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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds a valuable caveat: 'Signature validity does not prove source truth.' This is important behavioral context beyond the annotations, warning the agent about a common misinterpretation of verification results.

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?

Two sentences with no wasted words. The core action is front-loaded, and the critical caveat is delivered in a short second sentence. Every word earns its place.

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 read-only verification tool with strong annotations, the description is mostly complete. However, with no output schema and 0% parameter coverage, the agent is left without details on what the verification result looks like or how the optional receipt/digest parameters interact with the proof. The caveat about source truth is helpful but does not fully compensate for the missing return-value and parameter semantics.

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 0%, so the description carries the burden of explaining parameters. It mentions 'proof', 'receipt', and 'result digest' but does not explain the format or relationship between them beyond the schema's types. The description adds some semantic context (e.g., receipt and digest are bound to the proof) but not enough to fully compensate for the 0% schema coverage.

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 states a specific verb ('Verify') and resource ('a ProofRail proof'), and mentions the optional bound x402 receipt and result digest. It does not explicitly distinguish itself from siblings, but the verb 'verify' plus the ProofRail-specific resource is clear enough to separate it from execution/discovery tools.

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 when to use the tool: when you need to verify a ProofRail proof and optionally its bound receipt/digest. It does not explicitly state when not to use it or name alternatives, but the context is reasonably clear given the sibling names.

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