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

With no annotations, the description carries the full burden. 'Parse' suggests a local, non-mutating operation and the output is implied, but the description does not mention invalid URL handling, whether the tool fetches anything, or what the return shape looks like. It is adequate for a simple parse tool but not fully transparent.

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 wasted words. It states the action and the expected input domain clearly, which is ideal for a simple parsing tool.

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 simple parse operation, the description is reasonably complete, but the absence of an output schema and annotations leaves the exact return format unstated. The large set of optional parameters also creates ambiguity about what the tool actually consumes, so a bit more contextual detail would help.

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 baseline is 3. The description adds meaning by clarifying that the URL should be a GitHub URL for owner/repo extraction, but it does not clarify the purpose of the other eight parameters or which ones are relevant to this tool.

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 a specific resource ('owner and repo from a GitHub URL'), which clearly communicates the tool's function. It also distinguishes this tool from sibling URL/shape tools like figma-url-shape and jira-key-shape without needing to open the schema.

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 usage: use this tool when you need to extract owner and repo from a GitHub URL. However, it gives no explicit guidance about when not to use it or which sibling tool should be used instead for related tasks such as URL validation or normalization.

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