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

With no annotations, the description carries the full disclosure burden. It reveals the time-to-live, the allowed upload methods, the payload format, and the downstream dependency on upload_id. It does not mention authentication requirements or what happens after expiration, but the core behavior is transparently disclosed.

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 entire description is one efficient sentence. The core purpose and primary condition are front-loaded, followed by necessary operational details. No filler words or redundant explanations are present.

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 zero-parameter tool with no output schema, the description covers the full lifecycle: why to use it, what to do with the returned URL, how long it remains valid, and what to pass to the next tool. It does not explicitly list response field names, but references them naturally enough for an agent to use them 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?

The tool has zero parameters, so there is no parameter semantics to clarify in the schema. The description adds value by explaining the returned artifacts (upload_url and upload_id) and how they should be used, which is sufficient for this parameterless tool.

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 names a specific action ('Mint'), a precise resource ('short-lived signed URL for uploading a video directly'), and an explicit condition ('when you do not have a public video_url'). It clearly differentiates itself from create_submission by describing this tool as a prerequisite step in that workflow.

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 states when to use the tool: only when no public video_url exists. It also provides concrete usage steps, including the HTTP methods (POST/PUT), accepted payload formats (raw video or multipart 'video' field), the 15-minute expiry, and the requirement to pass upload_id to create_submission. This leaves little to inference.

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