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

With no annotations provided, the description must disclose behavioral traits on its own. It mentions that it returns only group counts, which implies it does not return full content, but it omits critical details such as network access requirements, potential failures, or how the many parameters are used. Most parameters are described in the schema as discarded, but the description does not mention this, leaving the agent unsure about side effects or inputs.

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, which is appropriately brief for the core action. However, it is under-specified: it omits essential context about which parameters matter and what the output looks like. Conciseness is fine, but the content is insufficient for effective use.

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 has 9 parameters, no output schema, and no annotations, the description is grossly incomplete. It does not explain which parameter is the robots.txt URL, what 'group counts' means, the output format, error handling, or how the other parameters are used or discarded. An agent cannot reliably call this tool correctly based on the provided description.

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?

While the schema covers 100% of parameters, the description adds no meaning beyond the schema. More importantly, the parameters are unrelated to the stated purpose—e.g., 'city' for a weather hint, 'json' to validate, 'zone' for timezone—none of which relate to fetching a robots.txt. The description does not clarify which parameter identifies the target URL, making the tool's interface confusing and requiring the agent to infer a connection that is not stated.

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 action (fetch a public robots.txt) and the result (return group counts only). It names a specific resource and operation, but does not differentiate it from siblings like web-fetch or fetch-status, which could also retrieve a robots.txt. The name and description align well, but the sibling distinction is missing.

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 guidance on when to use this tool instead of alternatives like web-fetch or fetch-status. It does not mention any conditions, prerequisites, or scenarios where this tool is preferred. The agent is left to infer usage from the name and description alone.

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