Existing Repositories

For projects that are already live, the Dev MCP server integrates into maintenance and ongoing support.

File Setup

Create a base .mcp.json file which includes the Dev MCP config in the project directory (as seen in Environment Setup).
Project Context

Create CLAUDE.md with project instructions (this is the only file Claude Code auto-loads). If you prefer to author rules in AGENTS.md, symlink: ln -s AGENTS.md CLAUDE.md
Project Scaffolding
Terminal window
```
claude mcp add-from-file .mcp.json
```
Start Claude Code, activate the appropriate platform agent, then run setup:
```
activate_agent("theme-developer")   # or hydrogen-developer
run setup from Dev MCP
```
Setup will audit the existing project, create INSTRUCTIONS.md, CONVENTIONS.md, and configuration files without modifying existing code. The agent name is saved to project memory for future sessions.
Migrate to Current Standards (if needed)

Run the upgrade command to bring config up to current standards:
```
upgrade
```
This runs health checks and applies any pending migrations non-destructively.

Ongoing Maintenance

Use build for new features — same composition-first rules apply even in legacy codebases
Use refine when updating components to match revised designs
Use maintenance for dependency updates, API version bumps, and configuration drift
Run quality commands (audit, performance, seo, accessibility) periodically or before major releases
Keep CONVENTIONS.md current — it must reflect reality. If you add a component manually, update the file
After any command, numbered next-step suggestions are presented automatically