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

The annotations already declare read-only, idempotent, non-destructive, and closed-world behavior, so the description carries less burden. It adds the useful access note 'Included in every plan' and restates the recent-registration scope, but it does not discuss return format, rate limits, or other behavioral details beyond that.

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 are used efficiently: the first front-loads the core count purpose and optional filters, and the second adds a short access note. There is no filler or repetition.

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 simple read-only count tool with rich schema descriptions and safety annotations, the definition gives enough context to invoke it correctly. The main missing context is explicit routing against the closely related list_new_companies sibling.

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%, so the input schema already documents all four optional parameters in detail. The description names the same filters in prose but adds no syntax, defaults, or interpretation beyond what the schema provides.

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 clearly states a count operation over newly registered companies and sole traders in Romania within a recent time window. The verb is implicit in 'How many' and the resource and scope are specific, but it does not explicitly distinguish the tool from the sibling list_new_companies.

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?

It gives implied usage context by stating that the count can be narrowed by CAEN field, county, and natural-person status. However, it does not say when to use this tool instead of list_new_companies or other siblings, and it offers no explicit exclusions or prerequisites.

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