Oura MCP demonstrates solid fundamentals with clear verb-based naming (oura_authenticate, oura_api_get) and consistent tool annotations. All 5 tools have descriptions (avg ~120 chars) and input schemas with Zod validation. However, parameter descriptions lack depth, many omit format constraints, valid ranges, or dependency hints. The generic oura_api_get tool accepts flexible params but provides minimal guidance on endpoint-specific requirements (date formats, pagination behavior). Error handling returns text-only responses without structured recovery guidance. Output schema for oura_api_get is well-defined (status, data, next_token, pages_fetched, has_more) but other tools lack documented return structures. No batch operations or natural-identifier support (e.g., accepting user-friendly date ranges vs ISO strings).

• Add structured output schema to oura_api_list_paths: return {endpoints: [{path: string, summary: string, params: string[]}]} instead of plain text. Enables LLM to programmatically select endpoints.
• Enhance oura_api_get param descriptions with endpoint-specific guidance: 'For daily endpoints (e.g., /v2/usercollection/daily_sleep), use start_date/end_date (YYYY-MM-DD). For time-series (e.g., /v2/timeseries/heart_rate), use start_datetime/end_datetime (ISO 8601).'
• Implement structured error responses: return {error: {code: string, message: string, retryable: boolean, suggestion: string}} instead of isError flag + text. Enables LLM to classify and recover.
• Document output schemas for auth tools: oura_authenticate → {url: string, expires_at: number}, oura_auth_status → {authenticated: boolean, expires_at: number, scope: string}, oura_clear_auth → {success: boolean}.
• Add a dry_run parameter to oura_api_get (default false) to preview results without consuming rate limits, reducing agent trial-and-error on unfamiliar endpoints.

Inferred effective spec: 2025-06-18+.

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