What this server covers

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

The annotations already convey read-only, idempotent, and open-world behavior, so the description's burden is low. It adds value by specifying which coverage dimensions the tool reports and explicitly mentioning that it also states what is not covered, which helps set expectations about the response.

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 short sentences carry the full meaning: the first states what the tool lists, the second states precisely when to call it. There is no filler, and the key scoping guidance is front-loaded.

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 coverage tool with rich annotations and an output schema, the description is complete. It tells the agent what to expect from the tool and when to use it, leaving no meaningful gap for selection or invocation.

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, so the description cannot add parameter-level meaning. The baseline for parameterless tools is 4, and the description correctly focuses on what information the tool returns instead of inputs.

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 names a specific verb ('List') and a concrete resource: the server's coverage across topics, geography, sources, and freshness. It also explicitly states what the tool does not cover, which clearly differentiates it from the domain-specific sibling tools.

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 gives an explicit condition for use: 'Call this only when unsure whether a question is in scope.' This tells the agent exactly when to invoke this meta-coverage tool and implies that confident, in-scope questions should go to the relevant sibling tools instead.

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