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

Annotations already declare readOnlyHint=false, destructiveHint=false, idempotentHint=false, and openWorldHint=true, so the safety and world-access profile is covered by structured data. The description adds nothing beyond that: it does not say whether the call is asynchronous and returns a job_id, whether it consumes credits, or what happens to the source 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?

A single front-loaded sentence with no filler, so nothing needs trimming. It is arguably under-sized for the tool's complexity, but the wording itself is efficient and clear.

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 an asynchronous, credit-consuming transformation tool with a chaining input and no output schema, the description should say what the call returns, such as a job_id to poll with get_job, and how the two mutually exclusive source inputs are chosen. None of that is present, leaving the definition noticeably thin relative to the tool's complexity.

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 all three parameters, including the source_id/video_url mutual-exclusion and the job-chaining behavior, are already fully documented in the schema. The description's format list merely repeats the enum values and adds no new meaning, so the baseline of 3 applies.

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?

States a specific verb and resource: converts a video to another format, and enumerates the supported formats. It does not differentiate itself from siblings such as compress_video, resize_video, or reframe_video, but an agent can still tell what the tool does from the sentence alone.

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?

There is no guidance on when to use this tool versus the many sibling video-transformation tools, and no mention of prerequisites such as credits or an existing job to chain from. The when-to-use context exists only implicitly in the name.

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