Adds a root MovieScene event track to a Level Sequence, enabling event triggers during playback and returning save status and track details.
Adds a root event track (UMovieSceneEventTrack) to a Level Sequence.
Returns: { sequence_name: string, track_class: string, section_count: int, saved: bool, save_error?: string }
| Name | Required | Description | Default |
|---|---|---|---|
| sequence_name | Yes | Name of the target Level Sequence. |
Changes observed during successful MCP inspections.
v1.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare the safety profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false), so the description doesn't need to re-state that it mutates. It does add useful behavior beyond the annotations by disclosing the return shape, notably saved and save_error, which tells the agent the operation persists the asset and can report save failures. It says nothing about failure modes when sequence_name is invalid.
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 short lines, front-loaded with the action, and the return-value block is a reasonable substitute since no output schema is declared. It is tight, though the inline return signature is slightly awkward as prose.
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 single-parameter mutation with a non-destructive annotation profile, the description covers the action and the returned fields, compensating for the absent output schema. It would be fully complete with a note on what happens when the target sequence does not exist or is not open.
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?
Only one parameter with 100% schema description coverage, so the schema already documents sequence_name. The description implies the sequence context but adds no extra semantics such as accepted name forms or whether the sequence must be loaded. Baseline 3 is appropriate.
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 ('Adds a root event track ... to a Level Sequence') and even names the underlying class (UMovieSceneEventTrack), which lets an agent distinguish it from track-section siblings like add_event_track_section. It stops short of explicitly contrasting itself with the many other add_*_track tools in the sibling list.
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?
There is no guidance on when to use this versus alternatives such as add_event_track_section, add_notify_track, or add_anim_bone_track, and no stated prerequisites (e.g. whether the sequence must already exist or be open). The agent must infer the entire usage context from the name.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.