Fitbit Weight Logs

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

Annotations already declare it's read-only, idempotent, and non-destructive. The description adds the requirement for 'weight scope' and a disclaimer about medical advice, which is useful behavioral context beyond the structured annotations.

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, no wasted words. The first sentence front-loads the purpose. Every word contributes meaning.

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 presence of an output schema (not shown but indicated) and informative annotations, the description adequately covers the tool's behavior. It adds scope requirement and disclaimer, which are important for a health data 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?

Schema description coverage is 67%, so the schema already explains the 'date' and 'privacy_mode' parameters well. The description does not add extra meaning beyond what the schema provides. Baseline score is appropriate.

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 the tool retrieves weight logs for a date. The verb 'Get' and resource 'weight logs' are specific. Sibling tools like fitbit_get_activity_day and fitbit_get_sleep_day are distinct, so no confusion.

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?

Provides essential context: requires weight scope (authorization) and disclaimer that it's not medical advice. Does not explicitly state when not to use or list alternatives, but the sibling set makes the purpose clear enough.

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