get_fitness

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

No annotations are provided, so the description carries full burden. It discloses that some metrics are date-agnostic and others require a date range, which is useful behavioral trait. However, it lacks details on output format, authentication needs, or potential errors.

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 a single sentence that front-loads the main purpose and efficiently conveys parameter usage. No redundant words; every phrase adds value.

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?

With no output schema, the description omits return format details. However, it covers the essential aspects: available metrics, how dates affect them, and parameter defaults. For a tool with no required parameters, this is nearly complete, though a brief note on output structure would help.

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 coverage is 100%, but the description adds meaning by grouping metrics into two categories (date-agnostic vs. date-range) and clarifying default values for dates and metrics. This goes beyond the schema's parameter descriptions.

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 states the tool returns 'Fitness/performance metrics' with a specific list of metric names, distinguishing between date-agnostic and date-range metrics. This clearly identifies the resource and scope, differentiating it from sibling tools like get_training or get_daily_health.

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 how to select metrics via the `metrics` parameter and clarifies which metrics need date parameters. However, it does not explicitly state when to prefer this tool over siblings, nor does it provide when-not-to-use guidance.

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