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

There are no annotations, so the description carries the full burden of behavioral disclosure. It implies a read-only lookup but says nothing about URL expectations, external network dependence, rate limits, failure behavior, or what a 'page' means in the Common Crawl context.

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 short and easy to scan, but it is repetitive ('Common Crawl' appears twice) and front-loads a generic label rather than meaningful detail. It is concise but under-structured.

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?

Even though an output schema exists, the description is too thin for a one-parameter tool with no annotations. It leaves the meaning of q, the expected input format, and the relationship to sibling Common Crawl tools completely unexplained.

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?

The sole parameter q has zero documentation in the schema, and the description never names or explains it. The phrase 'capture index lookup' weakly suggests q is the page/URL to look up, but this is not explicit enough to construct a correct call.

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 identifies a resource (Common Crawl capture index) and a generic action (lookup), so it is clear this is some kind of lookup tool. However, it is vague about what exactly is returned and does not distinguish it from closely related siblings such as commoncrawl, cdxwayback, or wayback.

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?

No guidance is given about when to use this tool versus alternatives. Sibling tools like commoncrawl, cdxwayback, and wayback overlap heavily in domain, and the description offers no decision criteria or exclusions.

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