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

The description indicates a read-only fetch operation but does not disclose any potential side effects, caching behavior, or error conditions.

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, but the input schema includes many irrelevant parameters that could be trimmed for clarity.

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?

The tool lacks an output schema and critical usage context, such as which parameter specifies the target URL and what the returned group counts look like, leaving the agent uncertain about how to call it.

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 9 optional parameters have descriptions that are mismatched with the tool's purpose (e.g., 'Git ref name', 'City name for weather') and do not clarify which parameter is used for the robots.txt URL, making it impossible to know how to correctly invoke the tool.

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 fetches a public robots.txt and returns group counts, which is specific and distinct from sibling tools like web-fetch or fetch-status.

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 mention of when to use this tool over alternatives such as web-fetch or fetch-status, nor any conditions that would favor this tool.

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