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

The description declares the tool is read-only, which is valuable behavioral disclosure given no annotations. However, it does not describe the outcome of verification (success/failure returns, errors, or response structure), leaving a significant gap for a verification tool.

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, front-loaded with the action and key checks, ending with 'Read-only'. Every word earns its place with no filler.

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?

Despite the tool's complexity (one opaque parameter, no output schema, no annotations), the description provides only a minimal summary. It omits return behavior, failure modes, prerequisites, and parameter structure, leaving the agent underinformed for 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?

The single 'receipt' parameter has an empty schema with 0% description coverage, so the description must compensate. It only mentions the receipt is 'received (e.g. opened from your v2 mailbox)', providing a source hint but no structural details, format, or required fields, which is insufficient for safe usage.

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 clearly states it verifies a settlement receipt by checking digest, relayer signature, and signed terms, and explicitly notes it is read-only. This distinguishes it from sibling verification tools like robyn_payment_request_verify or robyn_refusal_verify, which target different objects.

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?

It gives a concrete use case ('opened from your v2 mailbox') that implies when to use it, but does not explicitly name alternatives or state when not to use. This is useful context, though a note distinguishing it from other verification tools would strengthen it.

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