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+# Contributing to Oh My OpenCode
+
+First off, thanks for taking the time to contribute! This document provides guidelines and instructions for contributing to oh-my-opencode.
+
+## Table of Contents
+
+- [Code of Conduct](#code-of-conduct)
+- [Getting Started](#getting-started)
+  - [Prerequisites](#prerequisites)
+  - [Development Setup](#development-setup)
+  - [Testing Your Changes Locally](#testing-your-changes-locally)
+- [Project Structure](#project-structure)
+- [Development Workflow](#development-workflow)
+  - [Build Commands](#build-commands)
+  - [Code Style & Conventions](#code-style--conventions)
+- [Making Changes](#making-changes)
+  - [Adding a New Agent](#adding-a-new-agent)
+  - [Adding a New Hook](#adding-a-new-hook)
+  - [Adding a New Tool](#adding-a-new-tool)
+  - [Adding a New MCP Server](#adding-a-new-mcp-server)
+- [Pull Request Process](#pull-request-process)
+- [Publishing](#publishing)
+- [Getting Help](#getting-help)
+
+## Code of Conduct
+
+Be respectful, inclusive, and constructive. We're all here to make better tools together.
+
+## Getting Started
+
+### Prerequisites
+
+- **Bun** (latest version) - The only supported package manager
+- **TypeScript 5.7.3+** - For type checking and declarations
+- **OpenCode 1.0.150+** - For testing the plugin
+
+### Development Setup
+
+```bash
+# Clone the repository
+git clone https://github.com/code-yeongyu/oh-my-opencode.git
+cd oh-my-opencode
+
+# Install dependencies (bun only - never use npm/yarn)
+bun install
+
+# Build the project
+bun run build
+```
+
+### Testing Your Changes Locally
+
+After making changes, you can test your local build in OpenCode:
+
+1. **Build the project**:
+   ```bash
+   bun run build
+   ```
+
+2. **Update your OpenCode config** (`~/.config/opencode/opencode.json` or `opencode.jsonc`):
+   ```json
+   {
+     "plugin": [
+       "file:///absolute/path/to/oh-my-opencode/dist/index.js"
+     ]
+   }
+   ```
+   
+   For example, if your project is at `/Users/yourname/projects/oh-my-opencode`:
+   ```json
+   {
+     "plugin": [
+       "file:///Users/yourname/projects/oh-my-opencode/dist/index.js"
+     ]
+   }
+   ```
+
+   > **Note**: Remove `"oh-my-opencode"` from the plugin array if it exists, to avoid conflicts with the npm version.
+
+3. **Restart OpenCode** to load the changes.
+
+4. **Verify** the plugin is loaded by checking for OmO agent availability or startup messages.
+
+## Project Structure
+
+```
+oh-my-opencode/
+├── src/
+│   ├── agents/        # AI agents (OmO, oracle, librarian, explore, etc.)
+│   ├── hooks/         # 21 lifecycle hooks
+│   ├── tools/         # LSP (11), AST-Grep, Grep, Glob, etc.
+│   ├── mcp/           # MCP server integrations (context7, websearch_exa, grep_app)
+│   ├── features/      # Claude Code compatibility layers
+│   ├── config/        # Zod schemas and TypeScript types
+│   ├── auth/          # Google Antigravity OAuth
+│   ├── shared/        # Common utilities
+│   └── index.ts       # Main plugin entry (OhMyOpenCodePlugin)
+├── script/            # Build utilities (build-schema.ts, publish.ts)
+├── assets/            # JSON schema
+└── dist/              # Build output (ESM + .d.ts)
+```
+
+## Development Workflow
+
+### Build Commands
+
+```bash
+# Type check only
+bun run typecheck
+
+# Full build (ESM + TypeScript declarations + JSON schema)
+bun run build
+
+# Clean build output and rebuild
+bun run rebuild
+
+# Build schema only (after modifying src/config/schema.ts)
+bun run build:schema
+```
+
+### Code Style & Conventions
+
+| Convention | Rule |
+|------------|------|
+| Package Manager | **Bun only** (`bun run`, `bun build`, `bunx`) |
+| Types | Use `bun-types`, not `@types/node` |
+| Directory Naming | kebab-case (`ast-grep/`, `claude-code-hooks/`) |
+| File Operations | Never use bash commands (mkdir/touch/rm) for file creation in code |
+| Tool Structure | Each tool: `index.ts`, `types.ts`, `constants.ts`, `tools.ts`, `utils.ts` |
+| Hook Pattern | `createXXXHook(input: PluginInput)` function naming |
+| Exports | Barrel pattern (`export * from "./module"` in index.ts) |
+
+**Anti-Patterns (Do Not Do)**:
+- Using npm/yarn instead of bun
+- Using `@types/node` instead of `bun-types`
+- Suppressing TypeScript errors with `as any`, `@ts-ignore`, `@ts-expect-error`
+- Generic AI-generated comment bloat
+- Direct `bun publish` (use GitHub Actions only)
+- Local version modifications in `package.json`
+
+## Making Changes
+
+### Adding a New Agent
+
+1. Create a new `.ts` file in `src/agents/`
+2. Define the agent configuration following existing patterns
+3. Add to `builtinAgents` in `src/agents/index.ts`
+4. Update `src/agents/types.ts` if needed
+5. Run `bun run build:schema` to update the JSON schema
+
+```typescript
+// src/agents/my-agent.ts
+import type { AgentConfig } from "./types";
+
+export const myAgent: AgentConfig = {
+  name: "my-agent",
+  model: "anthropic/claude-sonnet-4-5",
+  description: "Description of what this agent does",
+  prompt: `Your agent's system prompt here`,
+  temperature: 0.1,
+  // ... other config
+};
+```
+
+### Adding a New Hook
+
+1. Create a new directory in `src/hooks/` (kebab-case)
+2. Implement `createXXXHook()` function returning event handlers
+3. Export from `src/hooks/index.ts`
+
+```typescript
+// src/hooks/my-hook/index.ts
+import type { PluginInput } from "@opencode-ai/plugin";
+
+export function createMyHook(input: PluginInput) {
+  return {
+    onSessionStart: async () => {
+      // Hook logic here
+    },
+  };
+}
+```
+
+### Adding a New Tool
+
+1. Create a new directory in `src/tools/` with required files:
+   - `index.ts` - Main exports
+   - `types.ts` - TypeScript interfaces
+   - `constants.ts` - Constants and tool descriptions
+   - `tools.ts` - Tool implementations
+   - `utils.ts` - Helper functions
+2. Add to `builtinTools` in `src/tools/index.ts`
+
+### Adding a New MCP Server
+
+1. Create configuration in `src/mcp/`
+2. Add to `src/mcp/index.ts`
+3. Document in README if it requires external setup
+
+## Pull Request Process
+
+1. **Fork** the repository and create your branch from `master`
+2. **Make changes** following the conventions above
+3. **Build and test** locally:
+   ```bash
+   bun run typecheck  # Ensure no type errors
+   bun run build      # Ensure build succeeds
+   ```
+4. **Test in OpenCode** using the local build method described above
+5. **Commit** with clear, descriptive messages:
+   - Use present tense ("Add feature" not "Added feature")
+   - Reference issues if applicable ("Fix #123")
+6. **Push** to your fork and create a Pull Request
+7. **Describe** your changes clearly in the PR description
+
+### PR Checklist
+
+- [ ] Code follows project conventions
+- [ ] `bun run typecheck` passes
+- [ ] `bun run build` succeeds
+- [ ] Tested locally with OpenCode
+- [ ] Updated documentation if needed (README, AGENTS.md)
+- [ ] No version changes in `package.json`
+
+## Publishing
+
+**Important**: Publishing is handled exclusively through GitHub Actions.
+
+- **Never** run `bun publish` directly (OIDC provenance issues)
+- **Never** modify `package.json` version locally
+- Maintainers use GitHub Actions workflow_dispatch:
+  ```bash
+  gh workflow run publish -f bump=patch  # or minor/major
+  ```
+
+## Getting Help
+
+- **Project Knowledge**: Check `AGENTS.md` for detailed project documentation
+- **Code Patterns**: Review existing implementations in `src/`
+- **Issues**: Open an issue for bugs or feature requests
+- **Discussions**: Start a discussion for questions or ideas
+
+---
+
+Thank you for contributing to Oh My OpenCode! Your efforts help make AI-assisted coding better for everyone.