Assign a gear item to a Garmin activity using its gear UUID and activity ID to track equipment usage on the correct workout.
on 404 re-raises as GarminConnectionError ("gear not found (likely retired/removed)")
| Name | Required | Description | Default |
|---|---|---|---|
| gearUUID | Yes | ||
| activityId | Yes | Numeric id |
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=false, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds genuine behavioral value by disclosing the 404 error semantics and the GarminConnectionError re-raise, which an agent cannot learn from the schema, though it says nothing about success behavior, permissions, or idempotency.
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?
It is short, but that brevity comes from under-specification rather than economy. It is also a sentence fragment and is not front-loaded with purpose, so a reader gets error trivia before knowing what the tool does.
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 write tool with no output schema and an unambiguous 2-parameter signature, the description omits the core purpose, success behavior, and prerequisites. The single error-handling note is useful but leaves the definition largely incomplete.
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 only 50%: activityId is documented as 'Numeric id' but gearUUID has no schema description, and the description provides no clarification of either parameter's format or constraints. With half the parameters undocumented, the description fails to compensate.
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 never states what the tool does — it only documents a 404 failure mode. Only the tool name implies that gear gets attached to an activity; the text itself carries no verb+resource purpose statement.
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, no prerequisites (e.g., gear must exist and not be retired), and no mention of the obvious alternative remove_gear_from_activity or which activity/gear combos are valid.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.