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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, and the description is consistent with them — no contradiction. The description adds value beyond annotations by disclosing that the output is a 'canonical' normalized rule carrying editorial status and official sources, which is useful behavioral context an agent could not infer from the schema alone.

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?

Two sentences, both earning their place: the first front-loads the core purpose and return contents, the second clarifies the most domain-specific parameter. There is no filler and no repetition of what the annotations or schema already provide.

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?

An output schema exists, so return values need not be described, and annotations cover the safety profile — allowing the description to focus on purpose and parameters. The only meaningful gaps are the undocumented as_of parameter and the absence of tool-selection guidance, but for a read-only 3-parameter tool with one required parameter this is otherwise adequate.

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?

With 0% schema description coverage, the description carries the burden and notably clarifies applicable_on as 'la date du contrat ou des faits à examiner,' adding domain meaning that the bare parameter name would not convey. However, as_of is left entirely unexplained despite its temporal significance in a 'versioned rule' tool, and rule_id is only self-evident by name — so compensation is partial.

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 uses a specific verb ('Retourne') tied to a specific resource ('une règle canonique') and enumerates exactly what is returned: application period, editorial status, and official sources. This is a clear statement of purpose, though it does not explicitly distinguish itself from siblings such as scoreconso_get_template or scoreconso_get_evidence_checklist; differentiation relies on the title and the domain-specific return contents.

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 use case is implied rather than stated: the description never tells an agent when to choose get_rule over a sibling, nor does it name any alternative. The only guidance, 'applicable_on désigne la date du contrat ou des faits à examiner,' is a parameter clarification that hints at the intended scenario but offers no explicit when/when-not rules.

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