Scan a URL

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

The description goes beyond annotations, detailing that the tool returns an id immediately, never a compliance score, and explains the recording behavior. No contradiction with annotations.

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 concise with three sentences, each adding value: purpose, behavior, and important limitation. No fluff.

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?

Given the simplicity (1 param, output schema exists), the description fully covers what the tool does, how results are obtained, and the caveat about compliance scores. No gaps.

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%, so baseline 3. The description adds 'Pass the URL and nothing else,' which slightly reinforces the single parameter but does not add significant new semantic information beyond the schema.

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 identifies the tool as scanning a single http(s) URL for accessibility problems using axe-core, distinguishing it from sibling tools like get_scan (polling) and check_pdf (PDF scanning).

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 explains when to use (scan a URL), how results are obtained (poll with get_scan), and notes the recording behavior for registered sites. It does not explicitly mention when not to use but provides sufficient context.

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