Cursor IDE Setup

Connect Cursor to Nexus-Catalyst for persistent memory across your development sessions.

Overview

Cursor supports MCP (Model Context Protocol) servers natively. Once connected, Cursor’s AI can:

• Recall prior sessions — decisions, fixes, and context from past work, in any project
• Search your memory store mid-session with search_memories
• Store new context at the end of a session with store_context
• Load personas — specialized AI personalities like Jack (architecture) or Nora (documentation)

Prerequisites

• Cursor with MCP support — download from cursor.com
• A Nexus-Catalyst account with an active subscription or trial — start a 14-day trial, or use your invitation if you have one

No API key is required — the NC MCP server uses OAuth, and Cursor opens a browser window so you can sign in with your NC account.

Setup

Step 1: Add the MCP server

In Cursor: Agent Settings → Customize → MCPs tab → New MCP Server.

That does not open a form — it opens mcp.json directly, at ~/.cursor/mcp.json (global) or in a project root for project-only access. Add an entry under mcpServers:

~/.cursor/mcp.json

{
  "mcpServers": {
    "nexus-catalyst": {
      "url": "https://mcp.nexus-catalyst.com/"
    }
  }
}

The key (nexus-catalyst) is just the label Cursor shows you — name it whatever you like. The url is the only required field: no API key, no bearer token, no transport setting. Anything asking you to paste a token is out of date.

Step 2: Authenticate

Save the file and Cursor picks the server up. It appears in the MCPs tab with a login prompt — click it, and your browser opens the Nexus-Catalyst sign-in page. Sign in (email/password, Google, or GitHub) and approve access.

Step 3: Verify the connection

Back in the MCPs tab, the entry should show a green status with the available tools listed:

• recall_context
• store_context
• search_memories
• get_memory_detail
• get_persona_definition
• update_user_facts
• integration_query
• integration_mutate

Clicking the entry opens its configure panel, where each tool can be toggled individually — leave them all enabled:

Step 4: Test memory recall

Open Cursor’s AI chat and ask:

What do you remember about my current project? Use recall_context.

If you’ve stored memories before, the response will reference them. If this is a fresh account, store one first:

Store a memory that I prefer TypeScript strict mode in all new projects.

Note

Model Context Protocol covers the client side of MCP in more depth than this page does.

Using Nexus-Catalyst in Cursor

Natural-language memory

You don’t need to name tools — just ask naturally and the model picks the right one:

• “How did we handle rate limiting in the API project?” → recall_context / search_memories
• “Pull up the full write-up of that auth fix” → get_memory_detail
• “Remember that we’re standardizing on Prisma for this repo” → store_context

Personas

When recall_context returns a persona_hint, the model loads that persona via get_persona_definition. You can also ask for one by name — for example Jack (AI engineering/architecture), Betty (UX), Ed (product), or Nora (technical writing). See the full roster in Personas.

Linear from chat

With a Linear integration configured, you can create and search issues without leaving Cursor — “Create a Linear issue for this CORS bug.” See Linear Integration.

Troubleshooting

Server shows “not connected”

1. Check the URL is exactly https://mcp.nexus-catalyst.com (no trailing path)
2. Re-trigger the OAuth flow from Agent Settings → Customize → MCPs — sessions can expire
3. Confirm the server is reachable:

   curl https://mcp.nexus-catalyst.com/.well-known/oauth-protected-resource

Tools listed but calls fail with 401

Your OAuth session expired. Remove and re-add the server, or use the login prompt in Agent Settings → Customize → MCPs to re-authenticate.

Memory not recalled

1. Verify memories exist in the dashboard
2. Use a specific query — “what database did we choose for the e-commerce project” beats “what did we discuss”
3. Ask explicitly: “call recall_context for this topic”

What’s Next?

• Claude Code Setup → — CLI + hook plugin
• MCP Tools Reference → — all NC tools
• Linear Integration → — issue tracking

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Need Help?

• Common Issues
• Contact Support

Next: tell Cursor to use it

Connecting the server exposes the tools; it does not make Cursor call them. Add the MCP Instructions as a Cursor rule so recall and storage happen on their own.