Add LittleGuy to your favorite agents

Claude Desktop

Customize > Connectors > + Add > Add custom connector. Paste this URL, choose automatic registration if offered, then connect and sign in to LittleGuy. The remote connector runs from Anthropic's cloud.

https://mcp.littleguy.app/mcp?profile=claude_desktop

Claude Code

Terminal. Run this command. In Claude Code, use /mcp to authorize LittleGuy.

claude mcp add --transport http --scope user littleguy 'https://mcp.littleguy.app/mcp?profile=claude_code'

Codex

Terminal. Run the add command, then run codex mcp login littleguy to authorize it.

codex mcp add littleguy --url 'https://mcp.littleguy.app/mcp?profile=codex'
codex mcp login littleguy

ChatGPT

Settings > Apps > Create app (developer mode). Add LittleGuy with this MCP URL and OAuth authentication, then connect it. Developer mode availability depends on your plan and workspace.

https://mcp.littleguy.app/mcp?profile=chatgpt

Choose OAuth when creating the app. After a server tool change, refresh the app's tool schema and republish the workspace app if applicable. Reconnecting alone can leave the old catalog cached.

Cursor

.cursor/mcp.json. Open the install link or merge this config into your MCP settings, then authorize LittleGuy.

{
  "mcpServers": {
    "littleguy": {
      "url": "https://mcp.littleguy.app/mcp?profile=cursor"
    }
  }
}

For all projects, put this in ~/.cursor/mcp.json. For one project, use .cursor/mcp.json.

OpenCode

opencode.json. Merge this config, then run opencode mcp auth littleguy.

{
  "mcp": {
    "littleguy": {
      "type": "remote",
      "url": "https://mcp.littleguy.app/mcp?profile=opencode",
      "enabled": true
    }
  }
}

opencode mcp auth littleguy

First-use check

1. Ask: “Use LittleGuy to remember this test note: my connection test color is violet. Record this request as the source.” Check that a memory ID was returned.
2. Ask: “Recall my connection test color.” Check the returned ID, content and source. A chat answer alone does not prove retrieval.
3. Ask: “Use memory-get on that ID, then retract this test note with memory-update. Reason: connection test finished.” It stays in history and should disappear from active recall.
4. Ask: “What projects am I working on?” or “My tasks”. You can narrow recall with scope.nodeTypes set to Project or Task. No results can mean there are no current records of that type.

If something fails

The updated default catalog has six tools: remember, recall, get, update, relate and brief. If you still see four, refresh the client's tool list and start a new connection; in ChatGPT, refresh its app schema too. Advanced tools remain optional with tools=advanced in the URL.

For an expired or revoked grant, disconnect LittleGuy in the client and authorize again. In Codex, run codex mcp login littleguy; in Claude Code, use /mcp; in OpenCode, run opencode mcp auth littleguy. Check account identity and workspace policy if memories are missing. Remote Claude connectors need a public HTTPS endpoint, not localhost.

If remember asks about duplicate candidates, inspect the returned IDs with memory-get. Ask the user which candidate to use. Use memory-update with operation attach to retain the selected record and add the new source, or repeat remember with onAmbiguity create_new. Edits create a sourced replacement; retract and restore retain history. Delegated tokens cannot use get or update.

What has been verified

Earlier native Codex testing completed OAuth, tool listing, save and recall on the four-tool release. OpenCode, Cursor and Gemini have partial native connection evidence. Claude Desktop, Claude Code and ChatGPT instructions have protocol support, but native save-and-recall testing remains outstanding. These instructions do not certify those clients or the updated six-tool catalog in production.

LittleGuy supports remote HTTP MCP with public-client registration, OAuth and S256 PKCE. Client availability depends on your plan, installed version and workspace settings. Setup uses the client's own login flow; never paste access tokens into a chat or shared configuration.