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

Annotations already declare readOnly, idempotent, non-destructive and closed-world behavior, so the bar is lower. The description adds real value with "Gratuit" and the note that prefixes of the code are accepted, but says nothing about result format, match ranking, or behavior on no-match.

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 short sentences, front-loaded with the core action and examples, ending with the routing hint. No filler and nothing repeated from the title.

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 single-parameter read-only lookup with full schema coverage and rich annotations, the description covers purpose, input forms and downstream use. Only the shape of the result (a list of codes/labels, possible empty result) is left implicit.

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% and the parameter already carries examples for both modes, so the schema does the heavy lifting. The description's "primele lui cifre" hints at prefix matching beyond what the schema states, but does not clarify matching rules or case/diacritic handling.

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 and resource ("Caută codurile CAEN") plus the two lookup modes (by activity word or by code). This is clearly distinct from the firm-oriented siblings and the examples ("transport", "software", "cofetărie") pin down the granularity of the input.

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 closing sentence establishes where the output goes ("Codul ... intră apoi în prospecteaza_firme"), which effectively tells the agent to run this before prospecting. It does not state exclusions or what to do if no match is found, so it stops short of full when/when-not guidance.

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