Retrieve Garmin gear statistics by UUID. Returns an empty object on 404 instead of throwing an error.
GETs /gear-service/gear/stats/{gearUUID}; gearUUID validated via validateUuid (hex, hyphens optional); returns {} on a 404 instead of throwing; other errors re-raised
| Name | Required | Description | Default |
|---|---|---|---|
| gearUUID | Yes |
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and openWorldHint=true, but the description adds non-obvious error-handling behavior: a 404 yields an empty object rather than throwing, while other errors propagate. That is exactly the kind of trait an agent needs and cannot get from the annotations.
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?
A single dense sentence with no filler, though it is front-loaded with the raw HTTP endpoint path, which is less useful to an agent than the semantic purpose would be. Nothing is redundant.
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 should convey what 'stats' contains, and it does not — it only covers the 404 case. It is adequate for invocation (validation rules, error behavior) but leaves the return shape opaque.
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?
With only one parameter and 0% schema description coverage, the description must carry the burden, and it does: gearUUID is validated with validateUuid and accepts hex with optional hyphens. That adds real syntactic meaning beyond the bare 'string' in the schema.
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 names a specific verb ('GETs') and resource (gear stats for a given gearUUID), so an agent can tell this fetches aggregate stats rather than the gear item itself. However it never differentiates from siblings like get_gear, get_gear_activities, or get_gear_defaults, so the boundary with those tools must be inferred.
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 call this versus get_gear (gear metadata) or get_gear_activities (per-activity gear usage). The agent is left to infer that 'stats' is a distinct payload from the sibling tools'.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.