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

No annotations are provided, so the description must carry the burden. It usefully discloses the 50-address cap and cost ('one cent a call over x402'), but it does not state whether the operation is read-only, what 'observations' contain, or how invalid or partial results are handled.

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?

Each sentence earns its place: the first covers the action, limit, and target use case; the second covers pricing. The colon before 'for an agent...' is a bit awkward, but the description remains compact and readable.

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 one-parameter call, it covers the purpose, batch limit, audience, and cost. However, with no output schema and no annotations, the description leaves 'observations' undefined and does not describe the response shape, which an agent needs to consume the result.

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?

The only parameter 'addresses' is already documented in the schema with 'Up to 50.' The description adds that these are counterparty addresses and repeats the limit, but provides no extra detail on address format or validation, so it adds little 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?

States a specific verb ('Check') and resource ('up to fifty addresses'), each returning observations, so an agent understands the bulk checking action. The batch scope is explicit, though it does not name the sibling counterparty_check to distinguish single-address checks.

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 concrete scenario: 'for an agent or a desk holding a list of counterparties before paying any of them.' It does not explicitly say when not to use it or point to an alternative for a single address, but the use-case context is clear.

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