# OTIO and XML Handoff to NLEs — effect skill for transitions

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Write the edit (clips, cuts, dissolves) as OpenTimelineIO and convert to XML so an editor can finish it in an NLE.

- **Type:** [Effect](https://varg.ai/how-to/effects.md) · [Transitions](https://varg.ai/how-to/browse/skills/transitions.md)
- **Slug:** `otio-fcpxml-handoff`
- **Status:** live
- **Publisher:** varg (varg, verified)
- **License:** MIT
- **Source:** https://github.com/vargHQ/skills/blob/main/varg-video-edit-library/references/transitions.md#otio-fcpxml-handoff
- **Works in:** Claude Code, Claude.ai, Codex, Cursor, OpenClaw, Gemini CLI, Any MCP client, varg Studio
- **Requires:** Python
- **Cost:** Free — the take renders locally; generated footage, if any, bills by the model

## What it does

An editable timeline in Resolve, Premiere or Final Cut with real cuts and dissolves instead of a flat render.

**When:** When a human editor will refine the agent's rough cut; agency and post-production handoffs.

**Watch out:** Assuming effects survive: only basic cuts and dissolves translate; designed transitions (whip, glitch, shader) do not.

**Timing:** Dissolves: in_offset/out_offset need handles in the source on both sides

**Also called:** OpenTimelineIO, FCPXML, FCP7 XML, Premiere handoff, Resolve import, EDL

### In Python

Python with opentimelineio 0.18 (tested). Transitions sit between clips and do not change the track length; offsets need media beyond the cut:
```python
import opentimelineio as otio
RATE = 30
rt = lambda s: otio.opentime.RationalTime(round(s * RATE), RATE)
def clip(path, src_in, dur, media_dur):
    return otio.schema.Clip(name=path,
        media_reference=otio.schema.ExternalReference(target_url=path,
            available_range=otio.opentime.TimeRange(rt(0), rt(media_dur))),
        source_range=otio.opentime.TimeRange(rt(src_in), rt(dur)))
tl = otio.schema.Timeline(name='edit')
v = otio.schema.Track(name='V1', kind=otio.schema.TrackKind.Video); tl.tracks.append(v)
v.append(clip('a.mp4', 0, 5, 10))
v.append(otio.schema.Transition(transition_type=otio.schema.TransitionTypes.SMPTE_Dissolve,
                                in_offset=rt(0.25), out_offset=rt(0.25)))
v.append(clip('b.mp4', 1, 4, 10))
otio.adapters.write_to_file(tl, 'edit.otio')                          # Resolve 18.5+, Premiere 25.6+
otio.adapters.write_to_file(tl, 'edit.xml', adapter_name='fcp_xml')   # pip install otio-fcp-adapter
```
In the test the FCP7 XML kept the dissolve (`<transitionitem>` with `Cross Dissolve`), while `otio-fcpx-xml-adapter` (`fcpx_xml`) wrote the clips but dropped the transition. The FCP XML adapter also needs `available_range` on every media reference. CLI: `otioconvert -i edit.otio -o edit.xml -O fcp_xml`. Remotion projects can use the `remotion-opentimeline` agent skill (Remotion transitions are not exported as OTIO transitions).

### Where this comes from

- [OpenTimelineIO: timeline structure (Transition)](https://opentimelineio.readthedocs.io/en/latest/tutorials/otio-timeline-structure.html)
- [Remotion: export to OpenTimelineIO](https://www.remotion.dev/docs/export-opentimeline)

## Use when

- When a human editor will refine the agent's rough cut; agency and post-production handoffs.

## Not for

- Assuming effects survive: only basic cuts and dissolves translate; designed transitions (whip, glitch, shader) do not.

## Install

- Claude Code: `claude plugin marketplace add vargHQ/skills && claude plugin install varg@varg`
- Codex: `npx skills add vargHQ/skills --skill varg-video-edit-library -a codex -y`
- Cursor: `npx skills add vargHQ/skills --skill varg-video-edit-library -a cursor -y`

## Example output

https://s3.varg.ai/how-to/previews/bba707dad9b3/take-otio-fcpxml-handoff.mp4 — dissolve between two shots, with the timeline strip of the edit. Footage: Tears of Steel (2012), (CC) Blender Foundation | mango.blender.org, CC BY 3.0; Coffee Run (2020), Blender Studio | studio.blender.org, CC BY 4.0. (credit: Rendered by varg · Tears of Steel (2012) + Coffee Run (2020))

## More transitions skills

- [editly](https://varg.ai/how-to/skills/editly.md): Declarative JSON5 video editing CLI/API: clips, titles, transitions, audio mixing, rendered with ffmpeg.
- [Mix (Cross Dissolve)](https://varg.ai/how-to/skills/mix-dissolve.md): The two shots blend through each other. The quietest transition: "time passes" or "this continues".
- [Dip to Black](https://varg.ai/how-to/skills/black-fade.md): A fades to black, then B fades up. Marks the end of a section or a bigger jump in time.
- [White Flash](https://varg.ai/how-to/skills/white-flash.md): The frame blows out to white for a moment and opens on the next shot. Energy, memory or a camera snap.
- [Pull In (Zoom In)](https://varg.ai/how-to/skills/pull-in-zoom.md): The camera rushes into shot A and lands, still moving forward, in shot B. The signature short-form transition.
- [Pull Out (Zoom Out)](https://varg.ai/how-to/skills/pull-out-zoom.md): The camera jerks backwards out of shot A and keeps pulling back as shot B settles in.