Edit 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 a real behavioral trait beyond the schema: the operation SPENDS CREDITS, uses a costlier model, and the quote is checked against max_credits. However, it omits mutation semantics (does editing alter or replace the source clip?), permission/auth needs, and response behavior, leaving meaningful gaps for a credit-spending write tool.

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 short sentences, front-loaded with the core action and then the cost caveat; essentially no filler. The only minor inefficiency is restating the max_credits check that the schema already explains.

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 9-parameter, credit-spending mutation with no annotations and no output schema, the description covers cost but leaves most parameters (character_ids, aspect, resolution, wait, dry_run) and the edit-vs-generate routing unexplained. An agent would still guess at invocation details.

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 coverage is only 33%, so the description should compensate, but it clarifies only 'prompt' (as 'instruction') and restates max_credits, which the schema already documents. It adds no meaning for character_ids, aspect, resolution, wait, or dry_run, which together represent most of the undocumented surface.

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+resource ('edit an existing clip') and adds a distinguishing trait versus the sibling: it uses an Omni edit model that is costlier than generation, implicitly separating it from flow_generate_video. An agent can tell what the tool does without opening the schema, though the sibling is never named explicitly.

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?

The 'costlier than generation' note implies you should only edit when you already have a clip rather than generate, but it never explicitly names flow_generate_video or flow_video_status as alternatives, nor states the precondition (an existing media_id from a completed generation). Usage is implied rather than directed.

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