garmin_personal_records

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

Annotations declare readOnlyHint=true and openWorldHint=true, which already convey the read-only nature and dynamic results. The description adds no behavioral context beyond that, such as whether records are aggregated or per-activity, or if results can be empty. Since annotations cover the basic safety profile, the description's minimal addition earns a baseline score of 3.

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, succinct sentence with no fluff. It is front-loaded with the core purpose and is appropriately sized for a parameterless tool. There is no wasted text, and it is easy to scan.

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 the low complexity (0 params, no output schema) and existing annotations, the description is minimal but not fully complete. It tells the agent what the tool returns (personal records) but not the format, granularity, or whether it's a list or single object. An agent might call it confidently, but without more context, the response shape is unpredictable, making this a borderline acceptable but not thorough description.

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 tool has zero parameters, so the schema provides nothing to explain. According to the rubric, 0 params earns a baseline of 4. The description does not need to compensate for missing parameter docs, and it adds no redundant information about parameters.

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 'Personal records across activity types' clearly states a retrieval action (implicit) and a resource (personal records) with scope (across activity types). It distinguishes from siblings like garmin_whoami or garmin_last_activity by focusing on records, but it lacks detail on what exactly constitutes 'records' (e.g., best times, distances), so it's clear but not fully specific.

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?

There is no guidance on when to use this tool versus alternatives like garmin_activities or garmin_activity_splits. The description does not mention conditions, exclusions, or alternative tools, leaving the agent to infer based on the name alone. This is a significant gap for a tool with 34 siblings.

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