generate_video

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

With no annotations, the description carries the full burden, and it does disclose three meaningful traits: the operation is asynchronous, a job record is persisted, and paid generation requires allow_paid=true. It still omits cost implications (max_cost_usd exists but is unexplained), what a failed/queued job looks like, and how the job is later retrieved via get_video_status.

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 compact sentences with the core operation front-loaded and no filler. Dense, though the model-specific constraint is packed into a sentence alongside the audio semantics, slightly blurring the focus.

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 11-parameter, no-output-schema, no-annotation mutation tool, the description leaves most of the surface unexplained. An agent cannot infer valid values for resolution, aspect_ratio, duration, model, or the cost guard from either the schema or the description.

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 0% across 11 parameters, so the description must compensate and largely fails. It explains only generate_audio, allow_paid, and a model-specific constraint (HeyGen Video 1), leaving prompt, duration, resolution, aspect_ratio, max_cost_usd, dry_run, filename, and output_dir entirely undocumented.

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 ('Inicia text-to-video') plus the async persistence behavior, so the agent knows exactly what is produced. It does not distinguish itself from siblings like animate_image (which also produces video) or generate_image, so it stops short of a 5.

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?

Gives real conditional guidance: generate_audio is optional and omission delegates to the provider, and allow_paid=true is a hard prerequisite for generation. However, it never says when to choose this over animate_image or generate_variations, nor when dry_run should be preferred.

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