lookup_ifsc

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

This is an annotation contradiction: the description says the tool 'attempts live lookup at ifsc.razorpay.com with 3s timeout,' which is an open-world/external-network behavior, while annotations declare openWorldHint=false. The description helpfully discloses the fallback, but the metadata is internally inconsistent, so the behavioral signal is unreliable.

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?

The description is well-organized with a one-line purpose, a usage context, Args, Returns, and Notes. No sentence is wasted, though the Args section partially restates schema information. Overall it is compact and scannable.

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 single-parameter lookup tool, the description covers the key agent-relevant details: when to use it, normalized input handling, return envelope, fallback behavior, and timeout. It is only pulled back from a 5 by the contradictory open-world annotation and the lack of explicit routing guidance to bulk or alternative lookup siblings.

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 schema already documents the parameter with example and length constraints, so schema coverage is 100%. The description adds meaningful behavior beyond the schema by stating that input is case-insensitive and that whitespace is trimmed, which is useful for validating user-supplied IFSC codes.

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 names a specific verb and resource: look up an Indian IFSC code, with a clear distinction from validate-only tools by offering bank branch details. It also signals the bundled dataset plus live fallback, so an agent can distinguish it from bulk/validation sibling tools without opening the schema.

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 clearly states when to use the tool: 'when you need bank branch details from an IFSC code in invoices, onboarding forms, or payment validation workflows.' However, it does not explicitly say when not to use alternatives like bulk_validate_ifsc or lookup_bank, so exclusions are incomplete.

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