read-this-challenge

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

No annotations are provided, so the description carries the full burden. It explicitly states the tool decodes and returns an explanation, and it enumerates the output content (how much, what asset, which chain, who to pay, what to sign). It does not explicitly address side effects or error handling, but its read-only nature is strongly implied. Omitting explicit 'read-only' and edge-case info prevents a 5.

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 two sentences with no redundant words. The first sentence states the purpose and output, the second gives precise input instructions. Every phrase earns its place, making it highly concise and well-structured.

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 the tool's simplicity (one parameter, no output schema, no annotations), the description is complete. It explains what the tool does, what input to provide, and what the output will contain. No critical information is missing for an agent to select and use the tool 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% for the single parameter 'challenge', which already explains it accepts the raw 402 body or the PAYMENT-REQUIRED header. The description repeats this instruction and adds no new semantic detail about the parameter format or variations. Baseline 3 is appropriate.

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 the tool's function: it decodes an HTTP 402 x402 payment challenge into a plain explanation, listing the specific elements it extracts (amount, asset, chain, payee, signature). This is a specific verb+resource and distinguishes it from sibling tools that explain concepts rather than decode a given challenge.

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 provides clear usage context: paste the raw 402 response body or the PAYMENT-REQUIRED header value. It implies this should be used when you have a 402 challenge to understand, and it aligns with the sibling tools' educational nature. However, it does not explicitly mention alternatives or exclusionary conditions, so it does not reach a 5.

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