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

With no annotations, the description bears the burden of disclosing behavior. It reveals that the tool performs a public fetch and limits output to group counts, but it fails to disclose that the 9 schema parameters are largely unrelated to robots.txt, which parameter targets the robots URL, or error/rate-limit behavior. The mismatch between description and schema further undermines transparency.

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 with no fluff, but it is under-sized for the tool's complexity and leaves out critical invocation details. It is front-loaded but not sufficiently informative.

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 tool with 9 parameters, no annotations, no output schema, and a schema that doesn't align with the stated purpose, this one-line description is severely incomplete. It doesn't explain which parameter is the robots.txt URL, what group counts are, what the output shape is, or error behavior. This is below the minimum viable 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?

Schema description coverage is 100%, so the baseline is 3, but the description adds no parameter meaning and the schema itself is generic (e.g., 'HTTPS URL to normalize or cite') with no mention of robots.txt. The description never connects any parameter to the tool's actual operation, making correct invocation impossible.

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 states a specific action on a specific resource: fetching a public robots.txt and returning group counts only. This distinguishes it from sibling tools like web-fetch or domain-shape, which target other resources. However, it doesn't define what 'groups' means or name any alternative.

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?

There is no guidance on when to choose this tool over siblings such as web-fetch or normalize-url. No exclusions, conditions, or candidate scenarios are mentioned, leaving the agent to infer usage.

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