timeline_create_compound_clip

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions the merging behavior but does not state whether the original items are replaced, whether the operation is reversible, any required permissions, or potential side effects. This is a significant gap for a mutation 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?

The description is exactly two sentences. The first sentence states the action, and the second clarifies the concept. There is no fluff or repetition, and it is front-loaded with the key action.

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?

The tool has moderate complexity and no annotations. While the schema fully documents parameters, the description omits important operational context such as whether items need to be contiguous, whether the timeline is destructively modified, and what the output schema returns. The presence of an output schema helps, but behavioral prerequisites and side effects are still unclear.

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?

The input schema covers 100% of parameters with descriptions, so the baseline is 3. The description does not add extra meaning beyond the schema; it only mentions 'specific track' which aligns with the track_type and track_index parameters but adds no additional semantic detail.

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?

The description clearly states the tool's function with a specific verb and resource: 'Create a compound clip from timeline items on a specific track.' It also adds an explanatory second sentence ('A compound clip merges multiple timeline items into one editable unit') that reinforces the purpose and distinguishes this from other timeline tools like timeline_create_fusion_clip.

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 description implies usage when you want to merge timeline items into an editable unit, but it does not explicitly state when to use this tool over alternatives or provide exclusion criteria. It gives clear context without naming any alternatives, so it earns a middle score.

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