api_usage

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

With no annotations, the description must carry the behavioral burden. The word 'View' clearly indicates a read-only operation, which is useful. However, it does not describe what statistics are included, how they are aggregated, or the response shape, so behavioral disclosure is minimal beyond indicating safety.

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, front-loaded sentence with no filler, redundancy, or irrelevant caveats. It earns its place and is appropriately sized for a zero-parameter tool.

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?

For a parameterless read-only tool, the description is largely complete enough for selection and invocation. However, there is no output schema and no detail about what 'usage statistics' includes (e.g., call counts, quotas, time window), leaving moderate ambiguity about the expected return value.

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?

The tool has zero parameters and an empty input schema, so the description cannot add parameter-level meaning. Per rubric, 0 params earns a baseline 4 because there is no parameter ambiguity for an agent to resolve.

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 uses a specific verb ('View') and a clear resource ('current API usage statistics'), which is distinct from the product-focused sibling tools. An agent can immediately identify this as the monitoring/usage tool without needing to inspect other definitions.

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 phrasing 'current API usage statistics' establishes a clear context: use this when you need current usage information. There are no plausible alternatives among the product-lookup siblings, so explicit exclusionary guidance is not necessary, but it stops short of stating precise when-to-use conditions.

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