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

With no annotations supplied, the description carries the full burden and does well: it discloses that the call is paid at $0.05 USDC on Base or Solana, that no account or API key is needed, and that failed calls are not charged — meaningful behavioral facts an agent cannot get from structured fields. It stops short of describing latency, rate limits, or response shape, but the safety/cost profile is covered.

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?

Seven short fragments, front-loaded with 'Paid' and the resource, then checks, then price, then access terms, then endpoint. Every clause carries information; nothing is redundant or padded.

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 single-parameter paid endpoint with no output schema, the description covers what is checked, what is returned (score and A-F grade), cost, payment rails, auth requirements, and failure billing. Missing only marginal items such as turnaround time or response format details, which do not block correct invocation.

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% and the single 'url' parameter is already documented with an example format in the schema, so the description adds essentially no parameter meaning beyond that. Baseline 3 applies when the schema already does the work.

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 opens with a specific verb and resource ('Website security headers check') and enumerates exactly what is inspected: HSTS, CSP, X-Frame-Options, cookie flags, version leaks, plus a score and A-F grade. This clearly separates it from buy_audit_seo, though it never explicitly names that sibling or buy_audit_bundle, so an agent must infer the boundary from the header list rather than being told.

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?

Usage context is present but transactional rather than comparative: 'Paid', '$0.05 USDC on Base or Solana', 'No account, no API key', and 'Failed calls not charged' tell the agent the cost and prerequisites. There is no guidance on when to pick this over buy_audit_bundle or buy_audit_seo, and no exclusions, which is the main gap.

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