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

Annotations already declare read-only, idempotent, open-world, and non-destructive behavior. The description adds meaningful context beyond those: it is free during LIVE_FREE observation, requires no API key, and never signs or sends a payment. This covers auth, cost, and payment safety, though it does not discuss rate limits or other operational constraints.

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 purpose is front-loaded in the first sentence, followed by a justification sentence and a safety/access sentence. The second sentence is a long list but each item earns its place by clarifying what the tool replaces, and there is little wasted text.

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?

An output schema exists, so return values need not be explained. The description covers purpose, usage context, cost, auth, and payment safety for a read-only audit tool with no siblings, leaving no critical gap for an agent to call it correctly.

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 description coverage is 100%, so both parameters are already documented in the input schema. The description mentions x402 resource observation but does not add syntax, format, or usage guidance beyond what the schema provides, making the baseline of 3 appropriate.

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 ('public HTTP(S) website') with the exact domain ('AI-agent commerce readiness'). It distinguishes itself from manual rebuilding by naming the checks it replaces, so an agent knows precisely what the tool does.

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?

Explicitly says to use this instead of rebuilding UCP discovery, structured-commerce checks, ACP evidence handling, x402 observation, remediation, and verification evidence yourself. It provides clear context for when this tool is appropriate, though it does not state explicit exclusions or prerequisites beyond the read-only/no-key framing.

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