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

Annotations already signal read-only and idempotent behavior. The description adds value beyond those hints by specifying that the checks are deterministic, structural, and each state their own scope, while 'one call, one receipt' signals the expected response shape. No contradiction with annotations.

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?

Three short sentences, each earns its place: the first states the offer, the second defines the behavioral nature, and the third gives the procurement context. There is no filler or redundant restating of schema fields.

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?

Given the rich annotations, 100% parameter coverage, and presence of an output schema, the description is complete enough. It supplies the missing decision-making context: why this tool exists, when to use it, and what kind of result to expect.

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%, so the schema already documents each parameter's format and optionality. The description lists the four identifiers and frames them as a combined verification pack, but it does not add parameter-level semantics beyond what the schema provides.

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 concrete deliverable: one call returns a receipt of GSTIN, PAN, UPI VPA, and IFSC structural checks for an Indian counterparty. It clearly distinguishes itself from single-identifier siblings like gstin_check and ifsc_check by being a combined pack, even though those siblings are not named.

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 description gives a clear intended context: cross-border procurement where the buyer is an agent that cannot open an INR account. It implies one call instead of four separate checks, but it does not explicitly state when NOT to use it or name alternatives like batch_validate or vendor_onboarding_pack.

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