Verify GSTIN

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

With no annotations, the description carries the behavioral burden. It discloses that no taxpayer session is required and enumerates the returned data fields. It does not discuss invalid-GSTIN behavior or data freshness, but for a read-only public lookup this is reasonably transparent.

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 front-load the purpose and return values, then add the key access constraint. Every sentence earns its place with no filler.

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-only verification tool with no output schema, the description covers the input format, the purpose, the key return fields, and the access requirement. Nothing essential for an agent to 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 coverage is 100% and the schema already documents the gstin parameter as a '15-character GSTIN, e.g. 29AFSPB9500E1ZY'. The description only repeats the 15-character constraint and adds no new semantic detail, so the baseline 3 applies.

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 states a specific verb ('Verify') and resource ('a GST-registered business by its 15-character GSTIN'), and lists the returned fields. This clearly distinguishes it from sibling tools like search_gstin_by_pan and the taxpayer-session tools, even without naming them.

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 clear context: this is for verifying a GSTIN and does not require a taxpayer session, which signals when it is appropriate. However, it does not explicitly name alternatives or state when-not-to-use it, so it stops short of full exclusion guidance.

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