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

No annotations are provided, so the description carries full responsibility. It states the core action but discloses no behavioral traits: no mention of error handling on invalid URLs, no mention of return format, no mention that the other parameters are ignored. The description is too terse to reveal how the tool behaves beyond its primary intent.

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?

A single, precise sentence with no redundancy. It is front-loaded with the action and resource, and every word earns its place. This is an exemplar of conciseness.

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 output schema, and no annotations, the description is incomplete. It does not explain the return value, how the URL is parsed, or why the other parameters exist. An agent cannot fully anticipate behavior or errors, especially given the unusual mix of parameters.

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 schema describes all 9 parameters, and the description clarifies the purpose of the 'url' parameter by linking it to owner/repo extraction. However, the description ignores the 8 other parameters, which the schema marks as discarded or irrelevant. This leaves ambiguity about whether they are used, though the schema coverage is 100% and the description adds value for the primary parameter.

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 verb and resource: 'Parse owner and repo from a GitHub URL.' This clearly differentiates it from sibling shape tools like domain-shape or jira-key-shape by naming the exact input and output. It is unambiguous and actionable.

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 versus alternatives. It does not mention that it is for extracting owner/repo from GitHub URLs only, nor does it contrast with similar tools like normalize-url or browser-url-ok. An agent would have to infer usage from the name alone.

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