The server provides 5 tools with mixed quality. Tool names are action-oriented (prepare_, get_, list_, validate_, upload_), which is good. However, descriptions vary significantly in completeness. Parameter schemas are present but lack detailed descriptions for most parameters. The two read-only data retrieval tools (prepare_week_data, get_latest_activities) have better structure, while the utility tools (validate_week_plan, upload_week_plan) are sparse on parameter guidance. No output schemas are documented in the visible code, forcing LLMs to infer response structure. Error handling is minimal, no recovery guidance, categorization, or actionable error messages visible.

• Add explicit JSON Schema definitions for all tool outputs. Include field names, types, and descriptions so LLMs understand response structure without guessing.
• Expand parameter descriptions to 50-150 chars each. For 'limit', specify bounds (e.g., '1-100'); for 'match_mode', declare enum values; for 'plan_json', describe the expected schema or link to a specification.
• Add a 'Schema & Output' section to each tool description. Example: 'Returns a list of Activity objects with fields: id (string), date (ISO 8601), duration (seconds), type (string).'
• Implement error guidance. Tools should return errors like 'Invalid match_mode: must be "any" or "all"' instead of generic 400 errors. Add recovery hints: 'No workouts found. Try removing tag filters or call search_library_workouts() with broader criteria.'
• For write operations, add explicit warnings. Example: 'upload_week_plan uploads a plan to intervals.icu, overwriting any existing plan for that week. Consider calling validate_week_plan first.'
• Expand short descriptions. 'get_latest_activities' → 'Retrieve the most recent completed activities (rides, runs, etc.). Use this to see recent training data before planning. Limited to <X> most recent activities; use prepare_week_data for historical analysis.'
• Add pagination guidance. 'list_library_workouts accepts a limit parameter (1-100, default 20). If more results exist, call again with increased limit or implement offset-based pagination.'
• Document required dependencies between tools. Example: 'upload_week_plan typically follows validate_week_plan. Validation catches errors before upload.'

Inferred effective spec: 2026-07-28+.

• Relies on Dynamic Client Registration (deprecated) - use Client ID Metadata Documents (CIMD)