Move a media item on a track to a precise time position by specifying track index, item index, and position in seconds.
Set the position of a media item.
Args: position: New position in seconds.
| Name | Required | Description | Default |
|---|---|---|---|
| position | Yes | ||
| item_index | Yes | ||
| track_index | Yes |
Changes observed during successful MCP inspections.
v1.7.3Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations only include destructiveHint: false, indicating non-destructive. The description does not add any behavioral context beyond that, such as effects on the project timeline, snapping, or reversibility. For a mutation tool, this is insufficient.
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 extremely concise, with a single sentence and a brief args section. It is well-structured and front-loaded, with no wasted words.
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 tool with three required parameters and no output schema, the description is incomplete. It does not explain how to identify the target item (track and item indices), what 'position' refers to (start time), or any prerequisites. It is minimally adequate but leaves critical information to inference.
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 description explains the 'position' parameter (seconds) but provides no explanation for track_index or item_index, which are both required and undocumented in the schema. With 0% schema coverage, the description should compensate but only covers one of three parameters.
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 states a clear verb and resource: 'Set the position of a media item.' It is specific about the action but does not differentiate from other item setters like set_item_length or set_item_volume. The purpose is clear but could be more explicit about what 'position' means (start time).
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?
No guidance is provided on when to use this tool versus alternatives. It does not mention any context or exclusions. An agent would have to infer that this sets the item's start position, and there is no indication of when it's appropriate.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.