Fitbit Activity Logs

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is clear. The description adds that the tool supports cursor, pagination, and privacy modes, which aligns with schema parameters. It does not contradict annotations and provides some behavioral context, but does not disclose additional traits like rate limits or data freshness.

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?

The description is extremely concise: two sentences that immediately convey the core purpose and key capabilities. Every sentence adds value, and the most important information (the action) is front-loaded. No redundant or vague phrases.

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 9 parameters and an output schema, the description is minimal but covers the main features. However, it omits important context such as default sorting order, behavior when both 'after' and 'before' are provided (schema says mutually exclusive, but description should confirm), or pagination limits. The presence of an output schema reduces the need to describe return values, but some behavioral details are missing.

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 89%, so the schema already documents parameters well. The description mentions cursor, pagination, and privacy modes but does not add new meaning beyond what is in the schema. For example, it does not explain the difference between 'after' and 'before' or the effect of 'privacy_mode' beyond the schema's own descriptions. Baseline of 3 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?

The description clearly states the verb 'List' and the resource 'Fitbit activity logs', making the purpose obvious. It also mentions supported features like cursor, pagination, and privacy modes. However, it does not explicitly differentiate from sibling tools like fitbit_get_activity or fitbit_get_activity_day, though the name implies a listing action.

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 notes the required scope ('Requires activity scope') but provides no guidance on when to use this tool versus alternatives like fitbit_get_activity_day or fitbit_list_sleep. There is no mention of scenarios where this tool is inappropriate or when another tool should be preferred.

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