garmin_activity_analysis

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds one valuable behavioral fact beyond that — the tool depends on an original FIT file and will fail for manually created activities — but says nothing about cost, latency, or result size for a potentially heavy per-record analysis.

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?

Two sentences, no filler, and the differentiating claim is front-loaded before the caveat. Every clause carries information the agent can act on.

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 read-only single-activity analysis tool with no output schema, the definition covers what it does and when it fails, which is the minimum. It leaves unclear what the return payload looks like in aggregate and how it relates to sibling tools that surface overlapping data, so an agent could still pick this redundantly.

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 coverage is 50%: the include enum is exhaustively self-documented, while activity_id is bare. The description adds nothing to either parameter, but since the harder parameter is fully documented in the schema, it does not need to compensate heavily. Baseline 3 applies.

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?

States a specific resource (the activity's original FIT file) and positions itself comparatively: 'deeper analysis ... beyond what Garmin Connect shows.' That contrast implicitly separates it from the basic garmin_activity sibling, though it never names an alternative and the verb 'analysis' stays generic until the schema's include enum supplies the actual outputs.

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?

Implies when to reach for it (deeper metrics than Garmin Connect exposes) and supplies one genuine exclusion: manual activities have no FIT file. It gives no positive routing against siblings like garmin_activity, garmin_power_curve, or garmin_fit_messages, so the agent must infer which tool to pick for a given question.

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