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CodeGraphContext Troubleshooting Guide

Use this checklist whenever cgc setup or cgc start doesn’t behave as expected. It keeps the happy path short, but includes the fallback steps when something goes wrong.

1. Prerequisites at a glance

  • Windows + PowerShell commands below assume the py launcher. Adapt to python3 if you’re on macOS/Linux.
  • Python 3.11 (recommended). Run py -3.11 --version to confirm.
  • Neo4j account (only required if you prefer Neo4j AuraDB instead of Docker).

2. Create and activate a virtual environment

From the repository root (CodeGraphContext/):

py -3.11 -m venv venv
.\venv\Scripts\python.exe -m pip install --upgrade pip
  • On Windows, Neo4j driver 6.x can crash with AttributeError: socket.EAI_ADDRFAMILY. If you see that, run: powershell .\venv\Scripts\python.exe -m pip install "neo4j<6"

3. Run the setup wizard (preferred)

Launch the wizard:

.\venv\Scripts\cgc.exe setup

Tip: If you want the wizard to spin up a local Neo4j instance for you, make sure Docker Desktop is installed and running before you launch cgc setup. If Docker isn’t running, the setup wizard will fail when it tries to install Neo4j locally.

What happens next:

  • The wizard checks for Docker. If it’s running, it can auto-provision a local Neo4j instance for you.
  • Alternatively, you can supply credentials for an existing Neo4j AuraDB database.
  • At the end, it generates:
  • mcp.json in your project directory (stores the MCP server command + env vars).
  • ~/.codegraphcontext/.env containing NEO4J_URI, NEO4J_USERNAME, NEO4J_PASSWORD.

Make sure the Docker container (or remote Neo4j) is still running before you start the server.

4. Start the MCP server

Once the wizard completes successfully:

.\venv\Scripts\cgc.exe start

Expected output includes:

Starting CodeGraphContext Server...
...
MCP Server is running. Waiting for requests...

If you instead see:

Configuration Error: Neo4j credentials must be set via environment variables

then either no credentials were saved, or the wizard was skipped—see the manual alternative below.

5. Manual credential setup (fallback)

If you prefer not to use the wizard or need to fix a broken configuration:

  1. Create a mcp.json (or edit the one that exists) in the repository root:

json { "mcpServers": { "CodeGraphContext": { "command": "cgc", "args": ["start"], "env": { "NEO4J_URI": "neo4j+s://YOUR-HOSTNAME:7687", "NEO4J_USERNAME": "neo4j", "NEO4J_PASSWORD": "super-secret-password" } } } }

  1. (Optional) Also create %USERPROFILE%\.codegraphcontext\.env with the same key/value pairs. The CLI loads that file automatically.

  2. Re-run:

powershell .\venv\Scripts\cgc.exe start

6. Common issues & fixes

Symptom Likely Cause Fix
Configuration Error: Neo4j credentials must be set… mcp.json/.env missing or empty Run cgc setup again with Docker running, or create the files manually (section 5).
AttributeError: socket.EAI_ADDRFAMILY Neo4j 6.x bug on Windows Install the 5.x driver: .\venv\Scripts\python.exe -m pip install "neo4j<6" and retry.
Setup wizard fails while pulling Docker image Docker Desktop not running or Docker permissions missing Start Docker Desktop, wait for it to report “Running”, then rerun cgc setup.
Server exits immediately with no log Neo4j instance is offline Check Docker container status or AuraDB dashboard; restart Neo4j and call cgc start again.

7. After the server is running

  • Keep the virtual environment active whenever you run cgc commands.
  • Use pytest from the same env to run tests:

powershell .\venv\Scripts\pytest

  • Front-end website lives under website/ if you need to run npm run dev.

When in doubt, re-run the wizard with Docker active—it regenerates the configuration files without touching your code. Let me know if any section needs clarifying! :)