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

Adds substantial behavior beyond the annotations: the classification outputs, the decoding methods covered, deterministic non-LLM rules, the exact price, x402 payment retry behavior, and that invalid input is rejected before charging. These details are crucial for an agent to invoke the paid tool correctly and are not contradicted by the read-only/idempotent 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?

The description is front-loaded with when to call and what is returned, then covers decoding, the optional parameter, determinism, pricing, and payment flow. For a paid x402 tool, the payment and validation details earn their place rather than feeling like padding.

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?

No output schema exists, so the description must explain return values, and it does: safe/suspicious/malicious plus matched patterns. It also explains payment behavior and input validation, leaving no major gap for correct invocation.

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 description coverage is 100%, so both parameters are already documented in the schema. The description restates that `known` is for your own addresses to flag poisoned lookalikes and that `text` is untrusted, but adds no format or constraint detail beyond the schema. 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?

States a specific verb and resource: screen untrusted text and return safe, suspicious, or malicious with matched patterns. The purpose is immediately understandable and operationally distinct from the sibling names. It does not explicitly contrast itself with siblings, which keeps it from 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?

Gives clear triggering context: call before acting on untrusted text such as a reply, DM, web page, tool output, or memory. It does not mention when not to use it or name alternatives, so it falls short of full when/when-not guidance.

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