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Asset Import
This build runs the editor and its media server locally. There is no hosted import API, no CLI, and no OAuth: media enters the project through the editor UI or through the agent tools below. Pick the path by where the bytes live.
Path 1 — user's local files (primary)
Ask the user to drag the files into the editor (preview canvas or 我的素材 panel) or use the upload button. The local pipeline then runs automatically: streaming write to /media/uploads/, conditional transcode (≤1920 long edge, browser-friendly codec, ~8Mbps), audio extraction, and auto-transcription (ASR starts on upload). Do not ask the user to pre-convert, pre-trim, or transcode anything themselves — the pipeline handles it.
The agent cannot read the user's filesystem. If the user gives you a /Users/... or C:\... path, tell them to drop that file into the editor instead; you cannot fetch it.
Path 2 — public URLs (agent-driven)
Use download_media with up to 4 URLs per call. The server fetches, stores under /media/uploads/, and registers pool assets. Prefer this for stock/web media the user pointed at. After download, the asset behaves exactly like an upload (same transcode/ASR pipeline).
Path 3 — placeholder before bytes (timeline-first work)
Call import_media with {"action":"register_placeholder"} to mint a deterministic assetId and pool row before bytes exist. Use it when you want to lay out the timeline (edit_item etc.) while an upload is still in flight; the asset relinks automatically when bytes land. Report progress precisely: once the placeholder is registered say the assetId is known; while bytes are still uploading say so — never claim a file is ready before track_progress (target=upload) confirms it.
import_media with {"action":"create_session"} returns local direct-upload endpoints (POST /upload?name=...&assetId=...). This is for host-side scripts the user runs in their own terminal (e.g. curl -T file '/upload?...' against the dev server); the agent sandbox cannot reach localhost, so do not try to upload from run_code.
Editing discipline
For multi-source edits, build reviewable work from original source assets in the OpenChatCut timeline. Do not locally concatenate, pre-trim, pre-compose, burn captions, or flatten media before import — import originals and do all composition on the timeline so every step stays reviewable and undoable.
For code assets such as hand-authored Motion Graphics, use the create-motion-graphics skill (create_motion_graphic_from_code for new assets, asset-code updates for edits) — MG code is not an imported file.
Storage notes
- Bytes live on the local disk (
/media/uploads/), served directly with Range support. If Cloudflare R2 is configured, uploads mirror to R2 and other devices can hydrate from it; without R2 the project is local-only. - Local-only is a valid end state: preview, editing, and export all read from disk. Cloud mirroring is only needed for cross-device access.