audit_understandable

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

With no annotations, the description must disclose behavioral traits. It notes that the tool runs 6 axe rules and requires one input source. However, it does not mention whether the tool is read-only, authentication needs, error handling, or any side effects. The output schema exists but is not referenced. The description provides basic behavior but lacks thoroughness.

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 consists of two concise sentences. The first explains the tool's purpose, and the second gives input instructions. Each sentence adds value without redundancy. This is well-structured and front-loaded.

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 output schema exists, return values need not be detailed. However, the description omits the 'level' parameter, which is important for WCAG conformance levels. It also doesn't list the specific WCAG criteria covered. For a tool with 4 parameters and 0% schema coverage, the description should be more complete to avoid confusion.

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 0%, so the description must compensate. It correctly indicates that url, html, and session_id are mutually exclusive inputs. However, it does not explain the 'level' parameter (default AA) or its possible values (A, AA, AAA). Thus, it adds partial meaning but misses an important parameter.

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 that the tool audits the WCAG 'Understandable' principle by running 6 specific axe rules. This distinguishes it from sibling tools like audit_perceivable and audit_operable, which cover other principles. The verb 'audit' combined with the specific principle and rule count conveys purpose precisely.

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 instructs the user to provide one of url, html, or session_id, which gives parameter usage guidance. However, it does not explicitly state when to choose this tool over alternatives like audit_perceivable or audit_operable. The context is implied by the tool name, but no when-not or alternative recommendations are provided.

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