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

With no annotations, the description carries the full burden and discloses key behavioral traits: prefix matching, case-insensitivity, no wildcards, and the exact return fields (IČOs, names, addresses). This goes well beyond a generic 'search' and gives an agent clear expectations, though it omits rate limits or error behavior.

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?

One information-dense sentence with no filler. The key action and source are front-loaded, and every clause contributes to either behavior or output.

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 two-parameter tool with no output schema, the description is remarkably complete: it explains matching semantics, the exact return fields, and the intended follow-up use. An agent can safely invoke it without additional inference.

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 baseline is 3. The description adds meaning to the 'name' parameter by specifying prefix match, case-insensitivity, and no wildcards—details not in the schema. It does not elaborate on 'limit', but that parameter is already well-described in the schema with min/max/default.

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 ('search'), a specific resource (ARES company database), and the core behavior (prefix match, case-insensitive). It distinguishes itself from siblings like company_lookup by focusing on name-based search rather than exact identifiers.

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 by stating results are 'for further lookups', hinting that this tool is a precursor to other tools. However, it never explicitly contrasts with alternatives like company_lookup or validate_cz, nor states when not to use it.

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