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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is covered. The description adds genuinely useful context beyond them: the required jobs:read scope, mandatory Bearer API key in the Authorization header, and explicit zero-cost billing behavior — all things an agent cannot infer from the schema or annotations.

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 route and purpose are front-loaded, which is good, but every sentence is duplicated in French, roughly doubling the length with no new information for an English-reading agent. 'Billing: identical to the HTTP route' followed by 'is not billed (0 $)' is also redundant restatement.

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 rich annotations and no output schema, the definition covers auth, scope, cost, and the nature of the returned data ('parsed lines'). It stops short of describing entry structure, ordering, or pagination, but nothing critical to invoking the tool correctly is missing.

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?

Only one parameter exists and schema coverage is 100% ('Document id.'), so the schema already does the work. The description implies via the route that the id identifies the index document, but adds no format, source, or disambiguation details beyond that implication.

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 the concrete operation and resource: 'Stored parsed lines of one index document', reinforced by the HTTP route GET /v1/documents/{id}/entries. An agent can tell this returns entry lines rather than document metadata (document_get) or job output (job_results), though the description never explicitly contrasts itself with those siblings.

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?

There is no statement of when to call this versus alternatives such as document_get, registre_index_request, or job_results. The only contextual hints are the jobs:read scope and the 'not billed' note, which are operational facts rather than selection guidance.

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