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

With no annotations provided, the description carries the burden of behavioral disclosure. It accurately implies a non-mutating parse operation, but it does not disclose that the many other schema parameters are ignored, nor how malformed or non-GitHub URLs are handled.

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?

One sentence, no filler, and the core function is front-loaded. Every word contributes.

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 description is minimally viable for a simple parser, but with 9 parameters, no output schema, and no annotations, it leaves ambiguity about the return shape and the irrelevance of the other parameters. A sentence noting that only `url` is used would complete it.

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% and each parameter is individually described. The tool description adds value by identifying that `url` is the meaningful parameter and that the output is owner and repo, which the schema's generic 'HTTPS URL to normalize or cite' does not convey.

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', identifies the resource ('owner and repo') and the input domain ('a GitHub URL'). This distinguishes it from sibling tools like normalize-url, domain-shape, and jira-key-shape without needing to inspect schemas.

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 phrase 'from a GitHub URL' gives clear context for when to use the tool, and the contrast with siblings is implicit. It stops short of explicitly naming alternatives or exclusions, so it loses the top score.

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