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

Annotations already declare idempotentHint=true, destructiveHint=false, and readOnlyHint=false, so the safety profile is covered. The description adds genuinely non-structured behavior: the call is asynchronous and returns immediately despite being a write operation, and the output lands in get_job under a 'translations' key, plus the note that subtitle timecodes are preserved. Rate limits, credit cost, and failure modes are not mentioned.

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 tight sentences. The capability comes first, then the result-retrieval hint, with the useful 'timecodes kept' parenthetical folded in rather than padding. Nothing is wasted or restated from 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 no output schema, the description correctly fills the gap by explaining that the call returns immediately and where the translation surfaces (get_job → translations). The 'completed job' precondition and source prerequisites are covered. Minor omissions: no mention of cost/credit implications or behavior when the target language or source artifact is unavailable.

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%, so every parameter including the source enum and its default are already documented in structured data, making 3 the correct baseline. The description's mention of which sources exist and that timecodes are kept marginally reinforces the 'srt/vtt/timed' enum semantics, but adds no new syntax or constraints.

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 (translate) and enumerates the exact resources it operates on (transcript, subtitles, summary, action items) constrained to 'a completed job'. This is unambiguous and clearly distinct from sibling tools like request_summary, get_job, or start_transcription.

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?

'Of a completed job' establishes the precondition for invocation, and the closing sentence routes the agent to get_job to retrieve the result, which is a clear next-step pointer. It stops short of stating exclusions (e.g., that summary/action_items must already exist is left to the schema, and no alternative tool is named for pre-completion cases).

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