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

Annotations already indicate readOnly, idempotent, and non-destructive behavior. The description adds substantial transparency beyond that by clearly listing excluded fields (evidence, source URLs, address, incorporation, annual-report, law-violation) and stating that verification depth is not accepted.

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 sentences with no wasted words. The free/limited nature is front-loaded, the return scope is precise, and the pointer to the paid alternative is placed last. Every sentence contributes meaning.

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 read-only, idempotent lookup with an output schema and 100% schema-described parameters, the description fully covers purpose, exclusions, and routing. Nothing essential is missing for an agent to decide whether to call this tool.

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 every parameter already has a clear description. The tool description does not add parameter-level meaning beyond the schema, which is acceptable given full schema coverage. It does reinforce that company_name or company_number is needed, but the schema already conveys this.

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 ('preview'), a resource ('Israeli company identity'), and a clear scope ('free and limited'). It explicitly enumerates what is returned and what is never returned, and distinguishes itself from the paid verify_company tool by contrast.

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 explicitly tells the agent when to use this tool versus the paid alternative: use preview_company for a free limited identity preview, and use verify_company when a complete evidence-backed public-registry result is needed.

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