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

Annotations only cover safety (readOnlyHint=false, destructiveHint=false, openWorldHint=false); the description adds non-obvious behavior: no coin cost, an account-tier gate on quality/format rungs, and a daily export allowance (a rate limit). It also discloses the asynchronous nature by pointing to get_export for polling, though it doesn't cover failure/cancel behavior.

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 tight sentences: what is queued, the cost/allowance constraint, and the retrieval step. Front-loaded action statement with zero filler, and each sentence carries distinct information.

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?

With no output schema, the description correctly supplies the retrieval path (poll get_export) and the resource constraints an agent needs before queuing. The only minor gap is that it never states what this call returns (e.g. the export/job identifier to pass to get_export).

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 fit, format, quality, aspect_ratio and aspect_ratios including defaults and the 'at most 4' cap. The description's 'one export per aspect ratio' merely echoes the schema's own wording, adding no new syntax or interpretation. Baseline 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?

Specific verb+resource: 'Queue a render of a cut to a video file', with the multiplicity rule ('one export per aspect ratio') stated up front. It is clearly distinguishable from the read-only sibling get_export (which it names as the polling counterpart) and from get_cut/list_cuts.

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?

Provides strong context for when this is appropriate ('Rendering spends no coins', allowance applies) and explicitly routes the agent to the follow-up tool: 'Poll get_export for the file.' It stops short of naming alternative tools or stating exclusions/preconditions (e.g. when to prefer generate or upscale instead).

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