# AGS Extend SDK MCP Server
This **Model Context Protocol (MCP) server** exposes Extend SDK functions and models as additional context to language models. It helps AI coding assistants and other MCP clients to answer questions and generate Extend SDK code by providing the following tools.
- **`search-symbols`** – Search for symbols (functions and models) by name, tags, description (fuzzy)
- **`describe-symbols`** – Get detailed information about specific symbols by their IDs
- **`create-extend-app`** – Prompt template for creating Extend app projects
## Quickstart
### Prerequisites
- [Cursor](https://cursor.com/home)
- Docker
> [!NOTE]
> The instructions below can be adapted for other MCP clients as well e.g. Claude Desktop, Gemini CLI, and Visual Studio Code.
### Alternative 1: Using STDIO transport (default)
1. Pull the AGS Extend SDK MCP Server container image. For example, with image tag 2026.1.0.
```bash
docker pull ghcr.io/accelbyte/ags-extend-sdk-mcp-server:2026.1.0
```
2. Switch to your project directory and create `.cursor/mcp.json` with the following content.
```json
{
"mcpServers": {
"extend-sdk-mcp-server": {
"command": "docker",
"args": [
"run",
"-i",
"--rm",
"-e",
"CONFIG_DIR",
"ghcr.io/accelbyte/ags-extend-sdk-mcp-server:2026.1.0"
],
"env": {
"CONFIG_DIR": "config/go"
}
}
}
}
```
The `CONFIG_DIR` value above is for Go Extend SDK. For other Extend SDK languages, see [here](#environment-variables).
3. Open your project directory in Cursor and open `File` > `Preferences` > `Cursor Settings`, In `Cursor Settings`, click `MCP`, and make sure `extend-sdk-mcp-server` is enabled.
### Alternative 2: Using Streamable HTTP transport
1. Pull the AGS Extend SDK MCP Server container image. For example, with image tag 2026.1.0.
```bash
docker pull ghcr.io/accelbyte/ags-extend-sdk-mcp-server:2026.1.0
```
2. Start the MCP server with streamable HTTP transport.
```bash
docker run -p 3000:3000 \
-e TRANSPORT=http \
-e PORT=3000 \
-e CONFIG_DIR=config/go \
-e NODE_ENV=production \
-e LOG_LEVEL=info \
ghcr.io/accelbyte/ags-extend-sdk-mcp-server:2026.1.0
```
The `CONFIG_DIR` value above is for Go Extend SDK. For other Extend SDK languages, see [here](#environment-variables).
3. Switch to your project directory and create `.cursor/mcp.json` with the following content.
```json
{
"mcpServers": {
"extend-sdk-mcp-server": {
"url": "http://localhost:3000/"
}
}
}
```
4. Open your project directory in Cursor and open `File` > `Preferences` > `Cursor Settings`, In `Cursor Settings`, click `MCP`, and make sure `extend-sdk-mcp-server` is enabled.
> [!IMPORTANT]
> Use the `ghcr.io/accelbyte/ags-extend-sdk-mcp-server` image tag that matches your AGS version. See the available image tags [here](https://github.com/accelbyte/ags-extend-sdk-mcp-server/pkgs/container/ags-extend-sdk-mcp-server/versions).
### Sample prompts
In Cursor, press `CTRL+L` and try the following prompts. You should see that the tools provided by this MCP server are used. Give permission to execute the tools when requested.
- Search symbols: `Search for symbols related to 'user'`
- Get symbol details: `Describe the 'AdminCreateUser@iam' and 'User@iam' symbols`
[!TIP] When coding using this MCP server, we recommend to start from an Extend SDK getting started sample project or an Extend app template project instead of a blank project. Add the necessary context, such as specific source code files, to help getting better results.
## Environment Variables
- `TRANSPORT`: The MCP server transport (valid values: `stdio`, `http`, `streamableHttp`, default: `stdio`)
- `PORT`: HTTP server port if `TRANSPORT` is `http` (default: `3000`)
- `CONFIG_DIR`: Directory of YAML config files (recursive, default: `config/go`)
- For Extend SDK C#: `config/csharp`
- For Extend SDK Go: `config/go`
- For Extend SDK Java: `config/java`
- For Extend SDK Python: `config/python`
- `LOG_LEVEL`: Logging level (valid values: `debug`, `info`, `warn`, `error`, default: `info`)
- `ALLOWED_ORIGINS`: Comma-separated list of allowed origins for HTTP transport (optional)
- `NODE_ENV`: Environment (valid values: `development`, `production`) (optional, used by Express for HTTP transport)
## Development
### Prerequisites
- Bash
- Curl
- Docker
- Makefile
- Node.js 18+
- pnpm
### Install dependencies
```bash
pnpm install
```
### Start the MCP server for development
#### With the default STDIO transport
```bash
pnpm dev
```
#### With streamable HTTP transport
```bash
TRANSPORT=http pnpm dev
```
### Build the MCP server
```bash
pnpm build
```
### Start the MCP server after build
#### With the default STDIO transport
```bash
pnpm start
```
#### With streamable HTTP transport
```bash
TRANSPORT=http pnpm start
```
### Build the MCP server container image
```bash
docker build -t extend-sdk-mcp-server:latest .
```
## Release
### Push the MCP server container image to container registry
```bash
# Setup variables
GHCR_USERNAME=<your-username>
GHCR_PASSWORD=<your-password>
IMAGE_TAG=2026.1.0 # Matches AGS release, bump patch version for hotfix
# Prepare builder
docker buildx inspect extend-sdk-mcp-server-builder || docker buildx create --name extend-sdk-mcp-server-builder --use
# Login, build, and push multiarch image
docker login --username ${GHCR_USERNAME --password $GHCR_PASSWORD}
docker buildx build -t ghcr.io/accelbyte/ags-extend-sdk-mcp-server:${IMAGE_TAG} --platform linux/amd64,linux/arm64 --push .
# Clean up builder
docker buildx rm --keep-state extend-sdk-mcp-server-builder
```
## Testing
1. Start the MCP server with HTTP transport.
2. Initialize the MCP connection.
```bash
curl -N -H "Accept: application/json, text/event-stream" \
-H "Content-Type: application/json" \
-X POST \
-d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2024-11-05","capabilities":{},"clientInfo":{"name":"test-client","version":"1.0.0"}}}' \
http://localhost:3000/
```
3. List available tools.
```bash
curl -N -H "Accept: application/json, text/event-stream" \
-H "Content-Type: application/json" \
-X POST \
-d '{"jsonrpc":"2.0","id":2,"method":"tools/list","params":{}}' \
http://localhost:3000/
```
4. Test the search tool.
```bash
curl -N -H "Accept: application/json, text/event-stream" \
-H "Content-Type: application/json" \
-X POST \
-d '{"jsonrpc":"2.0","id":3,"method":"tools/call","params":{"name":"search-symbols","arguments":{"query":"user"}}}' \
http://localhost:3000/
```
5. Test describe model.
```bash
curl -N -H "Accept: application/json, text/event-stream" \
-H "Content-Type: application/json" \
-X POST \
-d '{"jsonrpc":"2.0","id":4,"method":"tools/call","params":{"name":"describe-symbols","arguments":{"ids":["User@iam"]}}}' \
http://localhost:3000/
```
