Fitbit Daily Sleep

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

Annotations already declare readOnlyHint and idempotentHint, so the safety profile is clear. Description adds value with auth requirement ('Requires sleep scope') and disclaimer ('Not medical advice'), but lacks details on behavior like data freshness or error handling.

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?

One sentence plus two short phrases, front-loaded with the key action. No wasted words. Ideal conciseness.

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?

Description is minimal. Does not explain output, handling of privacy_mode or response_format, or how data might change over time (openWorldHint). With an output schema present, return values are partially covered, but more context would help agents use the tool effectively.

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 covers 2 of 3 parameters with descriptions (67% coverage), so baseline is 3. The tool description itself does not add parameter meaning beyond the schema, but the schema descriptions are adequate.

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?

Clearly states verb 'Get' and resource 'sleep logs and stages for a date'. Specific and unambiguous. Does not explicitly differentiate from sibling tool fitbit_list_sleep, but the scope (single date vs. list) is implied.

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?

Mentions required 'sleep scope' but provides no guidance on when to use this tool versus alternatives like fitbit_list_sleep for multiple dates or other fitbit tools. No when-not advice.

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