You see the problem.
Your agent can’t.
Vellum is a visual feedback interface for AI-edited video. Pin time-coded notes onto any HyperFrames frame — your coding agent reads them back and makes the edits.
curl -fsSL https://tryvellum.vercel.app/install | shFast
Flexible
Reliable
- note-1 · 0:08.10 `features` — this card feels heavier than the others — tighten the padding (pin 50.0%, 30.0%)
- note-2 · 0:08.40 `features` — make this headline a touch bigger (pin 19.5%, 36.0%)
Hover or focus a pin — the matching line lights up in the file.
See the whole loop in fifty seconds.
Spot the flaw, pin it to the exact frame, type the note, and hand it to your agent — then watch it land the fix. The same review loop, start to finish.
You spot it instantly. Vellum keeps where and when.
Typed into a chat box, feedback loses where on the frame and when in the timeline. Vellum records composition time, the element under your cursor, and pin coordinates — then writes files your agent reads.
- 01
Review
Open the player, scrub to the moment, drop a pin or drag a region note onto the frame.
- 02
Persist
Notes land in notes/annotations.md — plus structured JSON and optional mix levels.
- 03
Hand off
Tell your agent: “Address my Vellum review notes.” It reads, edits, and verifies.
- note-1 · 0:02.40 `title` — Hold this a beat longer before the crossfade (pin 50.0%, 41.2%)
- note-2 · 0:08.10 `features` — “Reliable” lands late — bring this card in 0.5s earlier (pin 74.6%, 52.3%)
- note-3 · 0:13.90 `stat` — make this number count up instead of fading in (box 24.1 × 30.0%)
Your agent reads what you saw.
Every pin becomes a line in notes/annotations.md — time, scene, coordinates, target element, and your feedback. When you’re done reviewing, the agent:
- 01Reads notes/annotations.md — each note links time, scene, and DOM target.
- 02Optionally runs vellum-review to render each frame with the pins drawn on.
- 03Edits the composition, snapshots to verify, and reports back note by note.
Works with any agent that reads files. Vellum ships a Claude Code skill, so the handoff is one prompt away.
› Address my Vellum review notes.
● Read notes/annotations.md — 3 notes.
note-1 · held the title 0.4s before the crossfade
note-2 · brought the “Reliable” card in 0.5s earlier
note-3 · switched the stat to a count-up
✓ 3/3 addressed. Snapshotted to verify.
Binds 127.0.0.1. No CORS, path-traversal guards on the notes API.
Pure Node built-ins. The player uses your project’s HyperFrames runtime.
Never modifies your composition — iframe plus a transparent pin overlay.
Works on any HyperFrames project. Scenes come from data-start attributes.
Pin your first note.
curl -fsSL https://tryvellum.vercel.app/install | shor npm i -g vellum-hf
Requires a HyperFrames project and Node ≥ 18.
Other install paths — npm, clone, shadcn registry →