verify_url

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

With no annotations, the description carries the transparency burden. It discloses the mechanics (DNS, optional HTTP HEAD) and speed (≈50ms), but it does not describe the return value, failure behavior (e.g., does an invalid URL throw or return a flag), or whether there are any side effects beyond the network checks.

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 compact two-sentence summary with no filler. It front-loads the purpose and immediately offers the most important usage direction, saving tokens while conveying the essential value.

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 is simple with one required parameter, but there is no output schema and the description does not specify what the result indicates (e.g., success/failure status) or how the agent should respond to an invalid URL. This is a significant gap for an agent to correctly interpret the tool's result.

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 covers all parameters at 100%, so the baseline is 3. The description mirrors the check_http behavior but does not add new meaning for individual parameters beyond what the schema states; it only contextualizes the timeout by comparing to the 30s navigation.

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 clearly states the tool's action: a fast pre-check for a URL, specifically performing DNS and optional HTTP HEAD, with the goal of catching typos and dead domains. It also explicitly frames it as a precursor to 'go', which distinguishes it from the navigating tool.

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 clear context: use this before 'go' to avoid a 30s navigation timeout. It implies the tool is for early validation, though it does not explicitly state when not to use it or name alternatives beyond 'go'.

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