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

Annotations only carry idempotentHint=true, so the description adds meaningful disclosure beyond them: what is preserved (doc_id, title, project, tags), that the text is fully replaced, and the side effect that chunks are reindexed. It stops short of noting permissions or failure modes, but the behavioral picture is substantially richer than the annotation.

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 tightly packed sentences with zero waste: the first states scope and preservation/reindexing behavior, the second states the calling precondition. Front-loaded and efficient.

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 two-parameter mutation tool that ships an output schema, everything an agent needs is present: replacement semantics, preserved fields, the reindexing side effect, and a strict invocation rule. Nothing material 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?

Schema description coverage is 100% with only two parameters, so the schema already documents both text and doc_id. The description adds only a light constraint ('même doc_id', existing document) without new format or syntax detail, so the 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?

States a specific verb and resource ('Remplace le texte d'un document existant') and clarifies that it acts on an existing doc_id while preserving title, project and tags, which distinguishes it from the add_* siblings that add new content. An agent can tell it replaces the whole text rather than appending.

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?

Explicit and strict: 'N'appeler QUE si Denis le demande explicitement dans son message courant ; jamais de ta propre initiative.' This gives a clear when-to-use condition and an explicit prohibition, leaving nothing to inference.

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