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

With no annotations, the description carries the full burden of disclosing behavior, but it only says 'fetch' and 'return group counts'. It does not clarify that it is read-only, how it handles missing/invalid robots.txt files, or that the schema contains many irrelevant-looking parameters.

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, tightly worded sentence with no filler or redundant details. It uses a clear action-object-result structure.

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?

In the absence of annotations and an output schema, this one-sentence description is not enough to call the tool correctly. The relationship between the 9 optional parameters and the described robots.txt fetch operation is completely unexplained.

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?

Although the schema has 100% parameter description coverage, those descriptions (e.g., 'Git ref name; discarded after the shape check', 'HTTPS URL to normalize or cite') do not align with the stated purpose of inspecting robots.txt. The tool description adds no clarification about which parameter actually supplies the robots.txt URL.

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 clear action (fetch), a specific resource (public robots.txt), and a constrained output (group counts only). It is more specific than generic web-fetch siblings, though 'group counts' is somewhat ambiguous.

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 over alternatives such as web-fetch or normalize-url. There is no mention of appropriate input selection or any conditions that favor this tool.

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