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

With no annotations provided, the description carries the full burden of behavioral disclosure. It says 'Parse owner and repo from a GitHub URL' but the input schema includes 9 parameters, most of which (city, feed, host, json, path, zone, query) are completely unrelated to the stated purpose. This creates confusion about what the tool actually does with those inputs and whether it is a generic shape validator. The description does not disclose that it may handle other input types, nor does it explain the discarded parameters mentioned in the schema. This is a serious transparency gap that could mislead an agent.

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 extremely concise (one phrase) and front-loaded with the core action. However, it lacks structure and explanatory detail, failing to mention the presence of unrelated parameters or the tool's broader behavior. While brevity is a virtue, it is under-specified for a tool with 9 parameters and no output schema, so it earns a mid-range score.

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 annotations, and no output schema, the description is far from complete. It does not explain return values, error behavior, or the purpose of the many unrelated parameters. The description is insufficient to guide an agent on how to call the tool correctly, especially since it appears to be part of a family of similar 'shape' tools but is not distinguished adequately.

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 description coverage is 100%, so each parameter is documented in the schema. The tool description adds no additional meaning about parameters, but the baseline of 3 applies because the schema already provides adequate descriptions. The description's silence on parameters does not reduce clarity, but it also does not enhance it beyond what the schema offers.

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 ('Parse') and a clear resource ('owner and repo from a GitHub URL'). It is unambiguous about the core function. However, it does not explicitly differentiate from sibling shape tools like domain-shape or figma-url-shape, relying on the GitHub-specific resource to make the distinction implicit.

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 its siblings. There is no mention of alternatives, conditions, or exclusions. An agent would have to infer from the name and the phrase 'GitHub URL' that this is the tool for GitHub repo extraction, but no explicit routing is given, especially given the large number of sibling shape tools.

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