MCP

chime mcp serve runs a standard Model Context Protocol server over stdio (JSON-RPC 2.0). It’s the portable integration layer: any MCP-capable agent host can call it, not just Claude Code.

The six tools

`chime_status`

Current daemon status: paired state, machine routing id, peer routing id, relay URL, and registered aliases. No input.

`chime_setup`

Onboarding helper. Reports whether the daemon is running and the machine is paired, and returns the exact next step (e.g. “run chime pair and scan the QR”). Also where you choose a session alias: pass an optional human-friendly alias (e.g. "auth-refactor") — normalized to a [a-z0-9-] slug — to use for every send this session. Single-identity agents should reuse one stable alias across sessions; omit it to keep the friendly auto-generated default.

Field	Type	Required
`alias`	string	no

`chime_notify`

Sends a notification to the paired phone: a ping, an approval card, an ack, freeform text, or a rich A2UI card.

Field	Type	Required	Notes
`message`	string	yes	Message text (also the title for approval/ui cards).
`alias`	string	no	Usually omit — defaults to the session alias. The phone groups threads by working directory + harness + model, not by alias.
`kind`	`ping` \| `approval` \| `ack` \| `text` \| `ui`	no	Default `ping`.
`options`	string[]	no	Choice labels for `approval`; the mandatory plain-text fallback for `ui`.
`surface`	object	no	An A2UI surface (declarative UI-as-data — Card/Column/Row/Text/Button/ChoicePicker) for `kind: ui`. Rendered natively on the phone, never executed as code.
`reply_to`	string	no	A relay message id this notification replies to — the phone shows a quoted snippet above it, visually threading the reply.

`chime_receive`

Non-blocking drain of currently queued inbound messages for an alias. Returns immediately with whatever’s waiting — nothing if the queue is empty.

Field	Type	Required
`alias`	string	no — defaults to the session alias

`chime_wait`

Blocks until the next inbound message arrives for the alias, or until timeout_secs elapses. This is the “wait for the human’s approval/reply” primitive to call right after chime_notify sends an approval or question.

Field	Type	Required	Notes
`alias`	string	no	Defaults to the session alias.
`timeout_secs`	number	no	Default 300.

`chime_reply`

Convenience wrapper: replies to the most recently received message’s alias. Sends an approval response if choice is given, otherwise a text/ack. Alias and kind are derived from context automatically.

Field	Type	Required	Notes
`choice`	string	no	The option label chosen, for approval replies.
`message`	string	no	Freeform text, for text/ack replies.
`alias`	string	no	Defaults to the last-received alias, then the session alias.
`reply_to`	string	no	The specific inbound message id being replied to; the phone shows a quoted snippet of it.

Configure

Claude Code

The zero-build path — chime mcp install writes the config for you (see Install — run this yourself after installing the CLI, the install script doesn’t run it for you):

chime mcp install            # writes ./.mcp.json (project-scoped)
chime mcp install --global   # writes ~/.claude.json (user-scoped)

Or register it directly with Claude Code’s own CLI:

claude mcp add chime -- chime mcp serve

Both produce the same shape, an mcpServers entry running chime mcp serve:

{
  "mcpServers": {
    "chime": {
      "command": "chime",
      "args": ["mcp", "serve"]
    }
  }
}

Any other MCP host

Same JSON shape, a stdio server invoking chime mcp serve — only the config file path and dialect differ per host (~/.cursor/mcp.json, ~/.codeium/windsurf/mcp_config.json, ~/.gemini/settings.json mcpServers, ~/.kimi/mcp.json, etc.):

{
  "mcpServers": {
    "chime": {
      "command": "chime",
      "args": ["mcp", "serve"],
      "env": { "CHIME_HOME": "~/.chime-<harness>" }
    }
  }
}

The optional CHIME_HOME override keeps each harness’s identity/session state in its own directory, so running several harnesses on one machine doesn’t collide.

CLI — the shell-only equivalent of every MCP tool above.
Quickstart — install, pair, first message.

MCP

The six tools

chime_status

chime_setup

chime_notify

chime_receive

chime_wait

chime_reply