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, but it only says 'Parse owner and repo'. It does not describe what happens with invalid or non-GitHub URLs, what the output shape is, or why the schema contains many unrelated fields like city, feed, host, and zone. The presence of those unrelated fields makes the behavior even more opaque.

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 one short, front-loaded sentence with no filler. It earns its place by stating the core action clearly, and the conciseness is appropriate even if other dimensions suffer from under-specification.

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 has nine optional parameters, no annotations, no output schema, and a description that does not explain return values, error behavior, or the role of the url parameter relative to the other fields. This is far too little context for an agent to invoke the tool confidently and interpret the result.

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%, so the baseline is 3 even without parameter information in the description. The description adds a hint that 'url' should be a GitHub URL, but the schema's own 'url' description says 'HTTPS URL to normalize or cite', which creates ambiguity. It does not clarify which of the nine optional parameters are actually relevant for parsing owner and repo.

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 operation, 'Parse owner and repo', on a specific resource, 'a GitHub URL'. This makes the core purpose clear and differentiates it from sibling URL tools like normalize-url or browser-url-ok, though it does not explicitly name those alternatives.

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 use this tool versus the many sibling URL/shape tools. The description provides no context, exclusions, or alternative conditions. Usage must be inferred entirely from the tool name and the single purpose sentence.

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