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

Annotations indicate readOnlyHint=true, and the description reinforces this by stating it reports information without modifying data. It adds useful context about what it diagnoses (permission vs. data absence), complementing the annotations without contradicting them.

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 concise and informative, using two sentences to convey purpose and usage guidance without unnecessary verbosity. It is well-structured and immediately relevant.

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 (no parameters) and the presence of an output schema, the description sufficiently covers its purpose, usage, and diagnostic value. It is complete enough for an agent to invoke it appropriately.

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?

Since there are no parameters, the schema coverage is 100%, and the baseline is 4. The description effectively explains what the output indicates, adding value beyond the empty schema.

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 tool's purpose: reporting the access tier, available tools, and request budget. It distinguishes itself by explaining it helps differentiate between permission issues and data availability, which is distinct from sibling tools that fetch content.

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 advises using this tool first when a Trend tool is refused or returns unexpected results. It implies a diagnostic role but does not explicitly state when not to use it or mention specific alternatives, hence a slight deduction.

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