how-do-i-pay

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

With no annotations provided, the description carries the burden and does well by explicitly stating 'First Dollar does not sign for you — it shows you what to run.' This prevents the false expectation that the tool executes the payment. It does not address errors or permissions, but for a simple instructional tool this is acceptable.

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 exactly two sentences with no filler. The first sentence front-loads the main purpose, and the second adds a valuable disambiguation. Every sentence 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 tool with one parameter, no output schema, and no annotations, this description covers the core outcome, input condition, and a key limitation. It does not specify the exact format of the returned commands or prerequisite wallet setup, but the sibling tool names and schema hint at the broader context, making it sufficiently complete for an agent.

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 schema already provides full coverage for the single parameter ('The raw 402 response or PAYMENT-REQUIRED header value'), so the baseline is 3. The description does not add parameter-level syntax or format guidance; its phrase 'decoded x402 challenge' actually introduces a slight conflict with the schema's 'raw' qualifier, so no extra credit is warranted.

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 uses a specific verb ('returns') and states the exact deliverable: 'specific signing steps and wallet-specific commands you can run to produce a valid payment.' It also distinguishes itself from sibling tools by noting 'First Dollar does not sign for you,' making it clear this is instructional, not an execution tool.

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 gives a clear precondition ('Given a decoded x402 challenge') and implies the user should call it when they need commands to produce a payment. It does not explicitly name alternatives or exclusions, but the context is sufficient for selection among siblings.

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