Fitbit Quickstart

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

Discloses adaptive behavior based on current state (env vars, token), which adds value beyond annotations that already indicate read-only, idempotent, non-destructive nature.

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 sentences with zero wasted words; purpose is front-loaded and efficiently conveys key points.

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 the tool's simplicity (one optional parameter, no output schema) and good annotations, the description fully covers when and why to use it.

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?

Only parameter (response_format) is not described in the description; schema coverage is 0% and description does not compensate for this lack of parameter documentation.

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 it's a personalized 3-step setup walkthrough for connecting Fitbit, specific verb+resource and distinguishes from data retrieval siblings.

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?

Explicitly says 'Call this first when the user asks how do I connect Fitbit?' providing clear context, though no explicit when-not or alternatives are stated; sibling differentiation implies alternatives.

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