OpenShowreel

An open-source Model Context Protocol (MCP) server for Adobe After Effects — built so an AI assistant can drive After Effects the way a senior motion designer does: not just dropping keyframes, but applying the mechanics that make a showreel feel premium.

The goal is simple: let an agent take a brief ("animate this UI walkthrough as a 60fps showreel") and produce buttery-smooth, organically-timed motion using the same techniques pros reach for by hand.

Why this exists

Most automated AE tooling produces stiff, robotic motion — linear paths, simultaneous movement, hard fades. The difference between "a computer animated this" and "a designer animated this" comes down to a handful of repeatable mechanics. OpenShowreel encodes those mechanics as MCP tools so they can be composed programmatically.

Core After Effects mechanics the server models

1. 60 FPS + Motion Blur (the baseline for "premium")

Before anything is animated, the composition is set to 60 frames per second and motion blur is enabled. This is the single biggest lever for a "buttery smooth" look — every other technique builds on top of it.

2. Morphing shapes

Basic shape layers become expressive when you uncheck "Constrain Proportions" on the Size property. That lets the X and Y axes scale independently — e.g. a moving button can appear to physically push and stretch a background frame as it travels.

3. Expressions over manual keyframes

Instead of hand-animating physics, the server pastes bounce expressions (small code snippets) into the stopwatch of properties like Scale or Position. Physics for free, tweakable by parameter.

4. Timing offsets — the secret to organic motion

Nested elements should never move with their parent — they lag, just slightly. By appending .valueAtTime(time - 0.1) to an expression, child elements (an arrow inside a button, an icon inside a card) are mathematically forced to animate a fraction of a second behind their container. This kills the stiff, "everything moves at once" feel.

5. Simulated micro-interactions

To make a digital interface feel tactile, the server adds a quick scale-down "button press" keyframe right before a major on-screen movement begins — the same anticipation beat a real tap would produce.

Essential tools the server wraps

Parenting & the Pick Whip

Linking properties together: pick-whip an icon's Scale to its container's Scale, or parent text to a moving shape so it tracks along automatically.

Text Animators + Expression Selectors

Premium text reveals don't just fade in. A Text Animator pushes the starting Position off-screen (e.g. Y → -100) with Opacity at 0%, then an Expression Selector pulls the text into place per-word or per-character — staggered, not all at once.

Null Objects for curved paths

Straight linear motion looks unnatural, so paths are drawn with the pen tool and curved. But curve data can make an object drift when it's meant to be stationary. The fix: snap an invisible Null Object's anchor point to the shape's center, parent the shape to the Null, and animate the Null instead — clean movement, no drift.

The master "camera" finisher

The ultimate polish: create one final master Null Object, attach every otherwise-unlinked element to it, apply an expression, and add a very slight rotation (a small positive tilt followed by a negative one). Moving the whole composition together "stitches it all" into a single cinematic move.

How it works

OpenShowreel is a Node MCP server. Each tool generates a small ExtendScript snippet and runs it inside a running After Effects via macOS AppleScript (osascript → DoScript), wrapped in an undo group, with the result handed back through a temp file. No After Effects panel/extension to install — just the CLI server.

MCP client (Claude, etc.)  ──stdio──►  openshowreel server  ──osascript/DoScript──►  After Effects

Requirements

• macOS with Adobe After Effects installed (auto-detects the newest Adobe After Effects <year> under /Applications; override with AE_APP_NAME).

• After Effects must be running, with Preferences ▸ Scripting & Expressions ▸ "Allow Scripts to Write Files and Access Network" enabled.

• Node.js ≥ 18.

Build & run

npm install
npm run build
npm start          # or: npm run dev   (runs from source via tsx)
npm test           # tool-builder + dry-run tests — no After Effects needed

Set OPENSHOWREEL_DRY_RUN=1 to make every tool report what it would run instead of touching After Effects — handy for testing the wiring.

Register with an MCP client

{
  "mcpServers": {
    "openshowreel": {
      "command": "node",
      "args": ["/absolute/path/to/openshowreel/dist/index.js"]
      // optional: "env": { "AE_APP_NAME": "Adobe After Effects 2025" }
    }
  }
}

Tools

Composition & inspection

Layers

Motion mechanics

Effects, masks, mattes, camera

Scenes, timing, output, escape hatch

See docs/SHOWREEL_PLAYBOOK.md for how to sequence these into a polished reel, and examples/demo-showreel.mjs for a runnable mini-build.

Notes: ExtendScript match-names target current After Effects builds — if a tool errors on another version, ae_eval lets you patch around it (PRs welcome). Under the Advanced 3D renderer the .value getter on shape-layer spatial properties can throw, so OpenShowreel never reads it: pass from explicitly to ae_animate_transform if you need a non-default start value.

Status

🚧 Active development — the bridge and ~40 tools (composition, layers, motion mechanics, effects, masks/mattes, 3D camera, precomps, time remap, device mockups, rendering) are in place and verified live against After Effects 2026. Live behaviour depends on your After Effects version; expect to file/fix the odd match-name. The remaining gap toward fully autonomous reels is mostly direction + assets, not capability — see the playbook.

License

MIT — see LICENSE.