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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, open-world), so the bar is lower. The description nonetheless adds genuinely new behavioral context absent from annotations: the cost (0.009 USDC) and the billing rule that failed inspections are not charged. It stops short of describing what an inspection returns or any rate limits.

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?

A single dense sentence, front-loaded with the core purpose and semicolon-packed with pricing terms. Nothing is wasted and no filler precedes the key information.

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?

Adequate for a one-parameter read-only tool, but with no output schema the description supplies nothing about what an inspection yields (a score? a report?), and the lone 'url' parameter is left undocumented. It covers purpose, protocols, and billing but leaves return semantics to inference.

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?

Only one parameter ('url') with 0% schema description coverage, so the description carries the burden. It never explains what the URL should point to, though the schema's example ('https://agent.example/.well-known/agent.json') and the protocol list give strong implicit hints. Marginal added value.

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+resource ('agent inspection') and enumerates the supported protocols (x402, A2A, ERC-8004, OpenAPI, MCP), which is well beyond a restatement of the name. It does not, however, distinguish itself from sibling-like tools such as preflight, verify, or try_service.

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 'pre-payment' qualifier implies when to reach for it (before paying an agent), which is useful implicit context. But no explicit when/when-not rules and no named alternatives (preflight, verify) are given, so routing remains inferential.

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