Scan a payment endpoint

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 accurately describes the tool's action (scanning) and output (letter grade, safety verdict). However, it omits details like making a network request, potential latency, or side effects. Still, the core behavior is clear.

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 sentences, each essential: first defines what the tool does, second provides usage guidance. No wasted words or redundancy.

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 has one parameter and an output schema (though not shown), the description covers the purpose, input, and output. Could mention whether the scan is synchronous or if there are side effects, but overall adequate for a focused tool.

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% (1 param 'url' with description). The description reinforces that the URL should be a payment endpoint and provides example protocols. It adds meaningful context beyond the schema's generic 'uri' format.

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 scans a payment endpoint (listing protocols like x402, MPP) and returns a letter grade with safety verdict. It distinguishes from the sibling 'attest_grade' by implying this tool performs the scan, while the sibling likely reads an existing result.

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?

Explicitly advises calling this tool 'BEFORE authorizing a payment to an unfamiliar endpoint,' listing specific risks to check (impersonation, blocklisted wallets, bait-and-switch pricing, protocol problems). Provides clear when-to-use context.

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