Myelin

API Reference

Myelin exposes three MCP tools. All are called through the standard MCP tool-calling interface.

search

Search for matching workflows. Call this to find relevant procedures before starting a task.

Parameters

{
  "task_description": "string (required) — natural language description of the task.
    Keep procedural detail (steps, output format); omit variable values
    (file paths, names, IDs) that change between uses."
}

Response

Returns matching workflows with overview and step summaries:

Reset a user's password via the admin panel.

Steps:
1) Look up user by email
2) Trigger password reset
3) Confirm reset email sent

If no workflows match, returns an empty result.

record

Begin a recording session for a task. Call this at the beginning of any task you want Myelin to learn from.

Parameters

{
  "task_description": "string (optional) — natural language description of the task",
  "workflow_id": "string (optional) — workflow ID from search results, if a match was found"
  // At least one of task_description or workflow_id is required.
}

Response

session_id: ses_abc123

Recording started. When done, call finish(session_id).

Behavior

  • If a workflow_id is provided, the session is linked to that workflow. The agent should follow the procedure returned by search.
  • If no workflow_id is provided, the agent works freestyle. The session still records tool calls for potential workflow extraction.

finish

Finalize a recording session and queue it for server-side evaluation. Call this after the task is complete.

Parameters

{
  "session_id": "string (required) — the session_id from record"
}

Response

{
  "session_id": "ses_abc123",
  "tool_calls_recorded": 5,
  "status": "queued",
  "workflow_id": "wf_xyz789"  // present if a workflow was matched
}

Behavior

The server evaluates the session independently using an LLM judge that reviews the recorded tool calls and produces categorical verdicts:

  • With workflow — The evaluator judges task completion (success / partial / failure) and workflow adherence (followed / partial / diverged). The workflow's success rate is updated.
  • Without workflow — The evaluator judges task completion only. If the verdict is success, a new workflow is extracted from the session trace and queued for approval in the dashboard.

Error Codes

401  Unauthorized — invalid or missing API key
400  Bad Request — missing required parameter
404  Not Found — session_id does not exist or is not active
429  Rate Limited — too many requests
500  Internal Server Error