H3 Use Case Prompt Creator

The other two nodes in this pack solve the "I have an idea, write me an H3 prompt" problem. This one solves the "I have a brief" problem. MiniMax positioned H3 at commercial content creation - ads, brand promos, explainers - and its skills documentation reads like a production handbook: product ads want a variant, in-frame copy, a template and three independent anchors; co-op game intros want player names, a game title and a style lock; music videos want typography direction and beat-reactive shot structure. Knowing which details matter for which deliverable is exactly the kind of expertise a beginner doesn't have. This node encodes it.

Pick one of nine presets and the node shows you only the fields that use case actually cares about:

• Minimalist Product Ad, Brand Promo Video, 3D Animation Short, Co-op Game Intro, Handdrawn Live-Action Fusion, Music Video / Lyric Typography, Paper Collage Explainer, Papercraft Stop-Motion Explainer - or Custom H3 Use Case if none fit.

How it works

Each preset is a guide with its own required fields, production summary and reference rules. The rules are opinionated on purpose - "character refs are identity-only: face silhouette, hairstyle, proportions. Do not inherit photo realism, original lighting or source style," or the product ad's flat "do not use a 4-panel anchor sheet." That's the author's take on what the official skills demand, and it keeps a beginner from feeding the model a reference it will then blindly copy. The node collects only the filled fields for the active use case (stale values from a previous preset can't leak into the prompt), samples up to four frames from a connected reference video, and runs the whole thing through the same H3 guide engine as the rest of the pack - locally on Ollama or against a hosted provider.

The output is where this node stands out. You get three strings:

• h3_prompt - the actual guide-compliant three-field prompt for the sampler.
• production_brief - the planning document: truth sheet, story spine, beats, before any prompt exists. This is the "show your work" output that makes the workflow auditable.
• use_case_analysis - the reasoning behind it.

So it's not just a prompt writer; it's a tiny pre-production department. For a brand promo, for instance, it wants brand_name, official_url, campaign_focus, audience, cta, claims - and its guide explicitly refuses to invent logos, UI or metrics that aren't in your inputs.

The inputs

use_case (required), idea, duration (default 15s), aspect_ratio (16:9, 9:16, 1:1, 4:3, 3:4, 21:9 or "match reference"), language, extra. Then the preset's optional fields light up - product_name/variant/copy/template for ads, story/character_count/world_style for 3D shorts, topic/learning_goal/visual_metaphor for explainers. You can also connect up to six reference images, a reference video and reference audio. There's a Built-in deterministic provider that skips the model entirely and returns a structurally valid (if boilerplate) prompt - handy when you just want to see the format before committing to a model call.

Installing

Same pack as the other two - ComfyUI Manager, search "MiniMax H3 Prompt Creator", restart, or:

cd ComfyUI/custom_nodes
git clone https://github.com/AIJigyasa/ComfyUI-H3-Prompt-Creator

No Python dependencies. The local path needs Ollama with a vision model:

ollama pull qwen3-vl:8b

Gotchas

Two things trip people up. First, the preset fields are dynamic - the widgets shown change with your use_case, which surprises people who expect every field all the time. Second, this node is the strictest of the three about required inputs: pick Co-op Game Intro with empty player1/player2/game_title/style and it will tell you what's missing instead of improvising. Treat that as a feature - H3's commercial formats punish hallucinated brand details. And as with the rest of the pack, keep temperature low (0.25 default) for schema adherence and num_ctx at 8192, or Ollama's default context sizing will drag your generation to a crawl.