validate_cin

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

Annotations already establish the read-only and idempotent behavior, so the description adds useful behavioral detail: spaces and hyphens are stripped automatically, the output is a standard envelope, and there is no public checksum. This helps the agent set correct expectations without contradicting the 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?

The description is compact, well-sectioned, and front-loaded with the core purpose. Each section (Use when, Args, Returns, Notes) earns its place and provides practical information without 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 single-parameter, read-only tool with an output schema, this description covers the input contract, normalization behavior, output structure, and a key validation limitation. Nothing essential appears to be missing for a successful invocation.

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 cin parameter fully, but the description adds the operational note that spaces/hyphens are automatically stripped and reinforces the canonical 21-character format. That goes beyond the schema's 'spaces/hyphens allowed' wording and clarifies input normalization.

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 opens with a specific verb and resource: 'Validate and decode an Indian CIN.' It also lists concrete outputs such as listing status, NIC code, state, year, company type, and serial number, which makes the tool's purpose easy to distinguish from sibling validators like validate_pan or validate_din.

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 explicit trigger conditions: use when verifying company registration data or extracting structured fields from a CIN. It doesn't name alternatives or state when not to use this tool, but the context is clear enough for an agent to route correctly.

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