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

Annotations already declare non-destructive (destructiveHint=false) and idempotent (idempotentHint=true); the description adds genuinely non-obvious behavior: cue boundaries and timestamps are preserved, mispronunciations are deliberately left uncorrected, and proper nouns are protected. What is missing is whether it writes back into the existing cues in place (readOnlyHint=false implies mutation) or produces a new track/artifact.

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?

Three front-loaded sentences, each carrying a distinct fact (transformation, structural preservation, linguistic exception rules). No filler or restatement of the title.

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 mutating tool with no output schema, the agent still lacks the mutation shape: does it overwrite the job's cues or create a new version, and can it be re-run against its own output? The behavioral notes are useful but the write semantics are unstated.

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% with clear per-parameter descriptions for jobId and track (enum primary/secondary), so the schema carries the load. The description adds nothing about the parameters — e.g., whether track selects input, output, or both — so 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+resource+transformation: spoken Cantonese cue text → written Chinese. An agent can tell what the operation does. It does not name or contrast with the closest sibling, lunara_translate, which is the one plausible confusion for this tool.

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 description never says when to use this versus lunara_translate or where it sits in the pipeline (after transcription/segmentation?). The phrase 'cue text' only weakly implies cues must already exist. No prerequisites, ordering, or exclusions are given.

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