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

Annotations are empty, so the description carries the full burden. It discloses that the operation is asynchronous, returns a `tool_job` id and `queued` status, requires polling, is free with size/duration limits, and that calling `complete_upload` would incorrectly trigger the paid pipeline. This goes well beyond the bare schema.

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?

The description is longer than average, but each paragraph earns its place: core conversion purpose, upload workflow and exclusion of `complete_upload`, gif-only parameters, and async polling behavior. It is organized and free of fluff, though it could be tightened slightly.

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?

Even with no output schema and no annotations, the description fully equips the agent: it explains where `file` comes from, that `complete_upload` must NOT be called, how to obtain gif-specific parameters, the async polling flow with `get_tool_job_status`, and rate-limit behavior. Nothing critical is missing for a correct invocation.

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 schema already documents all four parameters with 100% coverage, so the baseline is 3. The description adds valuable context beyond the schema: `file` must be an uploaded video id from `create_upload` or `list_videos`, `complete_upload` must not be called, and `fps`/`width` apply only to gif output. This is useful, though the schema already covered the core meanings.

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 description opens with a specific verb and object: converting an uploaded video file into a target format. It enumerates supported formatsretically and distinguishes this from upload and paid pipelines by naming `complete_upload` as something to avoid, which helps disambiguate from sibling tools like `edit_video` and `extract_thumbnails`.

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 explicitly tells the agent how to supply input: use the hashid from `create_upload` or `list_videos`, do not call `complete_upload`, and provides the exact upload workflow (`PUT` bytes to the returned URL before calling this tool). It also directs the agent to poll `get_tool_job_status` for the result, so follow-up behavior is unambiguous.

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