verify_x402_payment

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

With no annotations, the description carries the full burden of behavioral disclosure. It provides a detailed return contract, including status semantics ('valid', 'settled', 'invalid') and explains how omitting or supplying channelId changes the outcome. It does not explicitly state that the tool is read-only or disclose side effects, but the verify-oriented description and deterministic status rules provide substantial transparency.

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 well-organized into purpose, usage, and return/status semantics, with no filler. It is longer than minimal, but the length is justified because there is no output schema and the return contract must be spelled out. A small amount of redundancy exists between the opening summary and the status definitions, but it does not hurt clarity.

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?

Given no annotations, no output schema, and only two parameters, the description is largely complete: it explains what the tool does, when to use it, the returned JSON shape, and the meaning of each status. Minor gaps remain, such as explicit guidance on when to use get_channel_status instead and any error/rate-limit behavior, but the essential information for correct invocation is present.

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%, so the baseline is 3. The description goes beyond the schema by explaining how channelId affects the status result: supplying it yields 'settled', omitting it yields 'valid'. It also clarifies what makes a proof 'invalid' in terms of Base58 format, adding valuable parameter-level meaning.

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 and resource: 'Verify cryptographic validity and on-chain settlement state of an x402 payment proof or transaction signature.' It also explicitly distinguishes itself from the sibling screen_solana_address by noting that the screen tool is for sanctions/threat screening while this tool is for payment proof validation.

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 clearly states when to use the tool: to confirm a payment proof is well-formed and whether it has settled against a channel. It also gives an explicit alternative by saying to prefer screen_solana_address for sanctions/threat screening. However, it does not address when to prefer get_channel_status or generate_compliance_report, leaving some sibling differentiation incomplete.

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