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 fully covered without the text. The description does contribute the useful contrast that this returns full text plus a citable URL and metadata rather than a search snippet, but it says nothing about truncation, very large documents, or behavior on an id that resolves to nothing.

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 front-loaded: the first establishes what is returned and that the URL must be cited, the second handles the single parameter. Dense but no filler; the parenthetical list of document types is long yet it is the sentence that lets the agent recognize what it is fetching.

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 one parameter, full schema coverage, an output schema and complete annotations, the only burden left on the description is purpose, provenance of the id, and what kind of result to expect. All three are stated, and the citation requirement for readers of the text is a detail no structured field carries.

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 percent, so the baseline is 3, and the description earns the extra point by giving concrete accepted forms: a path such as « /forfaits/pro » or « /zones-frontalieres/genevois », or a full comontel.fr URL. That is genuinely more actionable than the schema's one-line description of the same field.

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 a specific verb and resource: returns the full text of a document previously found with search, along with its citable URL and metadata. It explicitly enumerates the document types (plan, border-zone page, comparison, guide, FAQ, glossary term, theme) and names its sibling search as the source, so an agent can tell it apart from search and from the type-specific getters.

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 prerequisite workflow is made explicit in both directions: search produces the id, and fetch consumes it. What is missing is differentiation from sibling getters such as get_faq, get_guide and get_plan, which appear to retrieve the same families of content; the description does not say when fetch is preferable to those or that those return structured extracts rather than full text.

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