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Video craft — the concept gate and the seam rules

Video craft — the concept gate and the seam rules

The rules every video style shares. Before building, a concept gate: name what a reference clip does rather than what is in it, write the message line, propose three concepts, and get a storyboard approved in which every frame says why it means its line. While building, the seam rules: the same axis, direction and speed across every cut, one main direction for the film, an object carrying the eye, cause and effect, and no ambient drift passed off as motion. Adapted from HeyGen's HyperFrames.

Updated 14 October 2026 · By Sadeq

When to use it

The rules every video style shares, in two halves. Before building: the concept gate — name what a reference clip does rather than what is in it, propose three concepts, and get a storyboard approved in which every frame says why it means its line. While building: the seam rules — every cut keeps the motion's direction and speed, the film has one main direction, an object carries the eye across the cut, each move is caused by the one before, and ambient drift never counts as something happening. Use before building any video in a style skill (paper studio, terminal, dark glass, grain and map, brush stroke, poster motion), when someone shares a clip and asks for "something like this", and when a cut feels like a stack of slides. The style skill decides what the video looks like; this decides what it says and how it moves. Adapted from HeyGen's open-source HyperFrames skills (Apache License 2.0).

Complete file

SKILL.md

---
name: video-craft
description: >
  The rules every video style shares, in two halves. Before building: the
  concept gate — name what a reference clip does rather than what is in
  it, propose three concepts, and get a storyboard approved in which every
  frame says why it means its line. While building: the seam rules — every
  cut keeps the motion's direction and speed, the film has one main
  direction, an object carries the eye across the cut, each move is caused
  by the one before, and ambient drift never counts as something
  happening. Use before building any video in a style skill (paper studio,
  terminal, dark glass, grain and map, brush stroke, poster motion), when
  someone shares a clip and asks for "something like this", and when a cut
  feels like a stack of slides. The style skill decides what the video
  looks like; this decides what it says and how it moves. Adapted from
  HeyGen's open-source HyperFrames skills (Apache License 2.0).
license: Apache-2.0
metadata:
  author: daena-digital
  version: "1.0"
---

# Video craft — the concept gate and the seam rules

A style skill says what a video looks like: the material, the palette, the
moves. This skill says what the video means and how it gets from one
picture to the next. It exists to stop two failures:

- **Copying the surface of a reference.** Given a clip to learn from, the
  easy thing is to rebuild its objects — its ball, its cube, even its words
  — and attach them to our lines. The result looks like the reference and
  says nothing, because the objects meant something in the reference and
  mean nothing in ours.
- **Scenes built one at a time.** Each scene enters, settles and stops,
  and the next starts from rest. The eye's momentum dies at every cut and
  the video reads as slides.

## Credit

Most of these rules are adapted from **HyperFrames**, HeyGen's open-source
framework for making video from HTML, and the agent skills that ship with it:
<https://github.com/heygen-com/hyperframes>, licensed under the Apache
License 2.0 (<https://www.apache.org/licenses/LICENSE-2.0>).

- The storyboard as a proposal with a *Why* for every frame, value before
  evidence, and the source test come from its story-spine reference
  (`skills/hyperframes-creative/references/story-spine.md`). The source
  test is quoted from it.
- The vector law, the main direction and the directions held in reserve,
  carriers, cause and effect, motion that performs instead of idle motion,
  and the pause before a climax come from its motion-doctrine skill
  (`.claude/skills/motion-doctrine/SKILL.md`).

Read at commit `6f90ca1` on 14 October 2026. What we changed: everything is
rewritten in our own words; the rules are tool-agnostic (HyperFrames states
them in terms of GSAP and its own verification scripts, which are not
included); the timings are given in frames at 30 fps; and the first half of
the concept gate — naming the reference's essence, listening with the
sound on, and proposing three concepts — is Daena Digital's own, added after
a cut copied a reference's objects instead of its idea.

## Part 1 — The concept gate

Nothing is built until a storyboard is approved. Each step is cheap; a
picture changed at the storyboard costs a minute, the same change after the
render costs an afternoon.

### 1. Name the essence of the reference

When there is a reference clip, write three sentences about it, none of
which names an object in it:

- **What the viewer feels.** Awe at control, calm, urgency, being let in on
  a secret.
- **The trick that produces the feeling.** One mechanism: nothing ever
  cuts, everything becomes the next thing; one picture is explored for
  thirty seconds; a new real source every second.
- **The one rule the clip obeys.** The thing that, broken once, would make
  it a different clip.

Example. A motion designer's reel in which a ball smears into a red field,
a full stop grows into the next background and a square extrudes into a
cube. The objects are not the essence. The essence: the viewer feels a
designer's total control; the trick is that every object turns into the
next frame; the rule is that nothing cuts. A video built from that essence
can contain no ball and no cube at all.

### 2. Watch it with the sound on

Most short reels are cut to music, and the cuts, pauses and hits come from
the track. Mark where the beats land and what happens on each. A clip cut to
a beat and rebuilt over a voice is a different film; say how the timing will
change instead of finding out at the render.

### 3. Write the message line

One sentence: "This video tells [audience] that [message]." The message
lands by the second beat. Everything after it is evidence for it: the
mechanism, the feature, the screens. Two checks on the finished beat list:
delete every evidence beat and the rest still states the message; delete
the message beats and the video stops working. If it still works, it was a
tour, not a story.

### 4. Propose three concepts

Each concept keeps the trick and the rule from step 1 and changes
everything else: the objects, the order, the picture that carries the
message. Write each as one sentence plus one sentence on why its main
picture means the message. The first idea that comes to mind is usually the
reference with our names swapped in; if one of the three is that, replace
it.

Example, for a marketing studio whose message is "one team does all of it",
keeping the reel's essence: a website wireframe folds into an ad, the ad
becomes an email, the email's button becomes a chart that rises, the chart
becomes the studio's name. One object the whole way through, because it is
one team the whole way through.

### 5. Storyboard the chosen concept as a proposal

Open with the message line, then one row per frame:

| Frame | Beat | On screen | Why |
|---|---|---|---|
| 01 | hook, 0–2 s, "Make it move." | The wireframe of a homepage draws itself and starts to fold | States the promise in the studio's own material |

**Why** is the frame's job in the story, traced back to the message line.
A frame whose why cannot be traced to the message is cut, not decorated.
Six frames is enough at this stage; show them as rough stills and wait for
"approved" or "change frame 3" before writing anything that renders.

### The two tests every picture passes

- **The source test.** "If the prop could appear unchanged in another
  product's video, it didn't come from the source." (HyperFrames,
  story-spine.) Swap it for something only this subject could produce: the
  client's own pages, words, process and numbers they can source.
- **The meaning test.** One sentence says why this picture means its line.
  "A cube for strategy" fails: nothing about a cube means strategy. "The
  wireframe folds into the ad it becomes" passes: it shows the same people
  doing both.

## Part 2 — The seam rules

### The vector law

How a picture leaves decides how the next one arrives.

1. **Axis.** Sideways stays sideways, vertical stays vertical, depth stays
   depth. Never trade axes across a cut.
2. **Direction.** The same way, never mirrored. In depth, the direction is
   whether things are growing or shrinking: a picture that recedes is
   answered by one that keeps receding, not by one that grows from small.
   That is the commonest mistake, because growing from small is the default
   entrance for almost everything.
3. **Speed.** The new picture starts at the speed the old one ended: ease
   in out of the old, ease out into the new, over the same distance and
   about the same number of frames.
4. **Mid-motion.** The cut lands while both sides are moving. Settling to
   rest before the cut, or starting from rest after it, is a dead beat.

A hard cut obeys the law too: the camera push or pan on both sides runs
the same way at the same speed. Where a style allows plain cuts on the beat
(a montage), it says so, and the law is suspended only there.

### One main direction

Pick one direction for the film's ordinary cuts and keep it. Every other
direction is held in reserve and means something when it is spent:

| Direction | Means |
|---|---|
| The main direction | Next beat: ordinary progress |
| Upward | A conclusion rising above what came before |
| Into depth | Going deeper into the same thought |
| Out of depth, something large arriving | An arrival: the bigger thing lands |
| Bursting past the camera | Leaving one world for another |

Never run two cuts in a row in opposite directions; it reads as an error.
A change of direction needs a visible cause (a click, an impact, a bounce)
or a chapter break.

**Write a cut list before building**: one row per cut, with its frame, the
exit's axis and direction, the entry's, and what carries it. If a row does
not match, fix the plan, not the easing.

### Carriers

The eye follows objects. The strongest cut hands a real object across at
the same place and speed: a cursor in mid-path, a container that shrinks
into its slot in the next layout, a mark that flies to where it belongs, a
full stop that grows into the next background. With no natural carrier,
let the main element of the old picture travel part of the way out while
the new one arrives already moving. Never a crossfade: it carries nothing.

### Cause and effect

Each move is set off by the one before: click, squash, release, flight,
impact, recoil, reveal.

- The effect starts on the frame of its cause, never a few frames after.
- Big things react slowly and small things snap.
- A force is what allows a change of direction; a flip with no cause reads
  as a mistake.

### Motion that performs

Ambient motion — a drifting field, a slow tilt, a pulse, a glow that
breathes — is atmosphere. It never counts as the change a clause needs.
Between its entrance and its exit, every scene is doing one named thing:

- **Staged reveals**: content held back and paid out on the words.
- **The camera with intent**: wide, then travelling, then arriving on the
  subject.
- **The product behaving**: progress advancing, a list filling, a number
  the script says ticking up.
- **Elements acting out the line**: a card filed into a stack, an item
  dragged, a result assembling.
- **A cursor leading to a click** that sets off the next beat.

A scene that has finished entering with seconds left needs more story, not
more drift. The test: pause on any frame and something meaningful is
mid-flight.

### The pause before the climax

The one deliberate stillness: 10–20 frames between the biggest action and
its result — the click and the reveal, the last line and the name — so the
result lands. Once or twice a video, planned in the storyboard, never a
scene that ran out of things to do.

## Review before export

- [ ] The reference's essence is written in three sentences that name no
      object in it.
- [ ] Three concepts were offered, and the storyboard was approved before
      anything was rendered.
- [ ] Every frame's why traces to the message line.
- [ ] Every picture passes the source test and the meaning test.
- [ ] The cut list exists; no two cuts in a row run in opposite
      directions, and every change of direction has a cause.
- [ ] Every cut lands mid-motion on both sides; no crossfades.
- [ ] Paused on any frame, something meaningful is mid-flight, and drift
      is not it.

Sources

What this is based on

Apache-2.0 — Adapted from the agent skills that ship with HyperFrames, HeyGen's open-source HTML-to-video framework (github.com/heygen-com/hyperframes), licensed under the Apache License 2.0: the story-spine reference and the motion-doctrine skill, read at commit 6f90ca1 on 14 October 2026. Rewritten in our own words and made tool-agnostic; the first half of the concept gate (the reference's essence, listening with the sound on, three concepts) is Daena Digital's own.