viral-hook

Viral Hook

Prepends an extreme, no-dialogue ~4s hook to a user's video — an attention-grabbing event
that erupts into the user's own scene, with an optional designed title burned into the
lower third — then hard-cuts into the untouched clip.

generate_viral_hook does the whole render in one call and returns BOTH
the hook and the stitched final. This skill's job is the creative judgment the tool can't
make: read the scene, pick a hook action from the menu, and write a title.

Hook rules (govern what you WRITE as hook_action)

1. Certain to grab attention, fast. Extreme and unmissable inside ~2s — over plausibility
   or relevance to the video's topic.
2. Erupts into the user's OWN scene. Same person, location, lighting — the tool anchors
   on the best visual anchor frame: 0s when usable, otherwise the first detectable face frame.
   Describe the event entering THAT space, never a different setting.
3. Use the scene's real geometry. Enter through a doorway with depth, a wall behind the
   subject, headroom above.
4. No dialogue. Voice-free (only ambient / impact SFX) — don't write spoken lines into
   hook_action.

Hook super-category menu

Four super-categories. Rotate super-category per run on the same clip/session — without
rotation, regenerates collapse to vehicle / explosion / creature. Archetypes are starting
points, not a closed list; invent freely within the category.

A. Destructive intrusion — external force violently enters and damages the scene

Archetype	What happens	Scene affordance
Incoming vehicle	car / truck / bus smashes through a wall or doorway and barrels at camera	background depth or a back wall
Flash flood / wave	a wall bursts and water surges down toward camera	corridor / back wall
Structural collapse	ceiling / wall / shelf caves in, debris rains down	headroom / walls
Explosion / blast	fireball erupts behind them, shockwave + debris rush forward	a background surface
Creature attack	animal / monster lunges from off-frame or bursts in	open off-frame edge
Absurd intruder	dinosaur, elephant, UFO, giant hand enters behind them	background space
Natural disaster	tornado / meteor / lightning / sinkhole	exterior or large space

B. Physics anomaly — laws of physics break, photoreal; scene + subject stay, motion goes wrong

Archetype	What happens	Scene affordance
Gravity flips upward	subject, loose objects, and dust fall UP toward the ceiling	any indoor scene
Time freeze around subject	every other object holds mid-air while the subject keeps moving	scene with loose / moving objects
Magnetic pull from ceiling	hair, clothing, jewelry, small objects yank upward as if a ceiling magnet fired	indoor scene + loose props
Room rotates 90°	walls + floor rotate around the upright subject until "down" is now a wall	enclosed space, visible walls + floor
Object orbit	all small loose objects lift off and orbit the subject like a tornado	scene with props on surfaces
Inverted color flash	the scene briefly inverts to negative colors and back, like a glitch	any scene

C. Content-supersized — an element FROM the clip appears building-sized and crashes in

Pull the element from the scene reading (Step 2) — hero product, pet, drink, phone, logo.

Archetype	What happens	Source element
Giant hero product	the product being shown appears at 10× scale and smashes through the wall / ceiling	the product in the clip
Building-scale pet	the subject's pet appears at building height in the window / doorway	a pet in the clip
Giant drink	the cup / can / bottle becomes building-sized and tips over the room	a drink in the clip
Giant phone	the subject's phone scales up to fill the back wall, screen glowing	a phone in the clip
Giant logo	a brand mark on a wall / shirt / packaging grows to cover the back wall	any logo in the clip

D. Content-projectile — a relevant object FROM the clip flies at the subject at speed

Source from the scene reading.

Archetype	What happens	Source element
Hero-object slam	the product they're showing flies at high speed into their face	the hero product
Food / drink splash	their food or drink hurtles into them, splattering everywhere	food or drink in the clip
Swarm pelt	many copies of a small object (sneakers / pills / cans) pelt them like hail	a small repeating object
Prop whip	an object on a surface (mug, lamp, book) whips off and slams into them	any heavy prop visible

Title rules (when the user wants one)

• ≤7 words, ALL CAPS, one punchy line. Tie it to BOTH the hook action AND the clip's
  actual content. Example: giant-sneaker projectile + sneaker unboxing → "THIS DROP HITS DIFFERENT."
• Optional — omit for a title-free hook.
• Typography defaults to bold distressed display type with a thick black outline. The user
  may override via type_style (a free-form style string) or by pasting a brand.md — extract
  ONLY the typography directives (fonts, weights, treatments), ignore logos / palette / voice.
  Warn that thin / un-outlined styles may wobble over the 4s.

Workflow

Step 0 — Intake (empty args)

If no video was provided, print this menu verbatim and STOP — do not call any tool:

What would you like a viral hook on? Paste any of:

• A local video path — e.g. /Users/me/Desktop/clip.mp4
• An https URL to an mp4
• A path + a title — e.g. clip.mp4 — "YOUR PROMPTS WON'T SAVE YOU"
• A path + "surprise me" — agent picks the hook action and title

Wait for the next message. Don't guess an input.

Step 1 — Get a URL

If the input is a local file, upload_asset it and use the returned
public_url. If it's already an https URL, use it directly. Any format is fine — no
transcoding or probing here.

Step 2 — Read the scene

analyze_media(video_url) → capture the subject + framing, indoor/outdoor + setting,
lighting, photoreal vs stylized aesthetic, and the spirit/topic. Also note the hero
objects (product, pet, drink, phone, logos), including whether each one is visible near the
opening or only appears later — required for super-categories C and D. This reading is passed
verbatim as the scene parameter.

Step 3 — Pick the hook action

Rotate super-category vs the previous run on this clip; pick a different one if possible.
Choose the strongest archetype the scene's geometry supports (A/B) or the most prominent hero
object (C/D). Write the specific hook action — entry vector + motion + scale + peak — as one
vivid sentence. This is hook_action. For C/D, name the exact hero object so the tool ties
it to the clip. If the hero object appears later in the clip rather than near the opening,
make the first hook frame explicit: "from the first frame, the subject is holding/using
[hero object]".

Step 4 — Title + style

Ask whether the user wants a title. If yes, propose a ≤7-word ALL-CAPS line tying the hook
action to the topic, get approval, and offer typography choices before rendering: default,
custom direction, or brand.md. If the user has no preference, use default and say so. If no
title is wanted, skip — the hook renders title-free.

Step 5 — Render

Call generate_viral_hook({ video_url, scene, hook_action, title?, type_style? }).
If it returns {task_id, status}, poll task_status(task_id) in a tight
loop until terminal, then read the result. On failed, surface the error — don't retry blindly.

Step 6 — Deliver

Present both clips:

• hook only: [[video:<hook_url>]]
• final stitched: [[video:<final_url>]]

What NOT to do

• Don't re-implement the render in the skill. No extract_frame / generate_image /
  edit_concat / transcode here — generate_viral_hook owns all of it. If the hook looks
  wrong, change the hook_action / title text, not the pipeline.
• Don't pass a seed. Variations should come from hook_action, title, or type_style.
• Don't bake a title onto the real video. The title belongs only on the hook.
• Don't auto-edit an approved title. If a rephrase is needed, ask.