diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index e03f446ab..e9922cf19 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -16,9 +16,14 @@ This project uses the [PolyForm Noncommercial License 1.0.0](https://polyformpro
 **Prerequisites:** Node.js — `gitnexus/` requires `>=22.0.0` and `gitnexus-web/` requires `^20.19.0 || >=22.12.0` (enforced via the `engines` field in each package). Use `nvm install` to match the local version.
 
 1. Clone the repository.
-2. **CLI / MCP package:** `cd gitnexus && npm install && npm run build`
-3. **Web UI (if needed):** `cd gitnexus-web && npm install`
-4. Run tests as described in [TESTING.md](TESTING.md).
+2. **Shared package:** `cd gitnexus-shared && npm install && npm run build`
+3. **CLI / MCP package:** `cd ../gitnexus && npm install && npm run build`
+4. **Web UI (if needed):** `cd ../gitnexus-web && npm install`
+5. Run tests as described in [TESTING.md](TESTING.md).
+
+The CLI build imports `gitnexus-shared`, so a fresh clone must install and build
+the shared package before running `npm install` in `gitnexus/`. This is the same
+order used by the repository's `setup-gitnexus` CI action.
 
 ### Containerized development (optional)