lookup_corporate_number

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

No annotations are present, so the description carries the full burden. It discloses a significant behavioral trait: results come from a live API only when NTA_APP_ID is set, otherwise it falls back to bundled synthetic data that is 'clearly tagged.' This prevents misinterpretation of data provenance and is highly valuable for the agent.

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 sentences: the first states the core purpose, the second explains the data source and fallback behavior. Every word earns its place; no fluff or redundancy.

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?

With a simple 1-parameter interface and an output schema present, the description appropriately focuses on behavior. It covers what data is returned, the conditional external dependency, and the synthetic fallback. It does not discuss error handling or prerequisites like NTA_APP_ID setup, but that is beyond the essential context for selection and 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 only defines 'number' as a string with no description, so coverage is 0%. The description partially compensates by specifying '13-digit corporate number,' adding a length constraint not present in the schema. However, it does not clarify format validation or normalization behavior, leaving a gap.

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 uses a specific verb 'enrich' and clearly identifies the resource (13-digit corporate number) and the expected result (registry data including name, address, kind, dates). This distinguishes it from sibling tools like validate_corporate_number and search_corporations_by_name.

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 implies usage: apply when you have a corporate number and need registry data. It does not explicitly name alternatives but the context makes it obvious. It also adds a critical caveat about synthetic vs real data depending on NTA_APP_ID, which guides the agent in deciding whether to trust the output.

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