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

Annotations already cover safety (readOnly, idempotent, non-destructive), so the bar is lower. The description adds real value beyond them: what is returned ('the retained record and its integrity proof'), the explicit scope limit '(integrity only)', and the constraints 'free, read-only, no account' plus the public/non-personal input requirement.

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?

Three short sentences, zero filler, and the usage condition and return value are front-loaded. Every clause carries information an agent needs.

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?

Although no output schema exists, the description characterizes the return (retained record plus integrity proof) and the integrity-only scope, and it discloses the privacy/account constraints. For a single-parameter read tool this is nearly complete; the only gap is no explicit tie-break against the similar verify_gaip_receipt sibling.

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, schema coverage is 100%, and the schema already states it is 'a receipt_id returned by an earlier GAIP call'. The description echoes the same origin but adds no format, provenance, or validity details beyond what the schema provides, so this is the baseline 3.

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 (confirm) and resource (Buyer Assurance terms or delivery receipt) and names the exact input it operates on. It is clear what the tool does, though it does not distinguish itself from the sibling verify_gaip_receipt, which appears to overlap.

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?

Gives a clear triggering condition: 'Use this when you hold a Buyer Assurance terms or delivery receipt_id and want to confirm it.' It also states the preconditions (receipt_id from an earlier call, inputs public and non-personal) but names no alternative or when-not-to-use case, so it stops short of full routing guidance.

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