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

With no annotations provided, the description must carry the full behavioral burden. It does disclose one key behavior: 'Body discarded,' indicating the response excludes content. However, it omits other relevant details such as authentication requirements, rate limits, or the exact status code range returned. The mismatch between the narrow description and the broad schema (9 unrelated params) also creates behavioral ambiguity.

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 sentence, front-loading the key action and scope. It is efficient with zero wasted words. However, its brevity borders on under-specification given the complexity of the 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?

This tool has 9 parameters, no output schema, and no annotations, yet the description provides only a minimal statement about HTTP status. It fails to explain the purpose of the other parameters, the expected output format, or how this tool relates to siblings. An agent would be underinformed about how to use it correctly, making this definition inadequate for its complexity.

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%, with each parameter having a descriptive comment. The tool description adds no extra meaning to these parameters; it only mentions the 'library docs URL' context, which doesn't clarify which parameter is relevant for the HTTP status check. Given the high schema coverage, the baseline of 3 is appropriate, but the description fails to bridge the gap between the stated purpose and the heterogeneous 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 states a specific verb and resource: 'HTTP status for a public library docs URL.' This clearly identifies the tool's core action and distinguishes it from generic fetch tools. However, it doesn't explicitly differentiate from siblings like fetch-status or web-fetch, which also deal with URL status/content, leaving some ambiguity about when to prefer this over them.

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 alternatives. It does not mention any exclusions, prerequisites, or sibling tools. An agent would have no indication whether to use this or fetch-status for a generic URL check.

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