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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), and the description adds genuinely non-structural behavior: fuzzy matching semantics, a default 5-year lookback for former PEPs, and the full payment model (0.005 USDC via x402, 3 credits, first 5 paid calls/day free). Pricing and free-tier quota are exactly the kind of context that changes how an agent plans a call.

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-loaded with the when-to-use clause, then scope, then mechanics, then pricing — a sensible ordering. It is dense but every sentence carries information; the coverage enumeration is long yet functional.

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, and the description does not say what a result looks like (boolean, match score, position details), which is the main remaining gap for an agent deciding how to consume the response. Everything needed to decide whether and how to invoke it is present.

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 the baseline is 3; the description still adds value by framing the matching behavior (fuzzy matching against positions, country and dates, default 5-year recency window), which tells the agent why country and birth_year disambiguate. It stops short of explaining how the api_key interacts with the free-tier path beyond what the schema says.

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 ('check whether a person is a politically exposed person') and then enumerates the exact coverage scope (heads of state, ministers, central bank governors, MEPs/MPs across EU/EEA/UK/US/CH, current or former). An agent knows precisely what the tool returns a verdict on without opening the schema.

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 a clear triggering condition ('Use when you must check ... for AML/KYC') and names a complementary tool ('Pairs with sanctions screening'). It does not distinguish itself from the sibling pep_batch (single vs. bulk), so the multi-person alternative is left implicit.

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