> ## Documentation Index > Fetch the complete documentation index at: https://docs.symmetry.com/llms.txt > Use this file to discover all available pages before exploring further. # STE MCP installation > Install and connect the Symmetry Tax Engine Model Context Protocol (MCP) server in Cursor, Claude Code, Gemini CLI, or Claude Desktop. This guide walks through installing and connecting the [Symmetry Tax Engine (STE) MCP server](/ste/ai-interfaces/mcp-overview) in each supported client. For what the MCP can do and example prompts, see the [STE MCP overview](/ste/ai-interfaces/mcp-overview). ## Prerequisites 1. Active STE license 2. One of the supported AI apps installed on your computer (see below) **Don't have an AI app yet? Pick one to get started.** All four options below are free to download. If you're not sure which to choose, **Claude Desktop** is the easiest starting point for non-technical users. It installs like any desktop app and requires no command line. [See a walkthrough](/ste/ai-interfaces/connect-claude-desktop). | Tool | Best for | Download | | -------------- | --------------------------------------------- | ---------------------------------------------------------------------------------- | | Claude Desktop | Easiest setup; no technical experience needed | [claude.ai/download](https://claude.ai/download) | | Cursor | Users who work in or alongside code | [cursor.com/downloads](https://www.cursor.com/downloads) | | Claude Code | Terminal-comfortable users | [Install guide](https://docs.claude.com/en/docs/claude-code/overview) | | Gemini CLI | Users already in the Google ecosystem | [github.com/google-gemini/gemini-cli](https://github.com/google-gemini/gemini-cli) | ## Installation Add one MCP server entry to your assistant. The first time you use a tool, your browser will open and prompt you to log in using your Symmetry Client Support Center credentials. **Method A: Settings UI** Press `Cmd+,` (macOS) or `Ctrl+,` (Windows/Linux) to open Settings. Click **MCP** in the left sidebar, then **Add MCP Server**. * **Name:** `ste` * **URL:** `https://mcp.symmetry.com/ste` * Leave Transport on the default (Streamable HTTP) The server will appear with a green dot once Cursor connects successfully. **Method B: Edit `~/.cursor/mcp.json`** If the file doesn't exist yet, create it. Add: ```json theme={null} { "mcpServers": { "ste": { "url": "https://mcp.symmetry.com/ste" } } } ``` If you already have other MCP servers configured, add `ste` as a new key inside the existing `mcpServers` object—don't replace the whole file! For example, a file with two servers looks like: ```json theme={null} { "mcpServers": { "some-other-server": { "url": "https://example.com/mcp" }, "ste": { "url": "https://mcp.symmetry.com/ste" } } } ``` Save the file. Cursor picks up the change automatically; no restart needed. Run this command in your terminal: ```text theme={null} claude mcp add ste --transport http https://mcp.symmetry.com/ste --callback-port 33418 ``` **Restart Claude Code after running the command.** Claude Code only loads MCPs at startup—exit your current session and open a new one. To verify, run: ```text theme={null} claude mcp list ``` You should see `ste` in the output. **Why `--callback-port 33418`?** Symmetry's OAuth allowlist only accepts port 33418 as a redirect target. Claude Code picks a random ephemeral port by default, which causes a `redirect_mismatch` error. Pinning the port fixes this. Cursor uses 33418 by default, so no flag is needed there. Edit `~/.gemini/settings.json` and add the following under `mcpServers`: ```json theme={null} { "mcpServers": { "ste-mcp": { "httpUrl": "https://mcp.symmetry.com/ste", "oauth": { "enabled": true, "redirectUri": "http://localhost:33418/oauth/callback" } } } } ``` Always set `redirectUri` explicitly. If omitted, Gemini CLI may choose a random port that fails authentication. Open **Customize** from the left sidebar on the home screen. Select the **Connectors** tab on the left. Click the `+` button (next to the search icon) at the top of the Connectors panel, then choose **Add custom connector**. * Name: `ste` * URL: `https://mcp.symmetry.com/ste` * Leave the OAuth Client ID and OAuth Client Secret fields blank — they're optional and not needed here. Click **Add**. The `ste` connector now appears under **Not connected**, tagged `CUSTOM`. Select it, then click **Connect**. Your browser will open and prompt you to log in using your Symmetry Client Support Center credentials. Start a new chat and ask: ```text theme={null} use the ste mcp to get the ste version ``` Verify the response looks like the following: ```text theme={null} The STE deployment reports: STE version: 2026.6.2 Release: 1.173.2127 (major 1, minor 173, revision 2127) ``` Prefer to watch it done first? See [Connect Claude Desktop to the STE MCP Demo](/ste/ai-interfaces/connect-claude-desktop). ## Verify the connection The easiest test is `ste_get_version`. It confirms auth, transport, and the STE engine are all working. In any supported client, ask: ```text theme={null} use the ste mcp to get the ste version ``` The first time, your browser will open for Symmetry sign-in. After authenticating using your Client Support Center credentials, the client will display a version string like `2026.4.3.7-SNAPSHOT`. Subsequent calls in the same session reuse the cached token—no more browser prompts. ## Next steps * New to what the MCP can do? See the [STE MCP overview](/ste/ai-interfaces/mcp-overview) for the full tool list and sample prompts. * Prefer a video walkthrough for Claude Desktop? See [Connect Claude Desktop to the STE MCP Demo](/ste/ai-interfaces/connect-claude-desktop). * Running into issues? See [STE MCP Troubleshooting](/ste/ai-interfaces/mcp-troubleshooting).