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

The description adds important behavioral context beyond annotations: it discloses that the operation is a background job, costs credits, and returns a project id to be used with wait_for_video_project. It also notes the v1/v2-only preset limitation. With annotations already covering safety (readOnlyHint=false, destructiveHint=false), this extra context is valuable, though it doesn't detail credit amounts or consequences for the original video.

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 two sentences and front-loads the core action, followed by key constraints (version support, background job, cost, follow-up tool). Every sentence contributes useful information without redundancy.

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?

Given the tool's complexity (nested objects, six parameters) and the presence of an output schema, the description covers the essential context: async behavior, cost, and the follow-up wait tool. It doesn't explain the fps_resolution trade-off or asset sourcing, but those are well documented in the schema, so the description is nearly complete for an agent to call it correctly.

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 high (83%), so the schema already documents most parameters in detail. The description mentions art-style presets and custom prompts, which loosely maps to the style object, but adds no further syntax or constraints beyond what the schema provides. A baseline 3 is appropriate.

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 states a specific verb and resource: 'Restyles an existing video clip with an art-style preset or a custom prompt.' It names the supported preset versions and explicitly excludes v3, which helps an agent distinguish this from sibling tools like edit_video or translate_video.

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 clearly states that the tool starts a background job, costs credits, and returns a project id for wait_for_video_project, giving the agent essential follow-up guidance. However, it doesn't explicitly compare against alternative sibling tools (e.g., edit_video or upscale_video) or state when-not to use this tool beyond the v3 limitation.

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