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

With no annotations, the description carries the transparency burden. It does disclose the return kind ('HTTP status') and the body handling ('Body discarded'), but it omits other behavioral details such as redirects, error handling, auth, rate limits, and behavior for non-library-docs URLs.

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 two short sentences with no filler. The core purpose is front-loaded and each sentence earns its place.

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 tool has 9 optional parameters and no output schema, yet the description doesn't say which parameter to pass or what output structure to expect. It also leaves the relationship between the 'public library docs URL' purpose and the many unrelated schema fields unexplained, so an agent must guess how to invoke it correctly.

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 schema already documents each parameter and the description adds no additional parameter-level meaning. Some schema entries explicitly say values are 'discarded after the shape check', which weakens their semantic value but does not create a contradiction.

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 operation ('HTTP status') and resource ('public library docs URL'), and adds the key body-discarded behavior. It is clear enough to distinguish the tool from generic fetch tools, though it doesn't explicitly contrast with siblings.

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 'Body discarded' implicitly tells an agent to use this tool when only the HTTP status is needed and not the response body. However, it doesn't name alternatives like fetch-status or web-fetch, and it gives no explicit when-to-use or when-not-to-use guidance.

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