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

Annotations already signal readOnly, openWorld, idempotent, and non-destructive behavior, and the description does not contradict these. It adds genuine extra context: 'deterministic' behavior, a $0.002 per-call x402 price, and explicit non-obligations (no identity credentials, no legal advice, no downstream guarantee). This is meaningful added transparency beyond the structured hints, though it omits response-shape and error behavior.

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 description is compact and each sentence adds something: purpose/scope, negative limits, and cost. The opening sentence is a dense noun phrase with a long list, but it is front-loaded and contains no filler. Minor redundancy of 'Paid' appears twice, but otherwise remains disciplined for a tool with this much surface area.

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?

The tool is complex: 7 modes, 10 mostly undocumented parameters, nested objects, and no output schema, so the description needs to explain mode-specific behavior and return semantics to be complete. It supplies only a high-level domain list, exclusions, and price; it never explains what a 'preflight' or 'verify' mode returns, how parameters combine, or how results should be interpreted. For an agent to correctly invoke this multi-mode endpoint, this is insufficient context.

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?

Input schema has 0% description coverage and 10 parameters, so the description carries a heavy burden for parameter meaning. It loosely maps the domains ('permission constraints' → constraints/permissions, 'schema compatibility' → schema, 'procurement comparison' → offers), but it does not explain the core verification parameters such as expected, observed, evidence, protocol, or request. This is partial compensation at best.

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 defines the tool as 'deterministic technical assurance' across a list of agent-commerce concerns (trust evidence, permission constraints, outcome/provenance consistency, schema compatibility, procurement comparison), giving a functional category rather than a single specific verb. The broad multi-domain phrasing and overlap with numerous sibling verification/assurance tools make it hard to distinguish without looking at the mode enum. It is clearer than a tautology but not a crisp action statement.

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 description implies the intended use cases through its list of assurance domains and states exclusions ('does not issue identity credentials, provide legal advice, or guarantee downstream outcomes'). It also flags that this is a paid resource, which is useful cost context. However, it names no sibling alternatives and gives no explicit when-to-use/when-not-to-use decision guidance, leaving tool selection inference-heavy.

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