lookup_bank

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

No annotations exist, so the description carries the full burden. It usefully discloses an auth/plan requirement and that results carry sources, but says nothing about rate limits, error behavior when the identifier is unknown, or whether the lookup is read-only (implied but unstated). Partial coverage for a tool with zero annotation support.

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 tight sentences with the core purpose front-loaded and the prerequisite second. Slightly under-specified rather than verbose, and the stray blank line adds no cost but no value either.

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 two-parameter read lookup with no output schema and no annotations, the description covers the purpose and the API-key prerequisite adequately, but leaves the parameter contract and error/lookup-miss semantics unaddressed. Adequate at best, with visible gaps.

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 0% for both parameters, so the schema offers no help. The description partially compensates by revealing that the input can be a BIC or a domestic bank identifier, which hints at what the opaque 'value' and default 'bic' identifier_type accept, but it never names the parameter or enumerates the allowed identifier types.

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 gives a specific verb and resource: 'Resolve a BIC or domestic bank identifier to registry records with sources.' That is materially more informative than the bare name and clearly differs in domain from the sibling tools (validate_ibans, generate_test_ibans), though it never names or contrasts 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?

It states a precondition (IBANGEN_API_KEY on a plan with bank intelligence) but gives no guidance on when to reach for this tool versus validate_ibans or generate_test_ibans. A precondition is not usage guidance; the agent is left to infer the routing.

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