EverMint MCP exposes 5 tools with complete input schemas and descriptions. Naming follows verb_noun convention (mint, verify, list_records, get_record, verify_chain). Descriptions are present but brief (10-50 chars), below the 50-200 char baseline for LLM-optimized docs. All parameters have type definitions and descriptions. However, output schemas are not documented, LLMs cannot predict response structure for downstream chaining. Error handling is present but generic (HTTP status codes without recovery guidance). No parameter constraints (enums, ranges) despite several free-form string fields (action_type, agent_id) that could hallucinate invalid values. Missing idempotency guidance for the mint tool, which performs irreversible writes.

• Expand tool descriptions to 80-150 chars. Include WHEN to use (e.g. 'Call mint() after each agent action to create an immutable audit trail'), WHAT it returns (e.g. 'Returns record_id, SHA-256 hash, and chain link for verification'), and any prerequisites (e.g. 'Requires EVERMINT_API_KEY environment variable').
• Document output schemas in tool definitions. Add a 'returns' field describing MintResponse (record_id: string, sha256: string, timestamp: string, chain_link: string, status: string, credits_remaining: number) and VerifyResponse (found: boolean, record_id?: string, content_hash?: string, hash_algorithm?: string, submitted_at?: string, status?: string).
• Add parameter constraints: action_type as enum of valid action types (e.g. ['create', 'update', 'delete', 'execute', 'verify']), record_id with pattern '^EVR-[A-Z0-9]{8}$', limit with min=1 max=100.
• Enhance error messages with recovery guidance. Replace 'Verification failed: HTTP 404' with 'Record EVR-XXXXXXXX not found. Verify the Record ID format or call list_records(agent_id=...) to find valid records.'
• Add idempotency note to mint tool: 'Calling mint() twice with identical action_type and payload will create two separate records. Use the returned record_id to deduplicate on the client side if needed.'