Get activity details

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so the safety profile is covered. The description adds genuine behavioral scope: what the payload contains, that dive/multisport blocks appear conditionally, and that sample-level data is excluded. It doesn't cover failure modes for invalid/nonexistent IDs, which keeps it below 5.

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 dense sentences: the first front-loads the return contents, the second handles provenance and the sibling hand-off. Every clause carries information and nothing is repeated.

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?

With no output schema, the description does the work by enumerating returned sections and their units (distance m, duration s, speeds m/s), which is what an agent needs to decide whether this tool answers its question. The sibling routing closes the remaining gap.

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 100% and the single activityId parameter is fully typed and documented, so the baseline is 3. The description's note to source the ID from garmin_search_activities restates what the schema description already says, adding no new format or constraint information.

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 verb ('Get the full detail of one activity') plus the resource and enumerates exactly which fields come back (name, type, summary metrics, lap summaries, dive/multisport). It also distinguishes itself from two siblings by naming where the ID comes from and which tool to use for raw samples.

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?

Gives an explicit prerequisite ('Get the activityId from garmin_search_activities') and an explicit exclusion with the alternative ('Does not include per-second samples; use garmin_download_activity_file for the raw FIT data'). Both the when and the when-not are covered.

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