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

With no annotations, the description carries the behavioral burden. It discloses the real-world trap of obsolete CAEN Rev.1 entries, explains why guessing fails, and requires the agent to show the user what was matched. It does not detail the output structure or limit behavior, but the key behavioral risks are well covered.

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, all high-signal: the operation, the mandatory usage rule, and the rationale plus user-facing instruction. Nothing is redundant, and the most important constraint is front-loaded with 'ALWAYS.'

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 resolver with no output schema, the description covers the core requirement: what input to pass, when to call it, and what to do with the result. The only clear gaps are the meaning of 'limit' and the exact shape of the returned match data, which are minor for 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?

The description gives strong meaning to 'query' with concrete examples ('coffee shops' or 'car repair') and explains why the underlying data is dangerous to guess. However, schema coverage is 0%, and the optional 'limit' parameter is never explained, so the description only partially compensates for the schema's silence.

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 starts with a specific verb and resource: 'Resolve free text ... to CAEN activity codes.' It clearly distinguishes this tool from the sibling company-query tools by framing it as a pre-filtering resolution step rather than a lookup of 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 explicitly says 'ALWAYS call this before filtering by activity — do not guess a CAEN code.' This tells the agent when the tool must be used, what behavior to avoid, and even instructs it to expose the matched result to the user. This is unusually clear operational guidance.

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