set_transition

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 valuable non-obvious side effect: the timeline shortens by duration_s. However, it omits permission requirements, overwrite/idempotency behavior, error conditions for non-adjacent clips, and the fact that a style parameter (defaulting to 'luma') can change the visual result entirely.

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?

Two tight sentences with zero waste: the core operation and its side effect are front-loaded. Every clause carries 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?

This is a mutation tool with no annotations, no output schema, and zero parameter documentation, yet the description covers only the core mechanic. An agent still lacks the style value set, adjacency failure behavior, and whether an existing transition is replaced — gaps an agent needs before invoking it safely.

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 5 parameters, so the description must compensate. It only explains duration_s (via its timeline-shortening effect) and implies from/to through 'between two ADJACENT clips'; style and project_name are entirely undocumented, and no valid style values are given.

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 (a crossfade transition between two clips) and clarifies it is both a video dissolve and an audio mix, which distinguishes it from clip-editing siblings like trim_clip or split_clip. It does not explicitly name or route against any sibling tool, keeping it 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?

Usage is implied through the 'ADJACENT clips' precondition and the note that the timeline shortens, which tells an agent this is a timeline-altering edit. There is no explicit when-to-use vs. alternative guidance, no statement about what happens if clips are not adjacent, and no mention of replacing an existing transition.

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