Fitbit Sleep Logs

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

Annotations already indicate read-only, non-destructive, idempotent, open-world. The description adds 'Not medical advice' and notes privacy modes, providing additional behavioral context without contradiction.

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?

Three sentences front-loaded with purpose. No wasted words. Clear and efficient.

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 8 parameters, no required, and an output schema, the description is sufficient. It covers key aspects like pagination and privacy. The output schema handles return values, so no need to explain them here.

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 88%, so baseline is 3. The description mentions 'before/after cursor, pagination and privacy modes,' but the schema already describes each parameter. The description adds minimal new semantics beyond grouping.

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 verb and resource: 'List Fitbit sleep logs.' It is distinct from sibling tools like fitbit_list_activities and fitbit_list_devices, and the resource 'sleep logs' is specific.

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 mentions supports for cursors, pagination, privacy modes, and required scope, providing good context. However, it does not explicitly state when not to use this tool or compare it to alternatives like fitbit_get_sleep_day for a single day's data.

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