# Setup MCP Server > Add mcp-rubber-duck MCP server to an AI coding tool (Claude Desktop, Cursor, VS Code, Windsurf, etc.) Use when this capability is needed. - Skill: `tomevault-io/setup-mcp-server` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/setup-mcp-server` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/setup-mcp-server/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: AI & ML - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/setup-mcp-server --- # Setup mcp-rubber-duck You are setting up **mcp-rubber-duck** as an MCP server in an AI coding tool. ## Reference - `.claude/skills/setup-mcp-server/references/tool-configs.md` — per-tool JSON/YAML config templates - `.claude/skills/setup-mcp-server/references/provider-env-vars.md` — env var reference - `.claude/skills/setup-mcp-server/references/troubleshooting.md` — common issues ## Supported tools and config paths | Tool | Config File (macOS) | Key | Notes | |------|-------------------|-----|-------| | Claude Desktop | `~/Library/Application Support/Claude/claude_desktop_config.json` | `mcpServers` | Windows: `%APPDATA%\Claude\claude_desktop_config.json` | | Claude Code (user) | `~/.claude.json` | `mcpServers` | Prefer `claude mcp add` CLI | | Claude Code (project) | `.mcp.json` | `mcpServers` | Shared via VCS | | Cursor (project) | `.cursor/mcp.json` | `mcpServers` | | | Cursor (global) | `~/.cursor/mcp.json` | `mcpServers` | | | Windsurf | `~/.codeium/windsurf/mcp_config.json` | `mcpServers` | Supports `${env:VAR}` | | VS Code | `.vscode/mcp.json` | `servers` | Different key name! Uses `${env:VAR}` | | Continue | `.continue/config.yaml` | `mcpServers` (array) | YAML format | ChatGPT supports MCP via UI only (Developer Mode > Add MCP Server), not a config file. ## 1. Determine target tool If `$ARGUMENTS` specifies a tool name, use it. Otherwise ask the user: Supported tools: `claude-desktop`, `claude-code`, `cursor`, `windsurf`, `vscode`, `continue` ## 2. Detect platform Run `uname -s` to detect macOS / Linux / Windows (Git Bash). This affects config file paths. ## 3. Detect install method Check in order: 1. `which mcp-rubber-duck` — if found, use `mcp-rubber-duck` as the command 2. If we're inside the mcp-rubber-duck repo (check for `package.json` with `"name": "mcp-rubber-duck"`), offer from-source via `node dist/index.js` 3. Default to `npx -y mcp-rubber-duck` ## 4. Ask about providers Ask the user which providers to include. Offer these choices: - **OpenAI** (`OPENAI_API_KEY`) — most popular - **Google Gemini** (`GEMINI_API_KEY`) - **Groq** (`GROQ_API_KEY`) — fast inference - **Ollama** (local, no key needed) - **CLI agents** (Claude CLI, Codex, Gemini CLI, Aider) Allow multiple selections. ## 5. Ask about API keys For each selected HTTP provider that needs a key, ask: **provide a real key now** or **use a placeholder** to fill in later? - If real key: validate it looks reasonable (starts with expected prefix like `sk-` for OpenAI, `gsk_` for Groq) - If placeholder: use descriptive placeholders like `your-openai-api-key-here` ## 6. Load reference templates Read the config template from `.claude/skills/setup-mcp-server/references/tool-configs.md` to get the exact JSON/YAML structure for the target tool. ## 7. Write the configuration ### For Claude Code (`claude-code`) Use the `claude mcp add` CLI command — this is the idiomatic way: ```bash claude mcp add --scope user rubber-duck -- mcp-rubber-duck ``` Then set env vars by editing `~/.claude.json` to add the `env` block, or suggest the user set them in their shell profile. If the user prefers project-scope, use `--scope project` (writes to `.mcp.json`). ### For all other tools 1. Determine the config file path (platform-aware) from the reference templates 2. Read the existing config file if it exists 3. If `rubber-duck` entry already exists, **warn the user** and ask before overwriting 4. If other MCP servers exist, **merge** — never overwrite the entire file 5. If the file doesn't exist, create it (and parent directories with `mkdir -p`) 6. If existing JSON is invalid, warn and offer to backup the broken file before writing 7. Write the final config ### Important details - **Always** include `"MCP_SERVER": "true"` in the env block — this is required - **VS Code** uses `"servers"` key, not `"mcpServers"` — get this right - **Continue** uses YAML with `mcpServers` as an array of objects - **Windsurf & VS Code** support `${env:VAR_NAME}` syntax for env var interpolation ## 8. Print verification steps After writing the config, tell the user: 1. **Restart** the tool (fully quit and relaunch for desktop apps) 2. **Test** by using the `list_ducks` tool with `check_health: true` 3. **Troubleshoot** — point them to `.claude/skills/setup-mcp-server/references/troubleshooting.md` if anything goes wrong ## Important rules - Never overwrite existing MCP server entries for other servers - Always create parent directories before writing config files - Use the exact JSON structure from the reference templates - For env var interpolation tools (VS Code, Windsurf), prefer `${env:VAR}` syntax over hardcoded keys - Include `DEFAULT_PROVIDER` set to the first selected HTTP provider --- > Source: [nesquikm/mcp-rubber-duck](https://github.com/nesquikm/mcp-rubber-duck) — distributed by [TomeVault](https://tomevault.io).