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

Annotations already indicate non-readonly and idempotent behavior. The description adds valuable behavioral context: the API verifies the object actually landed in storage before moving the asset from processing to ready. It also highlights the consequence of not calling the tool, which is meaningful beyond the structured annotations.

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 sentences, each earning its place: what the tool does, the critical timing, and the exception for video uploads. No filler or redundant restatement of the tool name. The description is front-loaded with the action and then provides essential context.

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?

The description fully covers the typical invocation context: it references the related upload tool, states the required ordering, explains storage verification, and clarifies when the tool is unnecessary. With an output schema present and complete parameter schemas, nothing essential for an agent to invoke correctly 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?

Input schema coverage is 100% and both parameters already have clear descriptions. The tool description adds workflow context around media_asset_id by referencing clipform_upload_media_asset, but it does not materially expand parameter semantics beyond the schema, so the 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 precise action—confirming completion of a signed-PUT still image upload—and identifies the exact resource and preceding step. It clearly differentiates this from clipform_upload_media_asset and from video upload flows, so an agent knows what this tool is for and what it is not.

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 explicitly says to call this 'right after the PUT succeeds' and warns that the asset remains invisible if skipped. It also explicitly excludes video uploads, saying they settle automatically via TUS/Mux. This gives clear when-to-use and when-not-to-use guidance relative to alternatives.

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