fo-semantic-mcp Setup for Codex

About Codex CLI

OpenAI Codex CLI is a lightweight coding agent that runs in your terminal. It supports the Model Context Protocol (MCP), allowing you to connect fo-semantic-mcp for AI-assisted D365 F&O development.

Configuration Steps

1. Locate Your Codex Config File

   Codex stores its configuration in config.toml:

   Windows:

   C:\Users\<username>\.codex\config.toml

   macOS / Linux:

   ~/.codex/config.toml
2. Get Your API Key

   Sign in to xplusplus.ai and get your API key from the dashboard.

   Get API Key
3. Add MCP Server Configuration

   Open your config.toml file and add the fo-semantic-mcp server configuration:

   # Your existing Codex settings model = "gpt-4.1" model_reasoning_effort = "medium" # FO-Semantic MCP Server for D365 F&O [mcp_servers.fo-semantic] command = "npx" args = ["-y", "fo-semantic-mcp"] [mcp_servers.fo-semantic.env] FOINDEX_API_KEY = "your_api_key_here" FO_LOCAL_ASSETS_PATH = "C:\\Users\\YourName\\AppData\\Local\\Microsoft\\Dynamics365\\10.0.xxxx\\PackagesLocalDirectory" FO_SEARCH_DEFAULT_LIMIT = "10" FO_THRESHOLD = "0.7"

   Configuration Options

   FOINDEX_API_KEY (required) - Your API key from xplusplus.ai
   FO_LOCAL_ASSETS_PATH (recommended) - Path to your local F&O PackagesLocalDirectory for XML file reading
   FO_SEARCH_DEFAULT_LIMIT - Number of search results (default: 10)
   FO_THRESHOLD - Relevance threshold 0-1 (default: 0.5)

4. Restart Codex

   Save the config file and restart Codex CLI. The MCP server will be automatically downloaded and started via npx.

5. Test the Connection

   Try asking Codex to search for F&O artifacts:

   > List the F&O forms that involve CustTable

Example in Action

Here's what it looks like when Codex uses the MCP server to find F&O forms related to CustTable:

Codex automatically calls fo-semantic-mcp to search for forms involving CustTable, returning the full paths to each XML file.

Finding Your PackagesLocalDirectory

To enable local XML file reading, you need to set FO_LOCAL_ASSETS_PATH to your F&O installation:

Typical Windows path:

PowerShell command to find it:

Troubleshooting

MCP server not starting?

• Ensure Node.js 18+ is installed
• Check that npx is in your PATH
• Verify your API key is correct

No results returned?

• Try lowering the FO_THRESHOLD value (e.g., 0.5)
• Check your API key has available quota
• Try a simpler search query