How to Give Claude Code Context Across Repositories

Before you start

• Claude Code installed and signed in (claude --version should work).
• The repositories you care about, ideally cloned side by side, for example ~/code/web, ~/code/api and ~/code/shared.

Step 1: List which repositories a change touches

Before you open Claude, write down the path of the change: the code that starts the behaviour (for example web), every service it calls (api), and every shared package involved (shared). If you can't answer this, skip to step 4; that's exactly the problem an index solves.

Step 2: Start Claude Code with those repositories

From the main repository, add the others as extra working directories:

cd ~/code/web
claude --add-dir ../api --add-dir ../shared

Already in a session? Use /add-dir ../api.

Then confirm Claude can see them:

"List the top-level folders you can access and summarise what each repository does."

Step 3: Write a cross-repository CLAUDE.md

Create a CLAUDE.md in your main repository describing how the pieces connect:

## System map
- web: Next.js frontend. Calls api over REST (/v1/*).
- api: Node service. Owns the orders and payments tables.
- shared: types and validation used by both web and api.

## Rules
- Changing an API response? Check web/src/lib/api.ts for consumers.
- Shared types change? Update both web and api in the same task.

Claude reads this at the start of each session, so it begins with a map instead of rediscovering the system every time.

Step 4: Add organisation-wide context with CodeZero

Steps 1–3 depend on you knowing the system and keeping the notes up to date. For larger organisations, use CodeZero, a VS Code extension that sits alongside Claude Code.

1. Install CodeZero from the VS Code Marketplace (requires VS Code 1.90.0 or newer).
2. Sign in with Frigga and select your organisation.
3. Connect GitHub, GitLab or Bitbucket and choose the repositories to index. Indexing runs in the background.
4. Open the Files view. You'll see every indexed repository, including ones you haven't cloned, and you can open their files from the index.
5. Ask in CodeZero's chat, for example: "Which services consume the orders API, and where?" The answer can draw on evidence from any indexed repository.
6. Plan the change. A plan can name several repositories; CodeZero keeps them in scope for Claude and shows the dependencies in Tasks.
7. Clone only what you edit. If the plan needs to write to a repository you haven't cloned, Tasks offers Clone, and you choose where.

Check it worked

Ask a question that can only be answered with another repository's code:

"If I rename the status field in the orders response, what breaks in other repositories?"

A good answer names specific files in other repositories. A vague answer means Claude still can't see them.