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

Annotations already declare readOnlyHint/idempotent/openWorld=false, so this is clearly a safe deterministic computation and the description needn't restate that. It adds the useful detail that the comparison is against 2026 rules, but says nothing about what is returned (a verdict? both thresholds? a status per regime) despite there being no output schema.

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 tight, front-loaded sentence with no filler. It is efficient, though arguably too terse for the decision-support nature of the tool.

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 rule-evaluation tool with no output schema, the description should state what result comes back and how to read it (e.g., threshold exceeded vs. franchise maintained). It also leaves the mixed-activity path undocumented. As written, the agent knows what the tool is about but not what it will get.

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 75%, so the schema carries most of the meaning, including the activity enum values and the 'mixte' branch. The description adds no parameter-level information — nothing on how caAnnuel vs caServicesMixte interact or when depassementAnneePrecedente matters.

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?

Specific verb ('Situe ... par rapport aux plafonds') plus two concrete resources: micro-entreprise ceilings and 2026 VAT franchise thresholds. An agent can tell this is a threshold-positioning calculation. It does not, however, distinguish itself from overlapping siblings such as auto_entrepreneur or tva_freelance.

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?

No when-to-use statement, no exclusions, and no pointer to the clearly overlapping siblings (auto_entrepreneur, tva_freelance, freelance_tjm_ca_net). The agent must infer the use case entirely from the one-line purpose.

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