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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, openWorld), so the bar is lower. The description adds genuinely new behavioral context: per-call pricing ($0.03), the payment mechanism (x402, USDC on Base, no account required), and a breakdown of what the response contains. It stops short of stating failure modes or latency/rate behavior, so it is not a full 5.

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 cost and payment model, then the usage condition, then the content breakdown — a sensible ordering with no filler. It is densely packed into long clauses, which slightly hurts scannability but every sentence carries 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?

For a single-parameter, paid, read-only endpoint with an output schema present, the description supplies everything the agent needs: cost, when to choose it, what sections it returns, and a sibling-relative value claim. Return-value details are correctly left to the output schema.

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?

There is a single parameter with 100% schema description coverage, and the schema already documents the format (digits with optional RO prefix) and how to obtain the value via romania_company_search. The description adds nothing about cui beyond the schema, so the baseline of 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 ('Romanian company full due-diligence report by CUI') and explicitly positions it as the aggregate of three sibling capabilities (profile, financials, KYB risk). An agent can immediately distinguish it from romania_company_profile, romania_company_financials, and romania_company_risk_kyb without opening any 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 concrete triggering scenarios (onboarding, credit, M&A screening) and names the alternative it replaces: 'would otherwise call profile, financials and risk'. The 'cheaper than three' note adds an explicit cost-based selection rule, so the routing decision is fully specified.

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