google-flow-scripting-skill

Google Flow and Veo Prompting Skill for Consistent AI Video

An open-source Google Flow, Veo 3.1, and Gemini Omni Flash production workflow for character consistency, multi-scene continuity, visual storyboards, cinematic prompts, and pre-generation validation.

What this project solves

Independent AI video generations have no guaranteed implicit memory. Faces drift, clothing changes, sets rearrange, props break, text appears unexpectedly, and clips fail to join cleanly.

This Skill turns continuity into an explicit production system:

• canonical @ReferenceHandles for characters and locations
• cast, environment, prop, and state inventories
• model-specific reference allocation
• visual storyboard contact sheets before video generation
• self-contained segment prompts
• first-frame, last-frame, extension, edit, and cut planning when supported
• mechanical prompt validation
• human continuity auditing

It is an unofficial workflow and is not affiliated with Google.

Version 1.6.0 highlights

• Safe, checksum-verified update system for downloaded and installed releases
• Cross-platform Python installer with Bash and PowerShell launchers
• Permanent release notes for every version
• Automated version consistency, package manifest, and release archive checks
• Tag-driven GitHub Release publishing
• Executable storyboard prompt generator
• Strict four-panel 2x2 contract for ten-second scenes with four authored states
• Canonical @PascalCase reference enforcement
• Package-wide em-dash prohibition
• Surface, model, mode, and duration validation

See CHANGELOG.md and release-history/ for the complete history.

Quick start

Clone the source repository

git clone https://github.com/agbelemi/google-flow-scripting-skill.git
cd google-flow-scripting-skill
python scripts/verify_package.py .
python tests/run_tests.py
python scripts/install.py --tool cursor

Supported installer targets:

claude-code
cursor
windsurf
generic

Bash and PowerShell launchers are also included:

./scripts/install.sh --tool cursor
powershell -ExecutionPolicy Bypass -File scripts/install.ps1 --tool cursor

Use without installation

Open SKILL.md in an AI coding assistant, or paste reference/PLAYBOOK.md and the specialist file you need into the conversation.

Start every project with the production profile

Do not write timed scenes until these are known:

SURFACE: Google Flow or Gemini API
MODEL: Veo 3.1 variant, Gemini Omni Flash, or another named model
MODE: Text to Video, First Frame, First and Last Frame, References to Video, Video Edit, or Extend
SEGMENT LENGTH: supported whole seconds
ASPECT RATIO: usually 16:9 or 9:16

Current reviewed examples:

• Flow Veo 3.1 Lite and Fast: 4, 6, or 8 seconds for ordinary generation
• Flow Veo 3.1 Quality: 8 seconds in current credit documentation
• Flow Gemini Omni Flash: 4, 6, 8, or 10 seconds
• Gemini API Veo 3.1: 4, 6, or 8 seconds with feature-specific restrictions
• Gemini API Omni Flash: 3 through 10 seconds at 720p and 24 FPS

Capabilities change. Read reference/FLOW-FEATURES.md and confirm the active interface.

Canonical reference rule

Every generated character or location reference begins with @ and uses one alphanumeric PascalCase name:

@Kwame
@CafeLadies
@SidewalkCafe

Incorrect:

Kwame
@Cafe Ladies
Sidewalk Cafe
@Sidewalk-Cafe

Use the same handle in asset records, operator notes, storyboard prompts, video prompts, attachment lists, and audits.

Visual storyboard rule

The storyboard-generation contract is hard-coded:

"A storyboard-generation prompt must command image generation in its first sentence, declare the exact output count and layout, prohibit planning responses, and enumerate forbidden invented actions."

Every copy-paste storyboard prompt begins exactly with:

GENERATE THE STORYBOARD IMAGE NOW.

Default contact sheets:

Segment	Default panels	Layout
4 seconds	2	2x1
6 seconds	3	3x1
8 seconds	3	3x1
10 seconds	4	2x2

Use a 3x3 grid only when nine distinct frames were explicitly authored. Do not let the generator invent filler actions.

Generate a storyboard package from JSON:

python scripts/generate_storyboard_prompt.py examples/storyboard-spec.json \
  --output storyboard-package.md

The output separates:

1. internal operator notes
2. the copy-paste image-generation prompt
3. the human approval checklist

Validate a script

Flow and Omni reference generation:

python scripts/validate.py storyboard-package.md \
  --segment-length 10 \
  --surface flow \
  --model omni-flash \
  --mode references-to-video \
  --beat-mode off \
  --no-require-audio

Flow and Veo text to video:

python scripts/validate.py video-script.md \
  --segment-length 8 \
  --surface flow \
  --model veo-3.1-fast \
  --mode text-to-video \
  --beat-mode exact

Timing modes:

exact     one line for every second
coverage  continuous intervals with no gaps or overlaps
loose     ordered timing cues without full coverage
 off      no timing validation

The validator checks:

• vague backward references
• text-bleed tokens
• prohibited em dashes
• prompt text policy
• canonical @ReferenceHandles
• storyboard output contract and panel order
• beat order, gaps, overlaps, duplicates, and duration
• surface, model, mode, and duration compatibility
• unsupported aspect ratios
• audio direction when required
• advisory Veo API prompt length

It does not replace visual review or continuity judgement.

Specialist roster

Core craft

File	Responsibility
core/flow-orchestrator.md	Intake, capability profile, routing, and sequencing
core/flow-story-architect.md	Runtime arithmetic, segment map, state ledger, and story structure
core/flow-asset-manager.md	Canonical handles, references, plates, environments, and allocation
core/flow-storyboard-director.md	Visual contact-sheet prompts and storyboard approval gate
core/flow-continuity-auditor.md	Final adversarial continuity audit

Format specialists

• formats/flow-3d-animation.md
• formats/flow-2d-animation.md
• formats/flow-live-action.md
• formats/flow-documentary.md
• formats/flow-ads.md
• formats/flow-music-video.md

Updating an installed copy

Downloaded ZIP files and installed AI Skills do not update automatically.

Check for a release:

python scripts/check_update.py

Apply a verified update:

python scripts/update.py

The updater:

• requires a versioned GitHub Release asset
• verifies SHA256SUMS
• verifies the internal MANIFEST.json
• runs the full package tests
• detects local modifications
• creates a timestamped backup
• refuses silent replacement
• refuses to replace a Git working tree by default

Git clones should update with:

git pull --ff-only origin main
python tests/run_tests.py
python scripts/install.py --tool cursor --force

Restart the AI host or begin a new session after updating. See reference/UPDATE-GUIDE.md.

Building and publishing releases

Prepare a new version:

python scripts/start_release.py 1.7.0 --date 2026-08-01

Verify and build:

python scripts/verify_package.py .
python tests/run_tests.py
python scripts/build_release.py --output dist

Pushing a matching tag such as v1.7.0 triggers .github/workflows/release.yml, which runs tests, builds ZIP and tar.gz assets, writes checksums, creates provenance attestations, and publishes a GitHub Release using the permanent record in release-history/v1.7.0.md.

See reference/RELEASE-PROCESS.md.

Release history policy

Every published version must have:

• a VERSION value
• a matching SKILL.md version
• a root changelog section
• a permanent release-history/vVERSION.md file
• an entry in release-history/index.json
• a matching Git tag
• versioned release asset filenames

Old release records are never deleted. Later corrections are appended as explicit correction notes.

Security and support

• SECURITY.md
• SUPPORT.md
• CODE_OF_CONDUCT.md
• CONTRIBUTING.md

License

MIT. See LICENSE.