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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint, so the safety profile is covered structurally. The description adds a pricing note and an ambiguous claim that 'each result states its scope,' but says nothing about failure handling for invalid items, partial-batch behavior, or rate limits.

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?

Two short sentences, front-loaded with the core capability and the item cap. The 'each result states its scope' sentence is somewhat vague and contributes less than the other two, but there is no 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?

With an output schema present, return values need not be explained, and the description does cover batch size limits, item shape, and the cost rationale. It could be stronger on per-item error behavior, but nothing essential for invocation is missing.

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% and the single 'items' parameter is fully specified in the schema, so the 3 baseline applies. The description restates the {tool, value} shape and the 50-item cap but adds no syntax or format detail beyond the schema.

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 states a specific action and resource: running up to 50 {tool, value} identifier checks in a single request. This clearly distinguishes it from the single-check siblings like iban_check and lei_check, 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?

The line about comparing batch quotes with individual quotes implies the batch is a cost-saving alternative to per-item calls, and 'savings depend on batch size' hints that small batches may not be worth it. However, no explicit threshold or when-not-to-use rule is given, leaving the agent to infer the tradeoff.

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