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

Annotations already cover readOnly, idempotent, and openWorld, but the description adds genuinely non-obvious operational context: the $0.05 x402/USDC-on-Base pricing and the fact that it returns payment requirements unless payment_signature is supplied. That payment-gating behavior is the kind of detail an agent cannot infer from structured fields.

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?

Front-loads the category tag and purpose, then usage, price, payment behavior, and a sample path in compact sentences. Slightly dense but every sentence carries distinct 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?

With full schema coverage, no output schema, and annotations handling the safety profile, the description covers the remaining gaps: cost, the x402 payment flow, and a sample endpoint. Adequate for an agent to call it 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%, so limit, lists, since, change_types, and payment_signature are all fully documented in the schema. The description adds no syntax or format detail beyond it, so the baseline 3 applies.

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: 'See what changed on official sanctions lists since your last check.' The delta/change-monitoring framing distinguishes it conceptually from the screening siblings (screen_sanctions, batch_sanctions_screen), though it never names them explicitly.

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?

'Use when re-screening customers against new designations or monitoring list updates' gives a clear situational trigger. It lacks an explicit when-not or a named alternative, so it stops short of the top band.

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