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 explain what happens for invalid URLs, whether it also validates shape, what the return format is, or why many schema parameters (city, feed, json, path, query) appear to be unrelated. The schema descriptions actually reveal more behavioral context than the tool description.

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, front-loaded sentence with no filler words. It is concise and immediately readable, though its brevity comes at the cost of omitted behavioral and usage context.

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, no annotations, and many sibling shape tools, a one-sentence description is not complete enough. The agent cannot determine the output shape, error behavior, or why most schema parameters exist, so the description is inadequate for reliable tool selection and 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 description coverage is 100%, so the structured schema already documents all 9 parameters. The description adds minimal mapping value by relating the 'GitHub URL' to the url parameter, but it does not compensate for the apparent mismatch between the description and the many unrelated parameters.

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 ('Parse') and identifies the exact resource ('owner and repo from a GitHub URL'). This distinguishes it from sibling tools like domain-shape or jira-key-shape by naming GitHub URLs, though it does not mention shape validation/checking implied by the tool name.

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?

No guidance is given about when to use this tool versus alternatives such as normalize-url, browser-url-ok, or figma-url-shape. There are no usage conditions, exclusions, or references to sibling tools.

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