# Ae Config Builder > Create and validate JSON automation configs for the After Effects automation pipeline - Skill: `jhd3197/ae-config-builder` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add jhd3197/ae-config-builder` - Raw SKILL.md: https://api.skillmd.com/api/skills/jhd3197/ae-config-builder/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: DevOps & Infra - Author: jhd3197 (https://skillmd.com/u/jhd3197) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/jhd3197/ae-config-builder --- # AE Config Builder This skill covers creating and validating JSON configuration files that drive the After Effects automation pipeline. Configs are loaded by `botMixin.startBot()` and control the entire workflow from project setup through rendering. ## Top-Level Structure ```json { "project": { ... }, "timeline": [ ... ], "templates": { ... } } ``` - **`project`** (required) -- Output settings, composition parameters, and resource definitions - **`timeline`** (required) -- Array of scene objects, each with custom actions - **`templates`** (optional) -- Reusable action templates with variable substitution ## Project Section All fields and their types: | Field | Type | Required | Description | |-------|------|----------|-------------| | `project_file` | string | Yes | Path to `.aep` file (relative to config file or absolute) | | `comp_name` | string | Yes | Main composition name in the AE project | | `comp_fps` | number | Yes | Frame rate (e.g., `29.97`, `30`, `60`) | | `comp_width` | number | Yes | Composition width in pixels | | `comp_height` | number | Yes | Composition height in pixels | | `comp_start_time` | string | No | Start time as `"HH:MM:SS"` | | `comp_end_time` | number or string | No | End time -- seconds (e.g., `15`) or `"HH:MM:SS"` format | | `auto_time` | boolean | No | Auto-calculate composition duration from timeline | | `output_file` | string | Yes | Output filename (e.g., `"output.mp4"`) | | `output_dir` | string | Yes | Output directory path (relative to config or absolute) | | `renderComp` | boolean | No | Whether to render after building (default: `true`) | | `debug` | boolean | No | Skip AE launch and UI interaction for testing | | `resources` | array | No | External assets to import (see below) | ### comp_end_time Dual Format ```json "comp_end_time": 15 "comp_end_time": "00:00:15" ``` Both are valid. The number format specifies seconds directly. The string format is parsed by `timeToFrames()`. ### Debug Mode Setting `"debug": true` prevents AE from launching and skips all UI interaction. Useful for: - Validating config structure - Testing config loading - CI/CD pipelines - Dry-run validation ### Path Resolution Paths in `project_file` and `output_dir` can be relative. They are resolved relative to the **config file's directory** by `startBot()`: ```json { "project": { "project_file": ".\\my_template.aep", "output_dir": ".\\output" } } ``` Use `.\` or `./` prefix for relative paths. Forward slashes work on all platforms. ### Resources Array Resources are external assets (images, audio, video) imported into the AE project: ```json "resources": [ { "type": "image", "name": "background", "path": "C:/assets/bg.png" }, { "type": "audio", "name": "bgm", "path": "C:/assets/music.mp3", "duration": 30 }, { "type": "video", "name": "footage", "path": "C:/assets/clip.mp4" } ] ``` - `type` -- `"image"`, `"audio"`, or `"video"` - `name` -- Identifier used to reference this resource in timeline actions - `path` -- Absolute path to the asset file - `duration` -- Optional; for MP3 audio the duration is auto-detected if omitted ## Timeline Section An array of scene objects processed in order: ```json "timeline": [ { "name": "intro_scene", "duration": 5, "startTime": 0, "template_comp": "IntroTemplate", "reverse": false, "custom_actions": [ ... ] }, { "name": "content_scene", "duration": 10, "startTime": 5, "template_comp": "ContentTemplate", "reverse": false, "custom_actions": [ ... ] } ] ``` ### Scene Object Fields | Field | Type | Required | Description | |-------|------|----------|-------------| | `name` | string | Yes | Scene identifier (used for folder naming via `slug()`) | | `duration` | number | Yes | Scene duration in seconds | | `startTime` | number | Yes | Scene start time in seconds within the main comp | | `template_comp` | string | Yes | Name of the AE template composition to duplicate | | `reverse` | boolean | No | Reverse the scene playback | | `custom_actions` | array | Yes | Array of action objects to apply to this scene | ## Custom Actions Each action object must have a `change_type` field that routes to the corresponding handler. See [references/config-schema.md](references/config-schema.md) for the complete catalogue of all 8 change types with full field definitions. ### Quick Reference | `change_type` | Purpose | |----------------|---------| | `update_layer_property` | Set a layer property (text, color, position, etc.) | | `update_layer_property_at_frame` | Set a keyframe value at a specific frame | | `add_resource` | Add an imported resource to the timeline | | `edit_resource` | Modify an existing resource layer's timing | | `swap_items_by_index` | Replace a layer's source item | | `add_marker` | Add a composition marker | | `add_comp` | Add a nested composition to the timeline | | `template` | Apply a reusable template with variable substitution | ## Property Dot-Notation Layer properties use dot-separated paths that `propertyParser()` traverses: ``` "Text.Source Text" -- Text layer content "Text.Path Options.Path" -- Text path "Transform.Position" -- Layer position [x,y] "Transform.Scale" -- Layer scale [x,y] "Transform.Opacity" -- Layer opacity (0-100) "Transform.Rotation" -- Layer rotation in degrees "Effects.Color_01.Color" -- Effect parameter (effect name.property) "Effects.Slider_01.Slider" -- Effect slider value ``` The first segment selects the property group, subsequent segments drill into sub-properties. ## Value Formats ### Strings ```json "value": "Hello World" ``` ### Hex Colors ```json "value": "#FF0000", "property_type": "color" ``` When `property_type` is `"color"`, the hex value is auto-converted to AE's normalized RGBA format (`"1.0,0.0,0.0,1"`) by `hexToRGBA()` before being sent to JSX. ### Arrays (as strings) ```json "value": "[960,540]" ``` Arrays are passed as string representations. The `valueParser()` function in `framework.js` detects the `[` prefix and parses them into actual arrays. ### Numbers ```json "value": "100" ``` Numeric values are also passed as strings and parsed by `valueParser()`. ## Templates Section Define reusable action groups with `{key}` variable substitution: ```json { "templates": { "update_title": { "custom_actions": [ { "change_type": "update_layer_property", "comp_name": "{comp}", "layer_name": "Title", "property_name": "Text.Source Text", "property_type": "string", "value": "{title_text}" }, { "change_type": "update_layer_property", "comp_name": "{comp}", "layer_name": "Title", "property_name": "Effects.Color_01.Color", "property_type": "color", "value": "{title_color}" } ] } }, "timeline": [ { "name": "scene_1", "template_comp": "SceneTemplate", "duration": 5, "startTime": 0, "custom_actions": [ { "change_type": "template", "template_name": "update_title", "template_values": { "comp": "scene_1_SceneTemplate", "title_text": "Welcome", "title_color": "#FFFFFF" } } ] } ] } ``` The `template` change_type looks up `data["templates"][template_name]`, replaces all `{key}` placeholders with `template_values`, then recursively processes each resulting action through `parseCustomActions()`.