fastmcp/examples/smart_home/docs/usage.md

smart home setup and operation

Control Philips Hue lights and an Amazon Fire TV through FastMCP. Hue uses the phue2 1.0 alpha's local V2 API. Fire TV control reuses the androidtv backend shipped by Home Assistant's Android Debug Bridge integration; raw ADB shell access is not exposed to agents.

Design

This example is a local device-control server. An MCP client can discover devices, issue a command, and read back the result. It does not require Pi, a graphical picker, or a workflow engine.

• src/smart_home/hub.py mounts the independent Hue and Fire TV servers under hue and fire_tv namespaces.
• Each device package owns its connection lifespan, typed results, and tools.
• The optional media picker presents choices and calls the same playback tools over MCP.

Media search and recommendation belong to the calling agent or a discovery service. Schedules, presence policies, and durable desired state belong to the calling application or workflow engine. Device tools do not infer those policies.

Run

From the repository root, enter the example and install its dependencies (Python 3.12 or newer and uv are required):

cd examples/smart_home
uv sync

Create .env in this directory with your existing bridge credentials:

HUE_BRIDGE_IP=<bridge IP>
HUE_BRIDGE_USERNAME=<bridge application key>
HUE_BRIDGE_CERTIFICATE=/absolute/path/to/trusted-bridge.pem
FIRE_TV_HOST=<Fire TV IP>
FIRE_TV_ADB_SERVER_IP=127.0.0.1

HTTPS verification is enabled. The optional certificate file is an explicitly trusted certificate obtained and verified for your bridge; its identity replaces hostname matching when connecting by IP. Without it, normal system trust and hostname verification apply. Credentials remain local and are not saved by the SDK.

FIRE_TV_HOST is optional. When omitted, Hue tools continue to work and Fire TV tools return a configuration error. The example supports either an existing ADB server via FIRE_TV_ADB_SERVER_IP or direct Python ADB authentication via FIRE_TV_ADB_KEY. Enable ADB debugging and approve the host on the TV first.

uv run smart-home

This starts a stdio MCP server; configure your MCP client to run this command with this directory as its working directory. The combined hub requires Hue settings. For TV-only use, run the Fire TV server independently:

uv run fastmcp run src/smart_home/fire_tv/server.py:fire_tv_mcp --transport http --host 127.0.0.1 --port 8764

Standalone tools are named read_status and play_media; through the hub they are fire_tv_read_status and fire_tv_play_media. Use the standalone HTTP endpoint http://127.0.0.1:8764/mcp with the media picker's play_media configuration.

Each device server's lifespan owns its connection. Hue opens a pooled connection at startup; the Fire TV connects on the first tool call and reconnects after the TV drops off. Tools receive the connection through dependency injection. Settings load at startup, so importing the example does not require live credentials.

Agent workflow

TV and ad hoc media selection

Use fire_tv_read_status before and after fire_tv_press_home, fire_tv_launch_app, or fire_tv_play_youtube_video. App launch requires an exact installed package ID; YouTube playback requires an 11-character video ID. Commands return acceptance receipts, not proof that navigation completed. The constrained surface deliberately exposes neither arbitrary URLs nor raw ADB shell commands.

For a request such as "play a live bird camera where it is daylight": find a current feed, check the camera's location and local time, verify that the video is live and playable, then call fire_tv_play_youtube_video with its video ID. Use the broadcaster's current live page: old livestream links can return "recording is not available." This workflow does not require editing a catalog or adding a new tool for every video.

Status verifies the foreground app and broad playback state, not the video's identity, daylight, or audible content. Inspect the actual picture or obtain device media metadata when those details matter. A command receipt alone is not evidence that the requested stream is playing.

Hue rooms, scenes, and effects

Start with hue_read_rooms and hue_read_lights. Rooms include member light UUIDs; lights include state, device connectivity and supported effects. Names must match exactly and be unique. V2 UUIDs replace the old numeric light and group IDs.

To turn on candle flicker, check each room member's supported_effects and call hue_set_light for each supported bulb:

{
  "target": "<light UUID>",
  "state": {"on": true, "effect": "candle", "effect_speed": 0.5}
}

This preserves brightness. Read state.effect and state.effect_parameters afterward to verify the active effect; use effect: "no_effect" to stop it. Effect names and support come from the bulb, not a fixed list. Speed is between zero and one; color or temperature supplied with an active effect changes its parameters.

For ordinary room-wide lighting, use hue_set_room with brightness percent, temperature_kelvin, and optional transition_seconds. Color can instead use CIE xy coordinates. Native effects target individual bulbs. Brightness, color and effects do not implicitly turn lights on; include on: true when desired.

Use hue_read_scenes to inspect room associations, palettes and per-light actions. That distinguishes a scene with warm static colors from one with candle or fire effects. hue_activate_scene resolves names within the chosen room and recalls the saved actions. Its optional dynamic_palette action requests palette cycling where supported by Hue.

A write acknowledgement does not prove the resulting state. Read lights after a transition. Hue may partially apply a command before reporting an error; failures are exposed as MCP tool errors. This example does not implement scheduling, custom animation loops, or entertainment streaming.

Test with an agent

uv run pytest
uv run scripts/pi_harness.py --json

The tests exercise actual MCP calls with a simulated bridge. The Pi harness requires Pi and pi-mcp-adapter, exposes only this MCP, disables built-in tools, and defaults to read-only discovery. Pass --env-file /path/to/existing.env if credentials live elsewhere; HUE_BRIDGE_CERTIFICATE can also be exported in the launching environment. A quoted prompt may request real changes to lights. --json records tool calls and results for verification.

Discovery and result metadata

hue_read_lights(room="living room") and hue_read_scenes(room="living room") limit discovery to a room, using its exact unique name or UUID. Light results put observed state, supported effects and capabilities first. details=true includes the complete Hue light resource when needed. Unknown observations remain null; color temperature is reported only when Hue marks it valid.

hue_set_room exposes ordinary lighting controls only. Apply native effects with hue_set_light to each supported bulb. All writes return an accepted receipt with state_verified=false; read the affected room after a transition to verify state. Repeating an effect or scene command may restart its animation or transition, so write tools do not promise idempotence. Tools interact with the external bridge.

Connection troubleshooting

With the ADB-server transport, first check adb devices and connect with adb connect <Fire TV IP>:5555. If the TV is reachable but ADB reports a missing device, reconnect it.

On macOS, "No route to host" for a LAN address that ping and TCP reach from a terminal is Local Network privacy, not the network. A process inherits the permission of the app that launched it, so a server or ADB daemon started from an app without the grant (a tmux server, an editor) fails where the same command in a permitted terminal succeeds. Grant Local Network access to that app, or run the server on a Linux host on the same LAN.

The Fire TV connection opens on the first tool call, not at startup, so a TV that is asleep or off does not stop the server or the lights. A call made while the TV is unreachable fails with an error, and the next call reconnects.