Paper Distill MCP has moderate definition quality with significant gaps. Tool names are clear and action-focused (search_, rank_, filter_, generate_, send_, collect_, manage_). Descriptions are present but vary in quality, some are detailed and specific (search_papers, send_push with platform enum), others are vague about error handling and recovery. Parameter schemas are visible with types declared, but descriptions lack actionable constraints. Critical issues: (1) No error handling guidance in any tool, LLMs cannot recover from failures (pattern:recovery-guide missing). (2) No output schema documentation, tools return dicts/lists but structure is not formally described. (3) Missing nullable/default handling for optional params. (4) No idempotency guarantees for stateful tools (generate_digest, send_push). (5) Security concern: credentials (tokens, webhook URLs) are loaded from environment but there is no documentation of required scope/permissions per tool. (6) Some parameters lack type details: 'topics' in generate_digest is 'dict | None' but no schema for the dict structure.

• Add formal JSON Schema output definitions to all tools. Example for search_papers: document that response is array of {title: string, year: int, doi: string, authors: array, abstract: string, source: string, citation_count: int}. Place schema in tool description or as a dedicated 'outputSchema' field if fastmcp supports it.
• Document error modes and recovery paths in every tool description. Example for send_push: 'Error: Missing platform token. Call send_push with a different platform, or configure TELEGRAM_BOT_TOKEN in environment. Retryable: yes, after fixing credentials.'
• Add min/max constraints to numeric parameters. Example: max_results: 'int, 1 - 100 (default 10)', weight: 'float, 0.0 - 1.0'.
• Specify parameter formats in descriptions. Example: date param, 'String in ISO 8601 format YYYY-MM-DD. Example: 2024-12-31. Note: Must be a valid date; invalid dates return error with reason.'
• Document the schema of nested/complex parameters. Example: papers array, 'Array of paper objects, each with keys: doi (string), title (string), year (int), abstract (string), authors (array of strings), citation_count (int). DOI is required for deduplication.'
• Add idempotency keys or duplicate detection to WRITE tools. Example: send_push should accept optional idempotency_key parameter (or hash the date+platform+papers to generate one). Return the key so agents can retry safely.
• Implement dry-run/preview mode for destructive/high-impact operations. Example: send_push with 'dry_run=true' returns formatted message without sending. Or add 'preview_push' tool that returns the formatted message, and agents can call send_push after review.

Inferred effective spec: <=2025-11-25.

• Relies on Logging (deprecated) - log to stderr or use OpenTelemetry