Probe an HTTP endpoint

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

Annotations declare read-only, idempotent, non-destructive and open-world, but the description adds real value beyond them: bounded redirects, bounded body size, and that only metadata is returned. It does not mention auth requirements or rate limits, but the bounding constraints are meaningful behavioral disclosure.

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, front-loaded with the verb and resource, with the two most consequential constraints (redirects, body size) and the return-shape caveat packed in tightly. No waste.

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?

An output schema exists, so return values needn't be detailed, and annotations cover the safety profile. The main gap is parameter documentation, which the description only partially addresses. Given the structured fields available, the description is nearly complete.

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 0%, so the description must compensate. It partially does: 'bounded redirects' explains follow_redirects, and 'not body data' implies HEAD/GET metadata behavior, but url format and method semantics are left undocumented. Partial compensation, not full coverage.

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?

States a specific verb (Fetch) and resource (one authorized URL) plus the distinctive behavior (returns metadata, not body data). Clear enough to distinguish from web_crawler and headers_analysis, though it does not explicitly name a sibling like batch_http_probe.

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 word 'authorized' implies a scoped/safety context and 'one URL' hints at the batch alternative, but no explicit when-to-use or when-not-to-use guidance is given and no sibling is named. An agent must infer the routing.

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