icu_get_activity_details

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

Annotations already declare readOnlyHint, destructiveHint, idempotentHint, and openWorldHint. The description adds that it returns a single JSON blob with top-level metrics, which is additional behavioral context but doesn't contradict annotations. It doesn't disclose potential limitations like rate limits or authorization, but the safety profile is already well-covered.

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 extremely concise, consisting of three sentences. The first sentence defines the tool's purpose, the second gives example use cases, and the third points to alternatives. Every sentence adds value and nothing is extraneous.

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?

The tool has one simple parameter and an output schema exists. The description explains what the output contains (headline summary with top-level metrics). Given the low complexity, this description is fully complete for an agent to select and invoke the tool correctly.

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 one parameter (activity_id) with description 'Activity ID to fetch'. Schema description coverage is 100%, so the baseline is 3. The description does not add further meaning beyond the schema's own description, so it stays at 3.

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 it fetches the headline SUMMARY of one activity, listing specific metrics like name, sport, date, distance, duration, training load, weather, and all top-level metrics. It also distinguishes between this tool and its siblings icu_get_activity_intervals and icu_get_activity_streams.

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 explicitly provides use cases (e.g., 'how was my ride?', 'tell me about activity X') and tells when not to use it: for lap-by-lap or per-interval breakdown use icu_get_activity_intervals, for second-by-second time-series use icu_get_activity_streams.

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