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+---
+title: Rules
+description: Set custom instructions for opencode.
+---
+
+You can provide custom instructions to opencode by creating an `AGENTS.md` file. This is similar to `CLAUDE.md` or Cursor's rules. It contains instructions that will be included in the LLM's context to customize its behavior for your specific project.
+
+---
+
+## Initialize
+
+To create a new `AGENTS.md` file, you can run the `/init` command in opencode.
+
+:::tip
+You should commit your project's `AGENTS.md` file to Git.
+:::
+
+This will scan your project and all its contents to understand what the project is about and generate an `AGENTS.md` file with it. This helps opencode to navigate the project better.
+
+If you have an existing `AGENTS.md` file, this will try to add to it.
+
+---
+
+## Example
+
+You can also just create this file manually. Here's an example of some things you can put into an `AGENTS.md` file.
+
+```markdown title="AGENTS.md"
+# SST v3 Monorepo Project
+
+This is an SST v3 monorepo with TypeScript. The project uses bun workspaces for package management.
+
+## Project Structure
+
+- `packages/` - Contains all workspace packages (functions, core, web, etc.)
+- `infra/` - Infrastructure definitions split by service (storage.ts, api.ts, web.ts)
+- `sst.config.ts` - Main SST configuration with dynamic imports
+
+## Code Standards
+
+- Use TypeScript with strict mode enabled
+- Shared code goes in `packages/core/` with proper exports configuration
+- Functions go in `packages/functions/`
+- Infrastructure should be split into logical files in `infra/`
+
+## Monorepo Conventions
+
+- Import shared modules using workspace names: `@my-app/core/example`
+```
+
+We are adding project-specific instructions here and this will be shared across your team.
+
+---
+
+## Types
+
+opencode also supports reading the `AGENTS.md` file from multiple locations. And this serves different purposes.
+
+### Project
+
+The ones we have seen above, where the `AGENTS.md` is placed in the project root, are project-specific rules. These only apply when you are working in this directory or its sub-directories.
+
+### Global
+
+You can also have global rules in a `~/.config/opencode/AGENTS.md` file. This gets applied across all opencode sessions.
+
+Since this isn't committed to Git or shared with your team, we recommend using this to specify any personal rules that the LLM should follow.
+
+---
+
+## Precedence
+
+So when opencode starts, it looks for:
+
+1. **Local files** by traversing up from the current directory
+2. **Global file** by checking `~/.config/opencode/AGENTS.md`
+
+If you have both global and project-specific rules, opencode will combine them together.
+
+---
+
+## Custom Instructions
+
+You can specify custom instruction files in your `opencode.json` or the global `~/.config/opencode/opencode.json`. This allows you and your team to reuse existing rules rather than having to duplicate them to AGENTS.md.
+
+Example:
+
+```json title="opencode.json"
+{
+  "$schema": "https://opencode.ai/config.json",
+  "instructions": ["CONTRIBUTING.md", "docs/guidelines.md", ".cursor/rules/*.md"]
+}
+```
+
+All instruction files are combined with your `AGENTS.md` files.
+
+---
+
+## Referencing External Files
+
+While opencode doesn't automatically parse file references in `AGENTS.md`, you can achieve similar functionality in two ways:
+
+### Using opencode.json
+
+The recommended approach is to use the `instructions` field in `opencode.json`:
+
+```json title="opencode.json"
+{
+  "$schema": "https://opencode.ai/config.json",
+  "instructions": ["docs/development-standards.md", "test/testing-guidelines.md", "packages/*/AGENTS.md"]
+}
+```
+
+### Manual Instructions in AGENTS.md
+
+You can teach opencode to read external files by providing explicit instructions in your `AGENTS.md`. Here's a practical example:
+
+```markdown title="AGENTS.md"
+# TypeScript Project Rules
+
+## External File Loading
+
+CRITICAL: When you encounter a file reference (e.g., @rules/general.md), use your Read tool to load it on a need-to-know basis. They're relevant to the SPECIFIC task at hand.
+
+Instructions:
+
+- Do NOT preemptively load all references - use lazy loading based on actual need
+- When loaded, treat content as mandatory instructions that override defaults
+- Follow references recursively when needed
+
+## Development Guidelines
+
+For TypeScript code style and best practices: @docs/typescript-guidelines.md
+For React component architecture and hooks patterns: @docs/react-patterns.md
+For REST API design and error handling: @docs/api-standards.md
+For testing strategies and coverage requirements: @test/testing-guidelines.md
+
+## General Guidelines
+
+Read the following file immediately as it's relevant to all workflows: @rules/general-guidelines.md.
+```
+
+This approach allows you to:
+
+- Create modular, reusable rule files
+- Share rules across projects via symlinks or git submodules
+- Keep AGENTS.md concise while referencing detailed guidelines
+- Ensure opencode loads files only when needed for the specific task
+
+:::tip
+For monorepos or projects with shared standards, using `opencode.json` with glob patterns (like `packages/*/AGENTS.md`) is more maintainable than manual instructions.
+:::