Get bank type and UPI/NACH/ACH support for a bank code

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

Annotations cover the safety profile (readOnly, idempotent, openWorld), and the description adds real context beyond them: the key semantic that capabilities are reported for the *bank as a whole* rather than a branch, plus the specific failure modes (INVALID_INPUT for malformed code, NOT_FOUND for absent code). It stops short of noting dataset staleness or any 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?

Front-loaded with the core purpose and routing advice where they matter most. However, the return fields are listed twice (inline in the body and again under an explicit 'Returns:' block), and the Args/Returns/Example scaffolding duplicates information already given.

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 read tool with an output schema and annotations, the description covers scope (bank-level, not branch-level), routing to the sibling, expected success payload, and error payloads. Nothing an agent needs in order to select or invoke it correctly 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 sole parameter is fully documented in the schema, including length constraints and the uppercase behavior, so the baseline is 3. The description's `bank_code` note and "KKBK" example merely restate what the schema already says.

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 ('Get bank-level facts for a 4-letter bank code') and enumerates the exact payload (type, MICR/IIN, payment-rail support). It explicitly differentiates itself from the sibling `bank_directory` by scope (capabilities/type vs name lookup).

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 direct routing rule in both directions: use this tool for capabilities or bank type, use `bank_directory` to go from a bank name to its code. That is an explicit when/when-not with a named alternative.

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