Look up an Indian company or LLP

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

Annotations already cover read-only, idempotent, non-destructive, closed-world behavior, so the description's job is to add what they don't. It does: it discloses exactly what the record contains (status, incorporation date, ROC, state, capital, activity, board with names/DINs/designations), expressly excludes personal contacts, and instructs citing source_url — valuable return-shape and provenance context given there is no output schema.

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 compact sentences, front-loaded with what the tool retrieves and keyed on identifier format, then the returned fields and the citation requirement. No filler; every clause carries information an agent would otherwise have to guess.

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, no-output-schema tool whose safety profile is already covered by annotations, the description supplies the missing pieces: valid identifier formats with examples, the full content of the returned record, the no-personal-contacts caveat, and the source_url citation requirement. Nothing essential is left unspecified.

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?

With a single parameter and 100% schema description coverage, the baseline is 3, but the description goes beyond the schema's plain 'CIN, LLPIN or FCRN' by giving the CIN's 21-character length and a concrete example (U72900KA2015PTC080123) and an LLPIN example, which helps an agent construct a valid value.

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 (look up / retrieve registry record) and resource (one Indian company, LLP or foreign company) plus the keying identifier. It is clearly distinguishable from siblings like search_companies (name search) and lookup_director (person lookup) without opening any 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?

The phrase 'by identifier: CIN, LLPIN or FCRN' implicitly scopes usage to identifier-based lookup and thereby routes away from search_companies, and it specifies the valid id formats. It stops short of explicitly naming when NOT to use it (e.g. to find a company by name, use search_companies).

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