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

Annotations already mark this as non-read-only and non-idempotent; the description adds the prerequisite that a PUT to a presigned URL must happen first. It doesn't disclose what side effects completing the upload has (e.g., creating a media asset, validating the file), so transparency is adequate but not rich.

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?

One clear, front-loaded sentence with no filler. It conveys the action and the required prerequisite in the minimum possible space.

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 finalization step, the description gives the key context: it follows a presigned-URL upload. Combined with full schema coverage and an output schema, an agent has enough to call it correctly; only the exact effect of finalization is left unspecified.

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 the schema already documents all seven parameters. The description adds no parameter-level meaning, which is acceptable under the baseline for full schema coverage.

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 identifies a clear action (complete) applied to a specific resource (the upload process) and anchors it to a distinct stage: after uploading to a presigned URL. This separates it from lifecycle siblings such as media_upload_start and media_upload_file, though it doesn't detail what finalization actually involves.

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?

"After uploading to a presigned URL" gives an explicit timing condition for when the tool should be invoked. It doesn't name alternatives or exclusions, but the lifecycle sequencing makes the intended use clear.

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