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

Beyond the annotations (readOnly, idempotent, non-destructive), the description discloses the required scope (jobs:read), the auth requirement (own Fonciq API key as Bearer fq_live_…/fq_test_…), and that the call produces no new document and is not billed. That is exactly the kind of operational context annotations cannot carry.

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?

The essential information is front-loaded in the first two sentences, but every sentence is then repeated verbatim in French, roughly doubling length without adding meaning for an agent. The billing statement is also duplicated within the English half ('identical to the HTTP route' plus 'not billed (0 $)').

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 tool with annotations covering safety and no output schema, the description supplies return format (embedded base64 PDF), auth, scope, and billing — enough to call it correctly. It stops short of linking to prerequisite tools or clarifying the index-vs-deed distinction against acte_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 100% with a single documented 'id' parameter, so the schema already does the work. The description adds no format, source, or constraints for the id (e.g., where to obtain it), so 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 first sentence names a specific verb (GET/download) and resource (PDF of an index or a deed for your organization) and states the return encoding (embedded application/pdf, base64). Sibling differentiation is only implicit — acte_get and plan_get are never named, so an agent must infer that 'deed' here overlaps with acte_get.

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 implied through the resource description ('PDF of an index or a deed produced for your organization'), so the agent can infer this is the retrieval step after an index/acte exists. But there is no explicit when-to-use versus when-not, and no mention of what to call first (e.g., document_entries) or how this differs from acte_get.

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