexity (one parameter, no annotations, but with an output schema), the description is fairly complete. It explains the purpose, usage, and parameter semantics. Since an output schema exists, it doesn't need to detail return values. However, it could improve by mentioning prerequisites (e.g., transaction must be in mempool) or error cases.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The description adds meaningful semantics beyond the input schema. The schema has 0% description coverage and only defines 'txid' as a string. The description specifies that 'txid' is a 'Transaction hash (64 hex characters),' providing crucial format details. With one parameter and low schema coverage, this compensation is effective, though it could note if the hash must be lowercase or valid.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose: 'Get all unconfirmed ancestor transactions of a mempool transaction.' It specifies the verb ('Get') and resource ('unconfirmed ancestor transactions'), and distinguishes it from siblings like 'get_mempool_entry' or 'analyze_mempool' by focusing on ancestor relationships. However, it doesn't explicitly differentiate from all siblings, such as 'get_mempool_info'.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides implied usage context: 'Useful for CPFP analysis.' This suggests when to use the tool (for analyzing Child-Pays-For-Parent scenarios), but it doesn't explicitly state when not to use it or name alternatives. For example, it doesn't clarify if this is for unconfirmed transactions only or how it differs from 'analyze_transaction'.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Deploy Server