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

With no annotations, the description carries the full burden of behavioral disclosure. It does disclose that the tool performs a network fetch of a public resource and returns only aggregated counts, which is useful. However, it does not mention error behavior, whether the URL must be supplied via the 'url' parameter, or implications of fetching external content.

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 well-structured sentence that front-loads the core action and output constraint. Every word earns its place; there is no clutter or repetition of the tool name.

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?

Despite having four optional parameters and no output schema, the description does not specify which parameter is required for the fetch, what 'group counts' refers to in the returned data, or how failures are surfaced. An agent could guess, but the definition is not complete enough for reliable invocation.

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 coverage is 100%, but the schema descriptions are generic and not tailored to robots.txt: 'url' says 'normalize or cite', 'json' says 'validate', and 'zone' says 'IANA timezone name'. The tool description does not map any parameter to the fetch target, leaving the agent unsure whether to pass url, host, or something else.

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 uses a specific verb ('Fetch'), a precise resource ('public robots.txt'), and an explicit output scope ('group counts only'). This makes the tool's purpose immediately clear and distinguishes it from generic siblings like normalize-url or domain-shape.

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 gives no conditions for when to use inspect-robots instead of sibling tools, and it offers no exclusions or alternative recommendations. An agent is left to infer when fetching robots.txt is appropriate relative to the other listed tools.

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