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Documentation Index

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Add dynamic, stylized captions that match your video’s tone, improve retention, and boost accessibility. Ideal for social platforms where sound-off viewing is common (TikTok, Reels, Shorts, LinkedIn).

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How It Works

The Captions tile listens to your video audio, transcribes speech, and overlays timed captions. You control how they look — from fonts and stroke to placement and coloring. Captions are auto-timed to speech and update in real-time based on your styling choices. Clean captions

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Input and Settings

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Caption Style

Controls how captions are visually rendered. API caption_style values:
  • colored → Highlights key words with your highlight_color
  • scaling → Emphasis via animated word scaling
  • karaoke → Progressive karaoke-style emphasis
stroke_color and stroke_width are controlled separately from caption_style. Great for:
  • Retention editing
  • Educational clips
  • Talking-head explanatory content

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Colors

You can customize three visual layers: Base Color
Default text color (e.g., #FFFFFF for white) Highlight Color
Used to emphasize specific words — increases engagement & readability Stroke Color
Outline around text for contrast on busy footage

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Font Options

Set the typography style to match your brand. Controls include:
  • Font Family (e.g., Montserrat)
  • Font Weight (e.g., 400 / 700)
  • Font Size (slider)
Use cases:
  • Bold fonts for TikTok/Shorts
  • Light/fonts for cinematic edits

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Vertical Position

Adjust how high/low captions sit in the frame (via percentage slider). Examples:
  • 90% → Just above bottom edge (common for shorts)
  • 50% → Centered (cinematic)
  • 20% → Top aligned (when lower third is busy)

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Words per Caption

Controls pacing and readability. Two sliders:
  • Minimum words
  • Maximum words
Examples:
  • Min 1 / Max 3 → Fast TikTok pacing
  • Min 3 / Max 7 → YouTube educational pacing

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API Info

  • Node ID: cdccb204-168e-4aec-aa72-480b11e74324

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Node params

ParamTypeRequiredDefaultNotes
caption_style"colored" | "scaling" | "karaoke"No"colored"Visual style preset.
base_colorstring (hex)No"#F8FAFC"Primary text color.
highlight_colorstring (hex)No"#A78BCA"Highlight/accent color.
stroke_colorstring (hex)No"#0B0B0B"Stroke/outline color.
stroke_widthnumberNo14Stroke/outline width (0-20).
caption_fontstringNo"Montserrat"Font family.
caption_font_weightstringNo"700"Font weight as string token.
caption_font_sizenumberNo108Font size in pixels (20-120).
caption_vertical_positionnumber (percent)No88Vertical caption placement (10-90).
caption_min_wordsnumberNo2Minimum words grouped per caption chunk (1-8).
caption_max_wordsnumberNo4Maximum words grouped per caption chunk (1-8).

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Parameter groups

  • Render style: caption_style, base_color, highlight_color, stroke_color, stroke_width
  • Typography: caption_font, caption_font_weight, caption_font_size
  • Layout & pacing: caption_vertical_position, caption_min_words, caption_max_words

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Scenario requirements

  • Keep caption_min_words <= caption_max_words.
  • Use valid hex color strings for color fields.
  • caption_font_weight must be sent as a string (for example "700"), not a number.

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Runtime notes

  • For deterministic output, set style, typography, and pacing fields explicitly.
  • For API overrides, pass these fields via update_params[agent_node_id].

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Example

{
  "caption_style": "colored",
  "base_color": "#FFFFFF",
  "highlight_color": "#EC81EE",
  "caption_font": "Montserrat",
  "caption_font_weight": "700",
  "caption_font_size": 108,
  "caption_vertical_position": 88,
  "caption_min_words": 2,
  "caption_max_words": 4
}