/video-explainer

name: video-explainer
description: Turn a research brief, finished script, or generated MP4 into a reviewed and verified vertical explainer video. Use when an agent should choose the simplest current production strategy, preserve strict final-artifact quality gates, run the deterministic Remotion fallback, diagnose the local toolchain, or verify an existing MP4 before any manual publication step.

Video Explainer

Version note: v0.3.0-rc.1 / 2026-09-27 / Make production strategy adaptive while keeping the deterministic Remotion recipe as a strict fallback. Final-artifact acceptance is strategy-independent and bound to the exact MP4 bytes. Keep upload, account access, credentials, private voice assets, hosted rendering, and publication out of scope.

Produce a local video and evidence packet. Never upload or publish from this skill.

Core contract

This Skill separates **what must be true of the final artifact** from **how the artifact is produced**.

Before forcing an existing recipe, run a capability challenge:

1. Can the current model or available capability produce the final MP4 directly at the required quality? 2. Which requirements are real product, safety, brand, or evidence invariants? 3. Which existing steps only compensate for older model limitations? 4. Can intermediate stages be skipped without weakening final acceptance? 5. What is the simplest strategy likely to pass the final gates? 6. If that strategy fails, fall back to the deterministic repository-owned recipe.

Choose one execution strategy:

• `direct_artifact` — a current model/capability produces the final MP4 directly. Do not require `motion-storyboard.json`, `script.json`, TTS, alignment, or Remotion merely to satisfy a historical recipe.
• `agent_orchestrated` — an agent may choose and combine tools as implementation details. Intermediate artifacts are optional unless they are needed to satisfy the brief or evidence requirements.
• `legacy_remotion` — use the repository-owned deterministic path when direct generation cannot preserve facts, branding, layout control, narration identity, or other required qualities.

All three strategies converge on objective MP4 verification plus an independent final-artifact review. Production freedom never bypasses final acceptance.

Install

The deterministic fallback orchestrates a local clone of `claude-video-kit`; it does not bundle the renderer. From the repository root, install the runtime and register the Skill with:

npm ci --prefix remotion
npx skills add runesleo/claude-video-kit --skill video-explainer

For repository development, run commands from the repository root.

Workflow

1. Read the brief and run the capability challenge above. Select `direct_artifact`, `agent_orchestrated`, or `legacy_remotion`. Prefer the simplest strategy that can plausibly pass the same final acceptance contract.

2. If using `direct_artifact` or `agent_orchestrated`, produce the final 9:16 MP4 without manufacturing legacy intermediate files just to satisfy the old recipe. Then skip to Step 6.

3. If using `legacy_remotion`, run the read-only doctor before changing a project:

   node scripts/video-explainer.mjs doctor --output <output-directory>

Read [setup-and-doctor.md](references/setup-and-doctor.md) when doctor blocks or the environment is new.

4. For `legacy_remotion`, turn the brief into `motion-storyboard.json` **before** treating the script as ready. For every scene, define its information purpose, visual metaphor, motion grammar, why motion communicates better than a static card, duration hint, and explicit 3D decision.

Read [motion-storyboard.md](references/motion-storyboard.md), then validate:

   python3 scripts/check_storyboard.py <project>

Production planning in this deterministic path must not default to title + card + bullets. Generic entrance/exit effects (`fade`, `slide`, `zoom`, etc.) do not count as an information model by themselves. 3D is an exception that must earn its render/debug cost with a concrete comprehension benefit.

5. For `legacy_remotion`, convert the approved information plan into `script.json`, require the independent pre-render review, and render only from a current pass receipt:

   node scripts/video-explainer.mjs review <project> --input <project>/review-input.json
   node scripts/video-explainer.mjs render <project>

Read [brief-to-script.md](references/brief-to-script.md) and [review-gate.md](references/review-gate.md). The pre-render gate checks facts, structure, duration, visual feasibility, hierarchy, simplicity, clarity, legibility, craft, privacy, and copyright. Any script edit makes that receipt stale.

On macOS, use `--demo-quality` only for a credential-free first success. It forces the built-in demo voice and script-timed captions; that explicit demo path may omit a storyboard and is never publication-quality. Read [render-and-verify.md](references/render-and-verify.md) before running a custom project.

6. For **every strategy**, verify the exact final MP4 objectively:

   node scripts/verify-shorts.mjs <video.mp4>

For the deterministic Remotion path, prefer bound render metadata when available:

   node scripts/verify-shorts.mjs <project>/out/full.mp4 \
     --metadata <project>/metadata.json

The objective verifier checks canvas, duration, and scene rhythm. It does **not** prove factual correctness, visual polish, privacy, copyright, narration consistency, or end-card correctness.

7. Require an independent final-artifact review bound to the exact MP4 SHA-256:

   node scripts/video-explainer.mjs review-render <video.mp4> \
     --input <render-review-input.json>

The final-artifact review is strategy-independent. It requires:

• facts
• structure
• duration
• hierarchy
• simplicity
• clarity
• legibility
• craft
• privacy
• copyright
• au