check_connection

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

With no annotations, the description carries the burden of explaining behavior. It discloses that the tool tests the API key and returns rate limit headroom, implying a read-only, non-destructive operation. It does not detail error responses or output structure, but for a zero-parameter health check, the essential behavior is transparent.

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 a single focused sentence with no filler. It front-loads the core action ('verify the API key works') and the secondary result ('report rate limit headroom'), earning its place entirely.

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?

For a zero-parameter tool with no output schema, the description provides the core purpose and the key output concept. It lacks explicit return field names or failure behavior, but for a simple connection check the description is sufficiently complete.

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?

The input schema has zero properties, so there are no parameters to document. Achieves the baseline 4 for a zero-parameter tool since no parameter description is needed.

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 states a specific verb ('verify'), a resource ('API key'), and the outcome ('report rate limit headroom'). This clearly distinguishes it from sibling tools like list_activities or get_athlete_profile, which concern data retrieval rather than connection status.

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?

The description implies the tool is for checking API connectivity and rate limits, which is distinct from all siblings. There is no explicit 'use when' or alternative routing, but the unique purpose provides clear context without needing exclusions.

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