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

Annotations already cover read-only, idempotent, non-destructive, closed-world behavior, so the bar is lower; the description still adds useful context by disclosing that the call is free and that results carry old value, new value, and registry date. It does not say how far back the history goes or whether results are exhaustive, which keeps it from a 5.

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 front-loaded sentence that leads with the resource and then the returned fields, closing with the cost note. Dense but every clause (field list, old/new/date trio, 'Gratuit') contributes information; no filler.

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?

With no output schema, the description does the work of describing the return shape (tracked fields plus old/new value and date), which is enough for an agent to know what it will get. Missing only depth/coverage caveats about the history window.

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?

There is a single parameter with 100% schema description coverage, and the schema already explains the optional RO prefix and the fallback to cauta_firma. The description adds nothing about the CUI beyond what the schema provides, so the baseline 3 applies.

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 resource (changes recorded in the trade registry for a company) and enumerates the tracked fields (name, status, address, CAEN, registration number) with old/new values and dates. This clearly separates it from current-state siblings like profil_firma, though it never names an alternative explicitly.

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?

Usage is only implied: an agent can infer it should call this when it needs change history rather than a snapshot, but there is no explicit 'use this when…' or 'for current data use profil_firma' routing. The schema mentions cauta_firma, but that guidance lives in the schema, not the description.

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