get_performance_conditionFetch the performance condition score for a given date, using Garmin activity data to measure training performance.
Get the performance condition score for a date. Garmin records this per activity rather than daily, so it is usually only available through get_activity_details.
| Name | Required | Description | Default |
|---|---|---|---|
| date | Yes | Date in YYYY-MM-DD format (required) |
Changes observed during successful MCP inspections.
v4.3.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations mark readOnlyHint=true and openWorldHint=true, but the description adds the critical behavioral constraint that performance condition is per-activity not daily, so the tool may return no value for a given date. This is valuable beyond annotations, helping the agent anticipate incomplete data.
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 concise and front-loaded with the main purpose, then provides useful context in a follow-up sentence. No fluff.
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?
Given the tool has one parameter, full schema coverage, and annotations, the description covers the key caveat about data availability. It could mention that the result may be null or unavailable, but the caveat effectively conveys this. Slightly lacking because it doesn't hint at what the score means or any units.
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 sole parameter 'date' is fully described in the schema with format and pattern. The description doesn't add extra semantics but the schema coverage is 100%, so baseline 3 is appropriate.
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 the tool returns a performance condition score for a date. It also notes a key constraint: Garmin records this per activity rather than daily, so it's usually only available through get_activity_details. This differentiates it from sibling get_* tools that return other metric types.
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 says the metric is usually only available through get_activity_details, implying users should prefer that sibling tool for per-activity data. This provides clear context for when this tool may not be useful, though it doesn't state absolute exclusions or when to use it directly.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.