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

Annotations only say readOnlyHint=false and openWorldHint=true; the description adds that the receipt is Ed25519-signed, that billing is free-tier-only with x402 not yet live, and that an Idempotency-Key is supported. It stops short of describing auth requirements or what the signed receipt contains, but contributes meaningful context beyond the annotations.

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, front-loaded with the core action, then the key call constraint, then availability. No filler and nothing buried.

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 5-param mutation tool with no output schema, the definition covers the critical do-not-do (raw secrets), idempotency, and availability. The remaining gap is that it never indicates what comes back from issuing — a receipt id/object — which would help an agent chain into verify_receipt.

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 coverage is already 100%, so the baseline is 3; the description earns a bump by adding the safety-critical semantic that hashes must be of canonical inputs/outputs and never raw secrets, which is guidance the schema's pattern alone doesn't convey.

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 and resource: 'Issue an Ed25519-signed ActSeal receipt for a tool action.' The issue-vs-verify split against the sibling verify_receipt is obvious from the verb, but the description never names or contrasts the sibling explicitly.

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?

'Pass SHA-256 hex hashes of inputs/outputs — never raw secrets' gives a real usage constraint, and 'Free tier only; x402 not live' signals availability. However, it doesn't say when to reach for this versus verify_receipt, nor any prerequisite/auth conditions for calling it.

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

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

Annotations already declare readOnlyHint and openWorldHint, so the description's added value is disclosing the response contents (valid/invalid, receipt payload, issuer public key) and the public/no-auth access condition. It stops short of explaining what an invalid verdict implies or how verification is performed.

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 short sentences with zero filler; the operation and its access scope come first, followed by the expected outputs.

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 read-only tool with no output schema, the description covers the operation, access model, and return contents. It could say more about the shape or meaning of the payload field, but an agent has enough to call it correctly.

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 coverage is 100% and already documents the id pattern and its origin in issue_receipt. The description only restates 'by id' without adding format or constraint detail beyond the schema, so the baseline 3 applies.

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 and resource (verify a receipt by id), and 'verify' contrasts naturally with the sibling issue_receipt. It does not explicitly name the sibling or spell out the boundary, so it falls short of a 5.

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?

'(public)' implies no authentication is needed, which is useful context, but there is no explicit statement of when to use this versus issue_receipt or any other verification path. Usage is inferable rather than stated.

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