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

No annotations exist, so the description carries the full burden and does: it discloses that the tool does NOT execute the scan ('axe-core needs a real browser DOM'), that the score comes from a local run, the required install step (npm i -D @axe-core/playwright), and the exact return shape including status values of PENDING_EXECUTION. This is exactly the kind of non-obvious behavior an agent needs.

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?

Front-loaded with purpose, then exclusion, then the critical non-execution caveat. Slightly padded by both an inline 'Returns JSON: {...}' block and separate sentences covering install_command/run_command, which partially restate each other, but no sentence is truly wasted.

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?

For a three-parameter tool with no annotations and no output schema, the description covers purpose, exclusions, the non-obvious non-execution model, the prerequisite install command, and the full response structure. Nothing an agent needs to invoke or interpret the tool correctly is missing.

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 the baseline is 3; the description adds genuine meaning on top by explaining the purpose of config ('customize axe.configure(), for example with branding overrides or rule disables') and the default behavior when omitted ('Omit for standard WCAG 2.2 AA'). It does not add anything for ruleset beyond what the schema already enumerates.

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 and resource ('Get the Designesy WCAG 2.2 AA accessibility verification framework'), quantifies the deliverable (11 checks a01-a11 plus a Playwright + axe-core script template), and names the sibling it differs from (designesy_score). An agent can distinguish it from designesy_score, designesy_drift_score, and designesy_contract without opening any schema.

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?

Explicit both ways: 'Use this to audit a site for accessibility violations' and 'When NOT to use: for a full design-contract score (not just a11y), use designesy_score.' It also pre-empts the most likely misfire by stating the tool does not run the scan, so an agent cannot expect results from this call alone.

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