Scenario Text Overlay

Overview

Generation models drift on type, so text that must be exact is rendered deterministically here and composited over the media. One JSON payload describes one overlay, in one of two kinds: a text layer (plain styled text in a box) or a rich layer (HTML/CSS typography: gradients, strokes, shadows, card layouts). Both substitute Mustache {{variables}} strictly (a missing variable fails the render) on a transparent canvas.

scripts/overlay.py renders the payload to a PNG with an installed Chromium-family browser (both kinds, discovered automatically) or a Pillow fallback (text layers only), embeds the payload JSON into the PNG, and prints the path. Its modules: scripts/templating.py (strict Mustache), scripts/html_render.py (browser engine), scripts/pillow_render.py (fallback). The field-by-field contract and example payloads live in references/payloads.md. The script needs pip install chevron pillow.

Connection and the core MCP loop: see the scenario skill. The overlay meets its content on the platform, never locally: model_run on the compose tool models, model_scenario-compose-image for stills and model_scenario-compose-video for video (fixed ids: each is Scenario's single deterministic compositor for its medium, so discovery would only re-derive them), whose layer contract lives in scenario-video-assembly. If a sibling skill named here is missing from your available skills, ask the user to install it (npx skills add scenario-labs/skills --skill <name>); unattended, proceed from tool schemas and flag the gap.

Quick reference