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

Annotations already cover read-only, idempotent, non-destructive, closed-world behavior, so the description is free to add real value — and it does: it discloses that results are split into two independently paginated groups (confirmed and currency_leads) with total_items/total_pages/items, and that a currency lead has unknown country coverage. That return-shape disclosure matters especially since there is no output schema.

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?

Four tight sentences: purpose first, then the matching constraint, then the pagination/response model, then the two data caveats. No filler, and the most important constraint is front-loaded.

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 9-parameter, zero-required search tool with no output schema, the description covers the response structure and the meaning of the two result groups, which is the main thing an agent could not otherwise know. Minor gaps remain around what 'reviewed' means and how pagination interacts with empty groups (left to the schema), but nothing essential 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 coverage is high (78%), so per-parameter docs are largely handled there. The description still contributes meaning the schema cannot express: the AND-across-categories matching semantics ('Filters must match the same scope'), the shared page/limit across both result groups, and the unknown/unknown-data convention. It does not explain the multi-value `methods`/`integrations` OR behavior beyond what the schema says, keeping it at 4.

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+resource ('Find reviewed public payment product scopes') and enumerates the filter dimensions, so the agent knows exactly what is being searched. It does not distinguish itself from siblings like get_payment_capabilities, search_providers, or compare_payment_capabilities, so it falls short of a 5.

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 sentence 'Filters must match the same scope' implies the tool is for narrowing down product scopes by combined criteria, but there is no explicit when-to-use vs. when-to-use-a-sibling guidance despite four closely related payment/provider tools. Usage is inferable but not stated.

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