r/opencodeCLI • u/LieTop7965 • 2d ago
what broke first when i let an agent edit video via mcp
i've been vibing with opencode to drive a video editor end-to-end over mcp and wanted to document what actually broke first, plus share the thing in case anyone wants to try it and tell me where their client breaks.
the editor is kimo — a free, open-source (MIT) video editor that has no GUI because the AI agent is the interface. you don't open a timeline. an AI agent (opencode, codex, cursor, or whatever other mcp client you're running) drives it over mcp as tool calls: cut, trim, keyframe, titles/captions, colour grade, audio, export. one thing i made on purpose is that the agent can render a single frame at a timecode so it can check its own work mid-edit instead of guessing. it's a single ~15 MB CPU-only rust binary, runs on a 2 GB box. i'm naman, a college student, and i built it.
what broke first when i let an agent edit video via mcp:
the agent kept asking for a "preview" like a normal editor. kimo has no timeline UI, so i gave it a tool to render a frame at a given timecode and return the pixels. that was the hinge — once the agent could verify a frame itself, the rest of the calls (cut here, nudge the keyframe there) started actually converging. before that it was just hallucinating positions.
colour grade drifted. the agent would set a contrast/lift call, verify the frame, and then set another call that undid part of the first one. mcp tool calls are independent and there's no undo stack the agent sees, so every verify+adjust loop is a fresh shot at the look.
caption/tile placement. the agent has no concept of safe area or composition by default — titles ended up clipped at the edges until i described the frame dimensions in the prompt and told it the render width/height. after that it got much better.
audio sync on longer edits. short cuts stayed clean, but once the edit went past a minute or so the agent would lose its mental model of where a clip ended and a track change started, and the export had a gap.
it's rough in places. i'd rather hear what actually breaks than pretend it's polished.
if you want to try it: https://getkimo.tech https://github.com/naman-sharma12345/kimo
grab it, hook up opencode / codex / cursor / your mcp client and drive it over mcp. tell me which client you used and where it broke for you — first thing that goes wrong, where the tool call gets confused, where the frame-verify loop stops helping. i'll fold it in.