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

There are no annotations, so the description must disclose behavioral traits. It states what the tool checks but does not mention side effects, read-only nature, or the format of the response. For a tool that appears to be a simple ping, these details are important for an agent to know what to expect.

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 concise sentence that directly states the purpose. It is front-loaded with the verb and object, and contains no filler or redundant information.

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 and lack of parameters, the description is adequate but has gaps. It does not explain what the output or return value will be (e.g., a boolean, a status object). Since there is no output schema, the description should provide this information to be fully complete.

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 the input schema is empty. With 0 parameters, the baseline for parameter semantics is 4. The description does not need to explain parameters, and it correctly avoids adding unnecessary detail.

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 function: 'Prüft, ob Faxversand verfügbar ist und ob er bezahlt (Stripe) läuft' (checks if fax sending is available and if it is running via Stripe). This specific verb 'prüft' and the resource 'Faxversand' clearly differentiate it from sibling tools like fax_status (which likely checks a specific fax job) or fax_quote (which provides pricing).

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 provides no context on when to use this tool versus alternatives. It does not mention any prerequisites, exclusions, or alternative tools. The user is left to infer that it is a health check, but there is no explicit guidance on when to invoke it.

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