get_sleep_data

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

Annotations already declare readOnlyHint=true, and the description adds value by detailing the return payload (sleep stage breakdown and heart rate) and the data source distinction. It goes beyond the annotation by explaining what data is returned and the API context, though it doesn't disclose rate limits or auth requirements.

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 concise sentences front-load the core purpose, followed by a useful note about the API source and return data. No unnecessary words or repetition of schema details.

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 tool with one optional parameter and an output schema, the description explains the return data (per-night breakdown, heart rate) and the API origin. It doesn't mention auth prerequisites, but sibling tools like authenticate_coros_mobile and check_coros_auth fill that gap. The output schema handles return structure, so completeness is adequate.

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 input schema has 100% description coverage for the single 'weeks' parameter, so the description doesn't need to add much. It mentions 'configurable time range' but doesn't elaborate on the weeks parameter beyond the schema. Baseline of 3 is appropriate given high schema coverage.

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 uses a specific verb ('Fetch') and resource ('nightly sleep data from Coros'), clearly distinguishing this tool from siblings like get_daily_metrics and list_activities. It also specifies the configurable time range, which adds scope clarity.

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 clearly implies it is the tool for sleep data from Coros and notes the API source (apieu.coros.com), which helps differentiate from Training Hub web API tools. However, it does not explicitly name alternatives or state when not to use this tool, so it falls short of a 5.

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