Gamma Presentation Generator Skill

Generate professional presentations with Gamma AI from your agent. Describe what you want and get a polished deck with direct PDF/PPTX download — no Gamma account needed.

Three Auth Modes

1. BYOK — Bring your own Gamma API key:

export GAMMA_API_KEY=sk-gamma-...

2. Proxy — Route through a managed proxy (no Gamma key needed):

export GAMMA_PROXY_URL=http://your-proxy:8318
export GAMMA_PROXY_KEY=your-proxy-key

3. Managed Config — Shared key or proxy via config file:

// ~/.gamma/config.json — direct key
{"api_key": "sk-gamma-..."}

// ~/.gamma/config.json — proxy mode
{"proxy_url": "http://your-proxy:8318", "proxy_key": "your-proxy-key"}

Usage

# Simple topic → PDF
bun run generate.ts --topic "Q2 Product Roadmap" --format pdf --output ./roadmap.pdf

# Full content with exact slide control (30+ slides)
bun run generate.ts --content-file ./outline.md \
  --text-mode preserve --card-split inputTextBreaks \
  --format pptx --output ./presentation.pptx

CLI Options

Flag	Values	Default	Description
--topic	string	—	Short topic description
--content	string	—	Full content inline
--content-file	path	—	Read content from file
--format	pdf, pptx	pdf	Export format
--pages	number	—	Target slide count
--output	path	/tmp/gamma-output.{ext}	Output file path
--text-mode	generate, condense, preserve	generate	How Gamma treats your text
--card-split	auto, inputTextBreaks	auto	How to split into slides

Text Mode Guide

• generate — Gamma rewrites and expands (best for topics/outlines)
• condense — Gamma shortens to fit slides
• preserve — Gamma keeps your text as-is (best for pre-written content)

For 20+ slides with exact content: --text-mode preserve --card-split inputTextBreaks

Proxy Server (gamma-proxy.ts)

Run a Bun sidecar that holds your Gamma API key and serves whitelisted users:

GAMMA_PROXY_AUTH_KEY=your-secret-key bun run gamma-proxy.ts
# Runs on port 8318

Whitelist additional keys in ~/.gamma/whitelist.json:

["key-for-friend-1", "key-for-teammate-2"]

Install

Claude Code

ln -s /path/to/gamma-skill ~/.claude/skills/gamma

OpenClaw / PCClaw

cp SKILL.md ~/.openclaw/skills/gamma/SKILL.md

How It Works

1. Skill receives topic or content from the user
2. Calls Gamma API with exportAs parameter for direct download
3. Polls until generation completes (~30-120s)
4. Downloads PDF/PPTX directly via exportUrl
5. Returns the file path to the user

Cost

~15-136 credits per deck depending on size. Skill owner covers generation costs.

Requirements

• Bun runtime
• Gamma API key (get one at gamma.app) OR access to a gamma-proxy instance

License

MIT