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

With no annotations, the description must disclose behavior, but it only says it parses owner and repo. It fails to explain that the tool likely ignores most of the 9 parameters, what happens with invalid URLs, the output format, or any side effects. This is a significant gap given the tool's parameter complexity.

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 that is front-loaded, but it is under-specified for a tool with 9 parameters. While brevity is good, the lack of essential detail makes it less effective than it could be.

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?

Given the tool has 9 parameters and no output schema, the description is severely incomplete. It does not specify the expected input format, the output structure (owner and repo as separate fields?), error handling, or which parameters are ignored. An agent would have difficulty calling this tool correctly based on the description alone.

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 schema description coverage is 100%, the tool description adds minimal value beyond the schema. It implies 'url' is the key input, but the schema describes it as a generic 'HTTPS URL to normalize or cite' without linking it to GitHub. The description does not clarify which of the 9 parameters are actually used or how they relate to the parsing task.

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 a specific action ('Parse owner and repo') and a resource ('GitHub URL'), which distinguishes it from sibling tools like domain-shape or figma-url-shape. However, it doesn't explicitly mention that only the 'url' parameter is relevant, leaving a slight ambiguity about the tool's scope.

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 implies this tool is for GitHub URLs, and the sibling names suggest alternatives for other URL types. But there is no explicit guidance on when to use this vs. other shape-checking tools, nor any mention of when not to use it.

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