fitbit_get_devices

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

No annotations provided, so description carries full burden. It notes 'Live-only (no caching)', which is a key behavioral trait. However, it omits potential error conditions or output format nuances, leaving some gaps in transparency.

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 concise sentences with no redundancy. First sentence states purpose, second adds behavioral and usage context, third lists return fields. Every sentence is informative and earns its place.

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 zero parameters and presence of an output schema, the description is complete: it lists returned fields, explains use cases, and notes live-only behavior. No additional information is needed for a read-only device listing tool.

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?

No parameters exist in the schema, so baseline is 4. The description does not need to add parameter info; it correctly focuses on the tool's action and output.

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 'List' and the resource 'paired Fitbit devices' with specific attributes (battery level, last sync time). It distinguishes itself from sibling tools like fitbit_get_activity which target different data.

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 explains when to use: for monitoring tracker health, knowing which device produced data, and spotting sync gaps. While it doesn't explicitly state when not to use, the sibling tools are distinct, so usage context is clear.

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