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

With no annotations, the description carries full burden. It explicitly states 'Read-only', describes the output values (safe_to_interact false/null/true), and lists the safety checks performed. This is thorough and goes beyond the schema.

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 longer than the calibration high example but remains focused and front-loaded with the core question. Some redundancy exists between 'pre-payment / pre-interaction' and 'THE check before an agent sends funds...', but each sentence adds useful information.

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 simple schema, lack of annotations, and no output schema, the description provides sufficient context: input requirements, return semantics, use cases, and read-only nature. It is complete for an agent to decide when and how to use this 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%, so baseline is 3. The description adds little beyond the schema: it reinforces '0x address' format (already in schema) and does not elaborate on chain values. The schema adequately documents both parameters.

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 what the tool does: it screens an address before payment or interaction, checking for scam/drain/sanction flags, known entity status, and on-chain track record. It distinguishes itself from siblings by positioning as the pre-payment/interaction check and specifying the safe_to_interact return value.

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 explicit use cases: 'THE check before an agent sends funds to an address, pays an x402 endpoint, receives a transfer, or approves a contract.' It does not mention alternatives or exclusions, but the context is clear and actionable.

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