Intervals.icu MCP Server

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries full burden. It states 'Delete' implying a destructive mutation but doesn't disclose behavioral traits like whether deletion is permanent, requires specific permissions, has rate limits, or what the output contains. This is inadequate for a mutation tool with zero annotation coverage.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is appropriately sized and front-loaded with the core purpose, followed by parameter details. The Args section is structured but slightly verbose; every sentence earns its place by clarifying parameter behavior.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given a destructive mutation tool with no annotations, 3 parameters (0% schema coverage), and an output schema (which reduces need to describe returns), the description is partially complete. It covers parameters well but lacks behavioral context like safety warnings or usage scenarios, leaving gaps for agent understanding.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description must compensate. It provides clear semantics for all 3 parameters: 'event_id' as the event ID to delete, and optional 'athlete_id' and 'api_key' with fallback to environment variables. This adds essential meaning beyond the bare schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb 'Delete' and resource 'event for an athlete from Intervals.icu', making the purpose unambiguous. It distinguishes from siblings like 'delete_events_by_date_range' by specifying single event deletion, though not explicitly contrasting them.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance on when to use this tool versus alternatives like 'delete_events_by_date_range' or 'add_or_update_event'. The description only lists parameters without contextual usage advice, prerequisites, or exclusions.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.