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

Beyond the readOnly/openWorld annotations, the description discloses what the tool actually does on the network ('passive: only fetches the page and the files it links to') and the rate limit with cost fallback ('5 free audits a day; after that... 0.01 USDC per audit via x402'). Rate limits and billing behavior are exactly the context annotations cannot carry.

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?

Three dense sentences: what it does, what it returns, then cost/rate limits. The most decision-relevant facts (scope, checks, passive behavior) are front-loaded and nothing is redundant with the schema.

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?

With no output schema, the description compensates by describing the return payload (score, grade, ordered problems with exact fixes, audit_id). Combined with the rate-limit and passivity notes, an agent has everything needed to call it correctly and to chain into verify_fixes.

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% and the single url parameter is fully documented with an example, so the schema does the heavy lifting. The description still adds a constraint the schema does not state — the page must be 'public' — which meaningfully narrows valid inputs.

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 (audit) and resource (one public web page) with concrete scope: 69 checks across ten named categories. It also implicitly contrasts with the sibling by saying the audit_id is for verify_fixes, so the agent can distinguish the two without opening either 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?

The 'pass to verify_fixes after changes' sentence gives clear sequential routing to a sibling, and 'one public web page' scopes the input. There is no explicit when-not guidance (e.g., internal/authenticated pages, batch URLs), so it stops short of a full when/when-not/alternatives statement.

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