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

Annotations only declare the basic safety profile (readOnlyHint=false, destructiveHint=false), so the description carries real weight here and delivers: async execution with an immediate task_id, a chat message on completion/failure, plan-quota consumption, and a reuse-without-spend path. The only nit is that the duplicate-call reuse behavior reads as idempotent while idempotentHint=false, though the first invocation does still spawn a task, so it is not a true contradiction.

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?

Front-loaded with the outcome (new inactive copy) and then layered by importance: async behavior, cost, reuse, language list, follow-up, error codes. Dense and information-rich, but on the long side; the language enumeration and error list could be trimmed or deferred to the schema.

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 an output schema present, the description need not describe return values, and it still covers everything an agent needs: side effects (new copy, quota spend), async contract, dedupe behavior, the follow-up parameter's downstream effect, and the full failure surface. 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?

The description enumerates the twelve accepted target_language codes, which is useful guidance, and explains follow_up_instruction's purpose and one-tap delivery ('the ready message offers it on the new copy'). It slightly tightens the schema's looser claim that bare language codes or English names like 'German' are accepted, but the semantics added are net positive.

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 opening sentence states a specific verb (translate), resource (resume), and the exact resulting artifact ('a NEW inactive copy named after the language'), and explicitly distinguishes the operation from in-place edits ('the original resume is not changed'). This separates it cleanly from siblings like create_resume_version or rename_resume without opening their schemas.

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?

It states when to use it, routes progress checks to the named sibling get_task_status(task_id), defines the dedupe path ('if this resume was already translated into that language, returns the existing copy... spends nothing'), and covers the follow-up case where the user asked for more than translation. Explicit error semantics (already_in_language, limit_exceeded) further define when the call is valid.

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