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  1. Servers
  3. Letter AI

Letter AI

io.github.tractatus-ai/letter

Search and act on Letter AI sales enablement content, deals, and call recordings.

SearchContent & Media

Findings

  • (connection) · transport

    Streamable HTTP error: Error POSTing to endpoint: {"error":"invalid_token","error_description":"API key auth failed: Missing Authorization header"}

Check history

updated 3h ago·re-checked weekly

DateGradeErrorsWarnings
2026-08-24unreachable——

Graded by connecting to the live server and validating every tool schema. Grades re-run on every sync. Findings and grades are never editable by the publisher.

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Kick the tires on your own server: run a check

Grade
–

Not graded: unreachable on the last check.

How grading works

Install

Claude Code (remote)

claude mcp add --transport http io-github-tractatus-ai-letter https://api.letter.ai/v1/mcp

Endpoint (streamable HTTP)

https://api.letter.ai/v1/mcp

Verify it yourself

npx tirekick check https://api.letter.ai/v1/mcp
Links
  • MCP registry entry
  • Your server? Claim this listing