Terraform Skill for Claude Code, Codex, Antigravity, and Gemini CLI: TerraShark

The #1 Terraform skill for Claude Code and Codex, measured by GitHub stars.

Fixes Hallucinations.

LLMs hallucinate a lot when it comes to Terraform. This skill fixes it. It includes best practices for Terraform and OpenTofu - good, bad, and neutral examples so the AI avoids common mistakes. Using TerraShark, the AI keeps proven practices in mind, eliminates hallucinations, and defaults to modular, reusable, security-first design.

Very Token-Efficient.

Most Terraform skills dump huge text-of-walls onto the agent and burn expensive tokens - with no upside. LLMs don't need the entire Terraform docs again. TerraShark was aggressively de-duplicated and optimized for maximum quality per token.

Based on HashiCorp's Official Best Practices.

TerraShark is primarily based on HashiCorp official recommended practices. When guidance conflicts, it prioritizes HashiCorp's recommendations.

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Quick Start • Why TerraShark? • Token Strategy • What's Included • How It Works • Sponsor • Philosophy

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⚡ 2 min Quickstart

Option 1: Clone

macOS / Linux:

git clone https://github.com/LukasNiessen/terrashark.git ~/.claude/skills/terrashark

Windows (Powershell):

git clone https://github.com/LukasNiessen/terrashark.git "$env:USERPROFILE\.claude\skills\terrashark"

Windows (Command Prompt):

git clone https://github.com/LukasNiessen/terrashark.git "%USERPROFILE%\.claude\skills\terrashark"

That's it. Claude Code auto-discovers skills in ~/.claude/skills/ - no restart needed.

Option 2: Marketplace

Claude Code has a built-in plugin system with marketplace support. Instead of cloning manually, you can add TerraShark's marketplace and install directly from the CLI:

/plugin marketplace add LukasNiessen/terrashark
/plugin install terrashark

Or use the interactive plugin manager - run /plugin, switch to the Discover tab, and install from there. The marketplace reads the .claude-plugin/marketplace.json in this repo to register TerraShark as an installable plugin.

Option 3: Codex

Codex has no global skill system - setup is per-project. Clone TerraShark into your repo and reference it from your AGENTS.md:

# Clone into your project root
git clone https://github.com/LukasNiessen/terrashark.git .terrashark

Then add to your AGENTS.md (or create one in the repo root):

## Terraform

When working with Terraform or OpenTofu, follow the workflow in `.terrashark/SKILL.md`.
Load references from `.terrashark/references/` as needed.

Option 4: Antigravity

macOS / Linux:

git clone https://github.com/LukasNiessen/terrashark.git ~/.gemini/antigravity/skills/terrashark

Windows (PowerShell):

git clone https://github.com/LukasNiessen/terrashark.git "$env:USERPROFILE\.gemini\antigravity\skills\terrashark"

Antigravity auto-discovers skills in the skills directory — no restart needed.

Option 5: Gemini CLI

Gemini CLI discovers skills in several standard locations.

Global Installation (All Workspaces):

git clone https://github.com/LukasNiessen/terrashark.git ~/.gemini/skills/terrashark

Local Installation (Current Workspace):

git clone https://github.com/LukasNiessen/terrashark.git .gemini/skills/terrashark

Gemini CLI auto-discovers skills in these directories. Run /skills list in the CLI to verify.

That's it!

Done. Now ask Claude Code / Codex / Antigravity / Gemini CLI any Terraform question. TerraShark responses follow the 7-step failure-mode workflow and include an output contract with assumptions, tradeoffs, and rollback notes.

Invoke explicitly:

/terrashark Create a multi-region S3 module with replication

/terrashark Refactor our EKS stack into separate state files per environment, add moved blocks to avoid recreation, set up a GitHub Actions pipeline with plan on PR and gated apply on merge, and wire in Checkov for compliance scanning

Or just ask naturally - TerraShark activates automatically for any Terraform/OpenTofu task:

Review my main.tf for security issues

Migrate this module from count to for_each

🎬 Demo

https://github.com/user-attachments/assets/2bc4c9ff-9f54-4a49-8bf0-5cfc0f26dec6

📊 Library Comparison

Here's how TerraShark compares to other Terraform and OpenTofu agent skills:

Feature	TerraShark	Anton Babenko terraform-skill	terraform-patterns
Core Architecture	✅ Failure-mode workflow	⚠️ Static reference manual	⚠️ Pattern checklist
SKILL.md Activation Cost	✅ ~600 tokens	⚠️ ~4,400 tokens	⚠️ Single broad reference
Reference Granularity	✅ 19 focused files	⚠️ 6 large files	❌ No focused reference library
Token Burn Per Query	✅ Low (load 1-2 small refs)	⚠️ High for deep references	⚠️ Loads broad guidance
Diagnoses Before Generating	✅ Step 2 requires diagnosis	❌ No	❌ No
Hallucination Prevention	✅ Core design goal