ACP (Editor Integrations)

Xum implements the Agent Client Protocol (ACP) to integrate with editors that support it. The xum acp command starts a stdio bridge that any ACP-compatible editor can spawn as a subprocess.

ACP is the “LSP for agents” and provides session management, tool delegation, and streaming. Xum uses ACP (not MCP) for its editor bridge.

Zed

Zed has native ACP support and does not require a plugin. Open Settings (Cmd+,) and add:

{
  "agent_servers": {
    "Xum": {
      "type": "custom",
      "command": "xum",
      "args": ["acp"]
    }
  }
}

Using npx (no global install)

{
  "agent_servers": {
    "Xum": {
      "type": "custom",
      "command": "npx",
      "args": ["-y", "@coder/xum", "acp"]
    }
  }
}

Connect to a remote server

Pass --server-url and --auth-token in args:

{
  "agent_servers": {
    "Xum": {
      "type": "custom",
      "command": "xum",
      "args": ["acp", "--server-url", "https://xum.example.com", "--auth-token", "<token>"]
    }
  }
}

Or set environment variables for any xum acp process:

XUM_SERVER_URL=https://xum.example.com \
XUM_SERVER_AUTH_TOKEN=<token> \
xum acp

Neovim

Two plugins currently support ACP in Neovim.

codecompanion.nvim (recommended)

codecompanion.nvim added ACP support in v17.18. Add the adapter in your lazy.nvim config:

require("codecompanion").setup({
  adapters = {
    xum = function()
      return require("codecompanion.adapters").extend("acp", {
        name = "xum",
        schema = {
          model = { default = "xum" },
        },
        args = { "xum", "acp" },
      })
    end,
  },
  strategies = {
    chat = { adapter = "xum" },
    inline = { adapter = "xum" },
  },
})

See the codecompanion ACP adapter docs for full options.

agentic.nvim

agentic.nvim is a dedicated ACP client. Requires Neovim 0.11 or newer. Add via lazy.nvim:

{
  "carlos-algms/agentic.nvim",
  opts = {
    agents = {
      xum = {
        cmd = "xum",
        args = { "acp" },
      },
    },
  },
}

JetBrains

JetBrains ACP support requires the AI Assistant plugin (2025.3 or newer).

Open the AI Chat tool window
Click More (...) then Add Custom Agent
Add the Xum entry to the acp.json that opens:

{
  "agent_servers": {
    "Xum": {
      "command": "xum",
      "args": ["acp"]
    }
  }
}

ACP is not supported in WSL-backed JetBrains projects.

See the JetBrains ACP docs for more information.

Flags and environment variables

Flag	Environment variable	Description
`--server-url <url>`	`XUM_SERVER_URL`	URL of a running Xum server
`--auth-token <token>`	`XUM_SERVER_AUTH_TOKEN`	Bearer token for authenticated connections
`--log-file <path>`	—	Write ACP logs to a file (useful when your editor hides subprocess stderr)

XUM_AUTH_TOKEN is not read by xum acp. Use XUM_SERVER_AUTH_TOKEN.

If no --server-url is provided, xum acp first attempts to discover a running server via the lockfile in ~/.xum/, then starts an in-process server automatically when needed.

Troubleshooting

Logs hidden by your editor: use --log-file /tmp/xum-acp.log to capture ACP stderr output.
Connection refused: ensure Xum is running (xum server or the desktop app), or omit --server-url to let ACP auto-start in-process.
Tool calls are not delegated: the editor must advertise filesystem or terminal capabilities, and the workspace must use local runtime mode.

Getting Started

Workspaces

Agents

Configuration

Guides

Integrations

Reference

ACP (Editor Integrations)

Zed

Connect to a remote server

Neovim

codecompanion.nvim (recommended)

agentic.nvim

JetBrains

Flags and environment variables

Troubleshooting

​Zed

​Connect to a remote server

​Neovim

​codecompanion.nvim (recommended)

​agentic.nvim

​JetBrains

​Flags and environment variables

​Troubleshooting

​Related

Zed

Connect to a remote server

Neovim

codecompanion.nvim (recommended)

agentic.nvim

JetBrains

Flags and environment variables

Troubleshooting

Related