Check whether today's Garmin metric values are normal for you by comparing them with personal mean and standard deviation bands over a trailing window.
Personal mean +/- sd band per metric over a trailing window (default 28 days; default metrics: resting_hr, hrv, sleep_score, skin_temp_dev_c, stress_avg, steps).
Use to judge whether today's value is normal for this user.
| Name | Required | Description | Default |
|---|---|---|---|
| metrics | No | ||
| window_days | No |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description bears full weight. It explains the computation (mean and sd) and default window/metrics, but omits details like return format, data freshness, or edge cases (e.g., insufficient 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: two sentences that front-load the core concept and purpose, with no redundant words.
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?
Although the tool is simple, the description lacks details on output format (e.g., structure of the band) and does not cover potential errors or data requirements. Without annotations or output schema, more completeness would be beneficial.
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 coverage is 0% with no parameter descriptions. The description compensates by listing default values for both parameters and specifying the default metrics list, adding significant meaning beyond 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 clearly states it computes mean +/- sd band per metric over a trailing window and is used to judge if today's value is normal for the user. It specifies default window and metrics, making the purpose unambiguous and distinct from siblings like 'anomalies'.
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 to use it for judging normality and references default parameters. However, it does not mention when not to use this tool or alternatives like 'query_metrics' or 'anomalies'.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.