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WORKS SAAS

Forecall

Measures whether AI agents choose and call your MCP tools correctly, and shows what to fix. The tool-description linter is open source.

Overview

How an agent calls an MCP tool depends on how the tool is described. Forecall starts with a linter that scores tool descriptions from 0 to 100, then measures whether agents actually choose and call the tools correctly, and shows what to fix.

Pieces

  • forecall-cli: npx forecall lint tools.json scores each tool on purpose, when to use it, arguments, return value, constraints and examples. Open source, with a GitHub Action
  • forecall-mcp: a small relay that connects stdio-only clients such as Claude Desktop to the Forecall Failure KB, an MCP server where agents look up known failures and workarounds before and after calling a tool
  • forecall.dev: the measurement service and dashboard

Technical notes

  • Scoring rules are versioned and separate server-wide issues (near-identical descriptions) from per-tool ones
  • The KB is a Streamable HTTP MCP server; the relay exists only for clients that cannot reach a remote server