Add a referral program with Windsurf

Give Windsurf the RefRef rules

The rules tell the agent where each part of a referral integration belongs: the landing script in the browser, one signup call where your backend creates the account, and the API key only on the server. Save it as .windsurf/rules/refref.md. Devin Desktop also reads .devin/rules.

Cascade reads workspace rules from .windsurf/rules (and .devin/rules after the rename). The RefRef rule uses trigger: model_decision with a description, so Cascade adds it when the task is about signup or referrals. A workspace rule can have at most 12,000 characters; the RefRef rules use about 4,500.

---
trigger: model_decision
description: "RefRef referral tracking: landing script, signup call at account creation, server-only API key. Use when you add or change signup, referral, or invite code."
---

# RefRef referral tracking

This app uses RefRef (https://refref.ai) for its referral program. Follow these rules when you add or change referral code.

## Configuration

- Server-only secrets: `REFREF_API_KEY` (a Workspace API key), `REFREF_PROJECT_ID`, and `REFREF_PROGRAM_ID`.
- `REFREF_API_URL` defaults to `https://api.refref.ai`, and `REFREF_ASSETS_URL` to `https://assets.refref.ai`. Read both from configuration, so that a Sandbox or local environment can change them.
- Never put `REFREF_API_KEY` in browser code, in a public variable (`NEXT_PUBLIC_*`, `VITE_*`), in a prompt, in a log, or in a commit.
- Every RefRef call is a backend `POST` with a JSON body that contains `projectId`, and the header `X-Api-Key`. The current schemas are at `GET $REFREF_API_URL/openapi`.

Or fetch it from the command line: curl -fsSL --create-dirs https://refref.ai/agents/windsurf/rules.md -o .windsurf/rules/refref.md

Connect Windsurf to RefRef MCP

Optional. With the MCP server, Windsurf can read your Workspaces, Projects, and Programs, and prepare configuration changes for you to approve in the Console. It never sends signups: that is the app code from the rules. See the MCP reference for scopes and approvals.

Configuration: ~/.config/devin/mcp_config.json (formerly ~/.codeium/windsurf/mcp_config.json)

{
  "mcpServers": {
    "refref": {
      "serverUrl": "https://mcp.refref.ai/mcp"
    }
  }
}

Sign in

Open the MCP panel in Cascade, refresh, and connect refref. Sign in with your RefRef Console account in the browser. The connection uses your Console sign-in, never a Workspace API key.

Check it

The Cascade MCP panel lists refref and its tools.

• Cascade can use at most 100 tools in total across servers. Turn off tools you do not need.
• On Team and Enterprise plans, an admin allowlist can block servers that it does not name.
• A workspace rule file can have at most 12,000 characters. The RefRef rules use about 4,500.