From ef096a236f12d8523f12c37c0dcb6992c6eacc5d Mon Sep 17 00:00:00 2001
From: andig <andi@evcc.io>
Date: Sun, 23 Nov 2025 10:49:39 +0100
Subject: [PATCH] HomeAssistant: add auto-discovery (#25141)

---
 api/globalconfig/types.go                     |  8 +-
 assets/css/app.css                            | 30 +++++++
 .../Config/DeviceModal/DeviceModalBase.vue    | 38 ++++++++-
 .../Config/DeviceModal/index.test.ts          | 54 +++++++++++++
 .../js/components/Config/DeviceModal/index.ts | 71 ++++++++++++++++
 assets/js/components/Config/PropertyEntry.vue |  2 +
 assets/js/components/Config/PropertyField.vue | 52 +++++++++---
 assets/js/utils/placeholder.test.ts           | 26 ++++++
 assets/js/utils/placeholder.ts                | 20 +++++
 charger/homeassistant-switch.go               | 15 ++--
 charger/homeassistant.go                      | 11 ++-
 cmd/root.go                                   |  7 ++
 meter/homeassistant.go                        |  8 +-
 package-lock.json                             |  2 +-
 package.json                                  |  2 +-
 push/hub.go                                   | 10 +--
 server/http.go                                |  4 +
 server/network/registry.go                    | 33 ++++++++
 server/service/registry.go                    | 36 +++++++++
 .../charger/homeassistant-switch.yaml         | 26 +++---
 templates/definition/meter/homeassistant.yaml | 32 +++++---
 .../definition/vehicle/homeassistant.yaml     | 41 +++++-----
 util/homeassistant/connection.go              | 42 +++++-----
 util/homeassistant/instance.go                | 23 ++++++
 util/homeassistant/oauth2.go                  | 54 +++++++++++++
 util/homeassistant/proxy.go                   | 44 ++++++++++
 util/homeassistant/service.go                 | 81 +++++++++++++++++++
 util/homeassistant/types.go                   | 11 +++
 util/homeassistant/zeroconf.go                | 73 +++++++++++++++++
 util/templates/types.go                       |  1 +
 vehicle/homeassistant.go                      | 26 +++---
 31 files changed, 764 insertions(+), 119 deletions(-)
 create mode 100644 assets/js/components/Config/DeviceModal/index.test.ts
 create mode 100644 assets/js/utils/placeholder.test.ts
 create mode 100644 assets/js/utils/placeholder.ts
 create mode 100644 server/network/registry.go
 create mode 100644 server/service/registry.go
 create mode 100644 util/homeassistant/instance.go
 create mode 100644 util/homeassistant/oauth2.go
 create mode 100644 util/homeassistant/proxy.go
 create mode 100644 util/homeassistant/service.go
 create mode 100644 util/homeassistant/types.go
 create mode 100644 util/homeassistant/zeroconf.go

diff --git a/api/globalconfig/types.go b/api/globalconfig/types.go
index 81f230bcc..e45ea26b3 100644
--- a/api/globalconfig/types.go
+++ b/api/globalconfig/types.go
@@ -11,7 +11,6 @@ import (
 	"github.com/evcc-io/evcc/api"
 	"github.com/evcc-io/evcc/hems/shm"
 	"github.com/evcc-io/evcc/plugin/mqtt"
-	"github.com/evcc-io/evcc/push"
 	"github.com/evcc-io/evcc/server/eebus"
 	"github.com/evcc-io/evcc/util"
 	"github.com/evcc-io/evcc/util/config"
@@ -137,10 +136,15 @@ type DB struct {
 }
 
 type Messaging struct {
-	Events   map[string]push.EventTemplateConfig
+	Events   map[string]MessagingEventTemplate
 	Services []config.Typed
 }
 
+// MessagingEventTemplate is the push message configuration for an event
+type MessagingEventTemplate struct {
+	Title, Msg string
+}
+
 func (c Messaging) Configured() bool {
 	return len(c.Services) > 0 || len(c.Events) > 0
 }
diff --git a/assets/css/app.css b/assets/css/app.css
index fa1d2ed02..510d802aa 100644
--- a/assets/css/app.css
+++ b/assets/css/app.css
@@ -584,6 +584,36 @@ input[type="time"]::-webkit-calendar-picker-indicator {
 	display: none;
 }
 
+input[list]::-webkit-list-button {
+	display: none !important;
+	appearance: none !important;
+}
+
+.form-control-clear {
+	position: absolute;
+	right: 0.75rem;
+	top: 0;
+	bottom: 0;
+	justify-content: center;
+	display: flex;
+	align-items: center;
+	justify-self: center;
+	width: 1.1rem;
+	font-size: 1.5rem;
+	font-weight: normal;
+	color: var(--evcc-default-text);
+	border: none;
+	background-color: transparent;
+	padding: 0;
+	margin: 0;
+	cursor: pointer;
+}
+
+/* hide dropdown arrow if clear is visible */
+.form-select.has-clear-button {
+	background-image: none;
+}
+
 .table {
 	--bs-table-bg: transparent;
 }
diff --git a/assets/js/components/Config/DeviceModal/DeviceModalBase.vue b/assets/js/components/Config/DeviceModal/DeviceModalBase.vue
index 2f216e07d..b094d016b 100644
--- a/assets/js/components/Config/DeviceModal/DeviceModalBase.vue
+++ b/assets/js/components/Config/DeviceModal/DeviceModalBase.vue
@@ -52,6 +52,7 @@
 							:key="param.Name"
 							v-bind="param"
 							v-model="values[param.Name]"
+							:service-values="serviceValues[param.Name]"
 						/>
 						<p v-if="authError" class="text-danger">{{ authError }}</p>
 						<div class="d-flex justify-content-end">
@@ -109,6 +110,7 @@
 							:key="param.Name"
 							v-bind="param"
 							v-model="values[param.Name]"
+							:service-values="serviceValues[param.Name]"
 						/>
 
 						<PropertyCollapsible>
@@ -119,6 +121,7 @@
 									:key="param.Name"
 									v-bind="param"
 									v-model="values[param.Name]"
+									:service-values="serviceValues[param.Name]"
 								/>
 							</template>
 							<template v-if="$slots['collapsible-more']" #more>
@@ -160,7 +163,7 @@ import { initialTestState, performTest } from "../utils/test";
 import sleep from "@/utils/sleep";
 import { extractDomain } from "@/utils/extractDomain";
 import { ConfigType } from "@/types/evcc";
-import type { DeviceType } from "@/types/evcc";
+import type { DeviceType, Timeout } from "@/types/evcc";
 import {
 	handleError,
 	type DeviceValues,
@@ -172,6 +175,7 @@ import {
 	type ApiData,
 	applyDefaultsFromTemplate,
 	createDeviceUtils,
+	fetchServiceValues,
 } from "./index";
 
 const CUSTOM_FIELDS = ["modbus"];
@@ -248,6 +252,8 @@ export default defineComponent({
 			loadingTemplate: false,
 			values: { ...this.initialValues } as DeviceValues,
 			test: initialTestState(),
+			serviceValues: {} as Record<string, string[]>,
+			serviceValuesTimer: null as Timeout | null,
 		};
 	},
 	computed: {
@@ -423,6 +429,8 @@ export default defineComponent({
 			if (!isYamlInput) {
 				this.loadTemplate();
 			}
+
+			this.updateServiceValues();
 		},
 		usage() {
 			// Reload products when usage changes (e.g., meter type selection)
@@ -446,9 +454,22 @@ export default defineComponent({
 		values: {
 			handler() {
 				this.test = initialTestState();
+				this.updateServiceValues();
 			},
 			deep: true,
 		},
+		authValues: {
+			handler() {
+				if (this.authRequired) {
+					this.resetAuthStatus();
+				}
+			},
+			deep: true,
+		},
+		authRequired() {
+			// update on auth state change
+			this.updateServiceValues();
+		},
 	},
 	methods: {
 		reset() {
@@ -515,9 +536,12 @@ export default defineComponent({
 			}
 			this.loadingTemplate = false;
 		},
-		async checkAuthStatus() {
+		resetAuthStatus() {
 			this.authOk = false;
 			this.authProviderUrl = null;
+		},
+		async checkAuthStatus() {
+			this.resetAuthStatus();
 
 			// no auth required
 			if (!this.template?.Auth) return;
@@ -532,8 +556,6 @@ export default defineComponent({
 			// validate data
 			if (this.authValuesMissing) return;
 
-			this.authOk = false;
-			this.authProviderUrl = null;
 			const { type } = this.template.Auth;
 			const values = this.authValues;
 			this.authLoading = true;
@@ -672,6 +694,14 @@ export default defineComponent({
 			}
 			return value === ConfigType.Custom;
 		},
+		async updateServiceValues() {
+			if (this.serviceValuesTimer) {
+				clearTimeout(this.serviceValuesTimer);
+			}
+			this.serviceValuesTimer = setTimeout(async () => {
+				this.serviceValues = await fetchServiceValues(this.templateParams, this.values);
+			}, 500);
+		},
 	},
 });
 </script>
diff --git a/assets/js/components/Config/DeviceModal/index.test.ts b/assets/js/components/Config/DeviceModal/index.test.ts
new file mode 100644
index 000000000..be912c419
--- /dev/null
+++ b/assets/js/components/Config/DeviceModal/index.test.ts
@@ -0,0 +1,54 @@
+import { describe, expect, it } from "vitest";
+import { createServiceEndpoints, type TemplateParam } from "./index";
+
+const buildParam = (name: string, service?: string): TemplateParam => ({
+  Name: name,
+  Required: false,
+  Advanced: false,
+  Deprecated: false,
+  Service: service,
+});
+
+describe("createServiceEndpoints", () => {
+  it("skips params without service", () => {
+    const params = [buildParam("home", "homes"), buildParam("power", "homes/{home}/sensors")];
+    const endpoints = createServiceEndpoints(params);
+    expect(endpoints.map((endpoint) => endpoint.name)).toEqual(["home", "power"]);
+  });
+
+  it("replaces single placeholder", () => {
+    const params = [buildParam("home", "homes"), buildParam("power", "homes/{home}/sensors")];
+    const endpoints = createServiceEndpoints(params);
+    const homeEndpoint = endpoints.find(({ name }) => name === "home")!;
+    const powerEndpoint = endpoints.find(({ name }) => name === "power")!;
+    expect(homeEndpoint.dependencies).toEqual([]);
+    expect(homeEndpoint.url({})).toBe("homes");
+    expect(powerEndpoint.dependencies).toEqual(["home"]);
+    expect(powerEndpoint.url({ home: "main" })).toBe("homes/main/sensors");
+    expect(powerEndpoint.url({ home: "with space" })).toBe("homes/with%20space/sensors");
+    expect(powerEndpoint.url({} as Record<string, string>)).toBe("homes/{home}/sensors");
+  });
+
+  it("replaces multiple placeholders", () => {
+    const params = [
+      buildParam("home", "homes"),
+      buildParam("sensor", "homes/{home}/sensors/{sensor}"),
+    ];
+    const endpoints = createServiceEndpoints(params);
+    const sensorEndpoint = endpoints.find(({ name }) => name === "sensor")!;
+    expect(sensorEndpoint.dependencies).toEqual(["home", "sensor"]);
+    expect(sensorEndpoint.url({ home: "hq", sensor: "battery" })).toBe("homes/hq/sensors/battery");
+  });
+
+  it("encodes replacements", () => {
+    const params = [buildParam("token", "homes/{home}/sensors/{sensor}?token={token}")];
+    const endpoints = createServiceEndpoints(params);
+    const tokenEndpoint = endpoints[0]!;
+    expect(tokenEndpoint.url({ home: "hq", sensor: "bat/tery", token: "a+b c" })).toBe(
+      "homes/hq/sensors/bat%2Ftery?token=a%2Bb%20c"
+    );
+    expect(tokenEndpoint.url({} as Record<string, string>)).toBe(
+      "homes/{home}/sensors/{sensor}?token={token}"
+    );
+  });
+});
diff --git a/assets/js/components/Config/DeviceModal/index.ts b/assets/js/components/Config/DeviceModal/index.ts
index bff814364..58d62b7b4 100644
--- a/assets/js/components/Config/DeviceModal/index.ts
+++ b/assets/js/components/Config/DeviceModal/index.ts
@@ -1,6 +1,7 @@
 import type { DeviceType, MODBUS_COMSET, MeterTemplateUsage } from "@/types/evcc";
 import { ConfigType } from "@/types/evcc";
 import api, { baseApi } from "@/api";
+import { extractPlaceholders, replacePlaceholders } from "@/utils/placeholder";
 
 export type Product = {
   group: string;
@@ -28,9 +29,16 @@ export type TemplateParam = {
   Deprecated: boolean;
   Default?: string | number | boolean;
   Choice?: string[];
+  Service?: string;
   Usages?: TemplateParamUsage[];
 };
 
+export type ParamService = {
+  name: string;
+  dependencies: string[];
+  url: (values: Record<string, any>) => string;
+};
+
 export type ModbusCapability = "rs485" | "tcpip";
 
 export type ModbusParam = TemplateParam & {
@@ -106,6 +114,68 @@ export function customChargerName(type: ConfigType, isHeating: boolean) {
   return `${prefix}${type}`;
 }
 
+export async function loadServiceValues(path: string) {
+  try {
+    const response = await api.get(`/config/service/${path}`);
+    return response.data as string[];
+  } catch (e) {
+    console.error(e);
+    return [];
+  }
+}
+
+export const createServiceEndpoints = (params: TemplateParam[]): ParamService[] => {
+  return params
+    .map((param) => {
+      if (!param.Service) {
+        return null;
+      }
+      const stringValues = (values: Record<string, any>): Record<string, string> =>
+        Object.entries(values).reduce(
+          (acc, [key, val]) => {
+            if (val !== undefined && val !== null) acc[key] = String(val);
+            return acc;
+          },
+          {} as Record<string, string>
+        );
+
+      return {
+        name: param.Name,
+        dependencies: extractPlaceholders(param.Service),
+        url: (values: Record<string, any>) =>
+          replacePlaceholders(param.Service!, stringValues(values)),
+      } as ParamService;
+    })
+    .filter((endpoint): endpoint is ParamService => endpoint !== null);
+};
+
+export const fetchServiceValues = async (
+  templateParams: TemplateParam[],
+  values: DeviceValues
+): Promise<Record<string, string[]>> => {
+  const endpoints = createServiceEndpoints(templateParams);
+  const result: Record<string, string[]> = {};
+
+  await Promise.all(
+    endpoints.map(async (endpoint) => {
+      const params: Record<string, any> = {};
+      endpoint.dependencies.forEach((dependency) => {
+        if (values[dependency]) {
+          params[dependency] = values[dependency];
+        }
+      });
+      if (Object.keys(params).length !== endpoint.dependencies.length) {
+        // missing dependency values, skip
+        return;
+      }
+      const url = endpoint.url(params);
+      result[endpoint.name] = await loadServiceValues(url);
+    })
+  );
+
+  return result;
+};
+
 export function createDeviceUtils(deviceType: DeviceType) {
   function test(id: number | undefined, data: any) {
     let url = `config/test/${deviceType}`;
@@ -201,6 +271,7 @@ export function createDeviceUtils(deviceType: DeviceType) {
     create,
     loadProducts,
     loadTemplate,
+    loadServiceValues,
     checkAuth,
     getAuthProviderUrl,
   };
diff --git a/assets/js/components/Config/PropertyEntry.vue b/assets/js/components/Config/PropertyEntry.vue
index bda67ae43..b209bb7a4 100644
--- a/assets/js/components/Config/PropertyEntry.vue
+++ b/assets/js/components/Config/PropertyEntry.vue
@@ -17,6 +17,7 @@
 			:unit="Unit"
 			:required="Required"
 			:choice="Choice"
+			:service-values="serviceValues"
 			:label="label"
 		/>
 	</FormRow>
@@ -42,6 +43,7 @@ export default {
 		Unit: String,
 		Mask: Boolean,
 		Choice: Array,
+		serviceValues: Array,
 		modelValue: [String, Number, Boolean, Object],
 	},
 	emits: ["update:modelValue"],
diff --git a/assets/js/components/Config/PropertyField.vue b/assets/js/components/Config/PropertyField.vue
index a26dfe3ca..69af59582 100644
--- a/assets/js/components/Config/PropertyField.vue
+++ b/assets/js/components/Config/PropertyField.vue
@@ -77,18 +77,27 @@
 		:required="required"
 		rows="4"
 	/>
-	<input
-		v-else
-		:id="id"
-		v-model="value"
-		class="form-control"
-		:class="inputClasses"
-		:type="inputType"
-		:step="step"
-		:placeholder="placeholder"
-		:required="required"
-		:autocomplete="masked ? 'off' : null"
-	/>
+	<div v-else class="position-relative">
+		<input
+			:id="id"
+			v-model="value"
+			:list="datalistId"
+			:class="`${datalistId && serviceValues.length > 0 ? 'form-select' : 'form-control'} ${inputClasses}`"
+			:type="inputType"
+			:step="step"
+			:placeholder="placeholder"
+			:required="required"
+			:autocomplete="masked || datalistId ? 'off' : null"
+		/>
+		<button v-if="showClearButton" type="button" class="form-control-clear" @click="value = ''">
+			&times;
+		</button>
+		<datalist v-if="showDatalist" :id="datalistId">
+			<option v-for="v in serviceValues" :key="v" :value="v">
+				{{ v }}
+			</option>
+		</datalist>
+	</div>
 </template>
 
 <script>
@@ -117,12 +126,28 @@ export default {
 		choice: { type: Array, default: () => [] },
 		modelValue: [String, Number, Boolean, Object],
 		label: String,
+		serviceValues: { type: Array, default: () => [] },
 	},
 	emits: ["update:modelValue"],
 	data: () => {
 		return { selectMode: false };
 	},
 	computed: {
+		datalistId() {
+			return this.serviceValues.length > 0 ? `${this.id}-datalist` : null;
+		},
+		showDatalist() {
+			if (!this.datalistId) return false;
+			const length = this.serviceValues.length;
+			// no values
+			if (length === 0) return false;
+			// value selected, dont offer single same option again
+			if (this.value && this.serviceValues.includes(this.value)) return false;
+			return true;
+		},
+		showClearButton() {
+			return this.datalistId && this.value;
+		},
 		inputType() {
 			if (this.masked) {
 				return "password";
@@ -146,6 +171,9 @@ export default {
 			if (this.invalid) {
 				result += " is-invalid";
 			}
+			if (this.showClearButton) {
+				result += " has-clear-button";
+			}
 			return result;
 		},
 		endAlign() {
diff --git a/assets/js/utils/placeholder.test.ts b/assets/js/utils/placeholder.test.ts
new file mode 100644
index 000000000..c0b2bda44
--- /dev/null
+++ b/assets/js/utils/placeholder.test.ts
@@ -0,0 +1,26 @@
+import { describe, it, expect } from "vitest";
+import { extractPlaceholders as extract, replacePlaceholders as replace } from "./placeholder";
+
+describe("placeholder", () => {
+  it("extract", () => {
+    expect(extract("homes")).toEqual([]);
+    expect(extract("")).toEqual([]);
+    expect(extract("a/{home}/b")).toEqual(["home"]);
+    expect(extract("{a}/{b}")).toEqual(["a", "b"]);
+    expect(extract("{p1}/{p2}")).toEqual(["p1", "p2"]);
+    expect(extract("{a_b}/{c_d}")).toEqual(["a_b", "c_d"]);
+    expect(extract("{a}/{a}")).toEqual(["a", "a"]);
+  });
+
+  it("replace", () => {
+    expect(replace("homes", {})).toBe("homes");
+    expect(replace("a/{b}/c", { b: "x" })).toBe("a/x/c");
+    expect(replace("{a}/{b}", { a: "1", b: "2" })).toBe("1/2");
+    expect(replace("{a}", { a: "b c" })).toBe("b%20c");
+    expect(replace("{a}", { a: "b/c" })).toBe("b%2Fc");
+    expect(replace("{a}", { a: "b+c" })).toBe("b%2Bc");
+    expect(replace("{a}", {})).toBe("{a}");
+    expect(replace("{a}", { a: "" })).toBe("");
+    expect(replace("{a}/{b}", { a: "x" })).toBe("x/{b}");
+  });
+});
diff --git a/assets/js/utils/placeholder.ts b/assets/js/utils/placeholder.ts
new file mode 100644
index 000000000..6656e47c5
--- /dev/null
+++ b/assets/js/utils/placeholder.ts
@@ -0,0 +1,20 @@
+/** Matches {placeholder} names (letters, numbers, underscores) */
+const PLACEHOLDER_PATTERN = /\{(\w+)\}/g;
+
+/** Extract {placeholder} names from template */
+export function extractPlaceholders(template: string): string[] {
+  const matches = template.match(PLACEHOLDER_PATTERN);
+  if (!matches) return [];
+  return matches.map((match) => match.slice(1, -1));
+}
+
+/** Replace {placeholders} with URL-encoded values */
+export function replacePlaceholders(template: string, values: Record<string, string>): string {
+  return template.replace(PLACEHOLDER_PATTERN, (match, key) => {
+    const value = values[key];
+    if (value === undefined) {
+      return match;
+    }
+    return encodeURIComponent(value);
+  });
+}
diff --git a/charger/homeassistant-switch.go b/charger/homeassistant-switch.go
index 9bf52f6cc..3dc1917c8 100644
--- a/charger/homeassistant-switch.go
+++ b/charger/homeassistant-switch.go
@@ -20,23 +20,26 @@ func init() {
 }
 
 func NewHomeAssistantSwitchFromConfig(other map[string]any) (api.Charger, error) {
-	var cc struct {
+	cc := struct {
 		embed        `mapstructure:",squash"`
-		URI          string
-		Token        string
+		_URI         string `mapstructure:"uri"`   // TODO deprecated
+		_Token       string `mapstructure:"token"` // TODO deprecated
+		Home         string
 		Enable       string
 		Power        string
 		StandbyPower float64
+	}{
+		Home: "Home",
 	}
 
 	if err := util.DecodeOther(other, &cc); err != nil {
 		return nil, err
 	}
 
-	return NewHomeAssistantSwitch(cc.embed, cc.URI, cc.Token, cc.Enable, cc.Power, cc.StandbyPower)
+	return NewHomeAssistantSwitch(cc.embed, cc.Home, cc.Enable, cc.Power, cc.StandbyPower)
 }
 
-func NewHomeAssistantSwitch(embed embed, uri, token, enable, power string, standbypower float64) (api.Charger, error) {
+func NewHomeAssistantSwitch(embed embed, home, enable, power string, standbypower float64) (api.Charger, error) {
 	if enable == "" {
 		return nil, errors.New("missing enable switch entity")
 	}
@@ -47,7 +50,7 @@ func NewHomeAssistantSwitch(embed embed, uri, token, enable, power string, stand
 	}
 
 	log := util.NewLogger("ha-switch")
-	conn, err := homeassistant.NewConnection(log, uri, token)
+	conn, err := homeassistant.NewConnection(log, home)
 	if err != nil {
 		return nil, err
 	}
diff --git a/charger/homeassistant.go b/charger/homeassistant.go
index b75f4f2aa..6811cb3d8 100644
--- a/charger/homeassistant.go
+++ b/charger/homeassistant.go
@@ -28,8 +28,9 @@ func init() {
 // NewHomeAssistantFromConfig creates a HomeAssistant charger from generic config
 func NewHomeAssistantFromConfig(other map[string]any) (api.Charger, error) {
 	cc := struct {
-		URI        string
-		Token      string
+		_URI       string `mapstructure:"uri"`   // TODO deprecated
+		_Token     string `mapstructure:"token"` // TODO deprecated
+		Home       string
 		Status     string   // required - sensor for charge status
 		Enabled    string   // required - sensor for enabled state
 		Enable     string   // required - switch/input_boolean for enable/disable
@@ -38,7 +39,9 @@ func NewHomeAssistantFromConfig(other map[string]any) (api.Charger, error) {
 		Energy     string   // optional - energy sensor
 		Currents   []string // optional - current sensors for L1, L2, L3
 		Voltages   []string // optional - voltage sensors for L1, L2, L3
-	}{}
+	}{
+		Home: "Home",
+	}
 
 	if err := util.DecodeOther(other, &cc); err != nil {
 		return nil, err
@@ -55,7 +58,7 @@ func NewHomeAssistantFromConfig(other map[string]any) (api.Charger, error) {
 	}
 
 	log := util.NewLogger("ha-charger")
-	conn, err := homeassistant.NewConnection(log, cc.URI, cc.Token)
+	conn, err := homeassistant.NewConnection(log, cc.Home)
 	if err != nil {
 		return nil, err
 	}
diff --git a/cmd/root.go b/cmd/root.go
index e1564e288..2366273f4 100644
--- a/cmd/root.go
+++ b/cmd/root.go
@@ -18,6 +18,7 @@ import (
 	"github.com/evcc-io/evcc/server"
 	"github.com/evcc-io/evcc/server/db"
 	"github.com/evcc-io/evcc/server/mcp"
+	"github.com/evcc-io/evcc/server/network"
 	"github.com/evcc-io/evcc/server/updater"
 	"github.com/evcc-io/evcc/util"
 	"github.com/evcc-io/evcc/util/auth"
@@ -157,6 +158,12 @@ func runRoot(cmd *cobra.Command, args []string) {
 		err = networkSettings(&conf.Network)
 	}
 
+	// configure plugin external url
+	if err == nil {
+		// network configuration complete, start dependent services like HomeAssistant discovery
+		network.Start(conf.Network)
+	}
+
 	// start broadcasting values
 	tee := new(util.Tee)
 	valueChan := make(chan util.Param, 64)
diff --git a/meter/homeassistant.go b/meter/homeassistant.go
index 889a49219..499a9b755 100644
--- a/meter/homeassistant.go
+++ b/meter/homeassistant.go
@@ -24,8 +24,9 @@ func init() {
 // NewHomeAssistantFromConfig creates a HomeAssistant meter from generic config
 func NewHomeAssistantFromConfig(other map[string]any) (api.Meter, error) {
 	cc := struct {
-		URI      string
-		Token    string
+		_URI     string `mapstructure:"uri"`   // TODO deprecated
+		_Token   string `mapstructure:"token"` // TODO deprecated
+		Home     string
 		Power    string
 		Energy   string
 		Currents []string
@@ -40,6 +41,7 @@ func NewHomeAssistantFromConfig(other map[string]any) (api.Meter, error) {
 		batterySocLimits   `mapstructure:",squash"`
 		batteryPowerLimits `mapstructure:",squash"`
 	}{
+		Home: "Home",
 		batterySocLimits: batterySocLimits{
 			MinSoc: 20,
 			MaxSoc: 95,
@@ -55,7 +57,7 @@ func NewHomeAssistantFromConfig(other map[string]any) (api.Meter, error) {
 	}
 
 	log := util.NewLogger("ha-meter")
-	conn, err := homeassistant.NewConnection(log, cc.URI, cc.Token)
+	conn, err := homeassistant.NewConnection(log, cc.Home)
 	if err != nil {
 		return nil, err
 	}
diff --git a/package-lock.json b/package-lock.json
index d82898c2f..33b7a2d9e 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -12,7 +12,7 @@
         "@h2d2/shopicons": "^1.9.0",
         "@popperjs/core": "^2.11.8",
         "@unhead/vue": "^2.0.14",
-        "axios": "^1.12.0",
+        "axios": "^1.13.2",
         "bootstrap": "^5.3.8",
         "canvas-confetti": "^1.9.3",
         "chart.js": "^4.5.0",
diff --git a/package.json b/package.json
index a365d2d39..1b781fcca 100644
--- a/package.json
+++ b/package.json
@@ -24,7 +24,7 @@
     "@h2d2/shopicons": "^1.9.0",
     "@popperjs/core": "^2.11.8",
     "@unhead/vue": "^2.0.14",
-    "axios": "^1.12.0",
+    "axios": "^1.13.2",
     "bootstrap": "^5.3.8",
     "canvas-confetti": "^1.9.3",
     "chart.js": "^4.5.0",
diff --git a/push/hub.go b/push/hub.go
index ba760edb9..2a3e96f0e 100644
--- a/push/hub.go
+++ b/push/hub.go
@@ -7,6 +7,7 @@ import (
 	"text/template"
 
 	"github.com/Masterminds/sprig/v3"
+	"github.com/evcc-io/evcc/api/globalconfig"
 	"github.com/evcc-io/evcc/core/vehicle"
 	"github.com/evcc-io/evcc/util"
 )
@@ -17,11 +18,6 @@ type Event struct {
 	Event     string
 }
 
-// EventTemplateConfig is the push message configuration for an event
-type EventTemplateConfig struct {
-	Title, Msg string
-}
-
 type Vehicles interface {
 	// ByName returns a single vehicle adapter by name
 	ByName(string) (vehicle.API, error)
@@ -29,14 +25,14 @@ type Vehicles interface {
 
 // Hub subscribes to event notifications and sends them to client devices
 type Hub struct {
-	definitions map[string]EventTemplateConfig
+	definitions map[string]globalconfig.MessagingEventTemplate
 	sender      []Messenger
 	cache       *util.ParamCache
 	vehicles    Vehicles
 }
 
 // NewHub creates push hub with definitions and receiver
-func NewHub(cc map[string]EventTemplateConfig, vv Vehicles, cache *util.ParamCache) (*Hub, error) {
+func NewHub(cc map[string]globalconfig.MessagingEventTemplate, vv Vehicles, cache *util.ParamCache) (*Hub, error) {
 	// instantiate all event templates
 	for k, v := range cc {
 		if _, err := template.New("out").Funcs(sprig.FuncMap()).Parse(v.Title); err != nil {
diff --git a/server/http.go b/server/http.go
index a6a8f769a..82375b05d 100644
--- a/server/http.go
+++ b/server/http.go
@@ -15,6 +15,7 @@ import (
 	"github.com/evcc-io/evcc/hems/shm"
 	"github.com/evcc-io/evcc/server/assets"
 	"github.com/evcc-io/evcc/server/eebus"
+	"github.com/evcc-io/evcc/server/service"
 	"github.com/evcc-io/evcc/util"
 	"github.com/evcc-io/evcc/util/auth"
 	"github.com/evcc-io/evcc/util/config"
@@ -321,6 +322,9 @@ func (s *HTTPd) RegisterSystemHandler(site *core.Site, valueChan chan<- util.Par
 			api.Methods(r.Methods()...).Path(r.Pattern).Handler(r.HandlerFunc)
 		}
 
+		// services
+		api.PathPrefix("/service").Handler(http.StripPrefix("/api/config/service", service.Handler()))
+
 		// site
 		for _, r := range map[string]route{
 			"site":       {"GET", "/site", siteHandler(site)},
diff --git a/server/network/registry.go b/server/network/registry.go
new file mode 100644
index 000000000..b3bd0a23d
--- /dev/null
+++ b/server/network/registry.go
@@ -0,0 +1,33 @@
+package network
+
+import (
+	"sync"
+
+	"github.com/evcc-io/evcc/api/globalconfig"
+)
+
+var (
+	mu       sync.Mutex
+	registry []func()
+)
+
+var config globalconfig.Network
+
+func Config() globalconfig.Network {
+	return config
+}
+
+func Register(fun func()) {
+	mu.Lock()
+	defer mu.Unlock()
+
+	registry = append(registry, fun)
+}
+
+func Start(conf globalconfig.Network) {
+	config = conf
+
+	for _, fun := range registry {
+		go fun()
+	}
+}
diff --git a/server/service/registry.go b/server/service/registry.go
new file mode 100644
index 000000000..6997da72c
--- /dev/null
+++ b/server/service/registry.go
@@ -0,0 +1,36 @@
+package service
+
+import (
+	"net/http"
+	"sync"
+)
+
+var (
+	mu       sync.Mutex
+	registry = make(map[string]http.Handler)
+)
+
+func Register(name string, handler http.Handler) {
+	mu.Lock()
+	defer mu.Unlock()
+
+	if _, ok := registry[name]; ok {
+		panic("service " + name + " already registered")
+	}
+
+	registry[name] = handler
+}
+
+func Handler() http.Handler {
+	mux := http.NewServeMux()
+
+	for name, h := range registry {
+		// e.g. "/homes/foo"
+		prefix := "/" + name
+
+		// strip "/homes/foo" then hand off to h
+		mux.Handle(prefix+"/", http.StripPrefix(prefix, h))
+	}
+
+	return mux
+}
diff --git a/templates/definition/charger/homeassistant-switch.yaml b/templates/definition/charger/homeassistant-switch.yaml
index bd028cee2..88de1cc4e 100644
--- a/templates/definition/charger/homeassistant-switch.yaml
+++ b/templates/definition/charger/homeassistant-switch.yaml
@@ -7,35 +7,37 @@ products:
 group: switchsockets
 requirements:
   evcc: ["skiptest"]
+auth:
+  type: homeassistant
+  params: [home]
 params:
   - name: uri
-    required: true
-    example: http://homeassistant.local:8123
+    deprecated: true
   - name: token
-    mask: true
-    required: true
+    deprecated: true
+  - name: home
     description:
-      de: Long-Lived Access Token
-      en: Long-Lived Access Token
-    help:
-      de: aus Home Assistant Profil
-      en: from Home Assistant profile
+      de: Home Assistant Instanz
+      en: Home Assistant Instance
+    default: Home
+    service: homeassistant/homes
   - name: switch
-    required: true
     description:
       de: Entity ID des schaltbaren Geräts
       en: Entity ID of the switch device
+    service: homeassistant/homes/{home}/entities?domain=switch
     example: switch.smartsocket
+    required: true
   - name: power
     description:
       de: Entity ID für Leistungsmessung
       en: Entity ID for power measurement
+    service: homeassistant/homes/{home}/entities?domain=sensor
     example: sensor.smartsocket_power
   - preset: switchsocket
 render: |
   type: homeassistant-switch
-  uri: {{ .uri }}
-  token: {{ .token }}
+  home: {{ .home }}
   enable: {{ .switch }}
   power: {{ .power }}
   {{ include "switchsocket" . }}
diff --git a/templates/definition/meter/homeassistant.yaml b/templates/definition/meter/homeassistant.yaml
index 2d0baaf91..11260c980 100644
--- a/templates/definition/meter/homeassistant.yaml
+++ b/templates/definition/meter/homeassistant.yaml
@@ -7,26 +7,31 @@ products:
 group: generic
 requirements:
   description:
-    en: Home Assistant instance with API access
-    de: Home Assistant Instanz mit API-Zugriff
+    en: Requires a running Home Assistant instance with suitable sensor entities. All values are Home Assistant entity IDs (e.g. sensor.*)
+    de: Erfordert eine laufende Home Assistant Instanz mit passenden Sensor-Entitäten. Alle Werte sind Home Assistant Entity IDs (z.B. sensor.*)
+auth:
+  type: homeassistant
+  params: [home]
 params:
   - name: usage
     choice: ["grid", "pv", "battery", "aux", "charge"]
   - name: uri
-    required: true
-    example: "http://homeassistant.local:8123"
+    deprecated: true
   - name: token
+    deprecated: true
+  - name: home
     description:
-      de: Home Assistant Long-Lived Access Token
-      en: Home Assistant Long-Lived Access Token
-    example: "eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9..."
+      de: Home Assistant Instanz
+      en: Home Assistant Instance
+    default: Home
+    service: homeassistant/homes
     required: true
-    mask: true
   - name: power
     description:
       de: Leistungsentität
       en: Power Entity
     required: true
+    service: homeassistant/homes/{home}/entities?domain=sensor
     example: "sensor.house_power"
     help:
       en: Entity ID for instantaneous power measurement in watts. The entity must provide numeric values only (e.g., "1234", not "1234 W").
@@ -35,6 +40,7 @@ params:
     description:
       de: Energieentität
       en: Energy Entity
+    service: homeassistant/homes/{home}/entities?domain=sensor
     example: "sensor.house_energy"
     advanced: true
     help:
@@ -44,6 +50,7 @@ params:
     description:
       de: L1 Stromentität
       en: L1 Current Entity
+    service: homeassistant/homes/{home}/entities?domain=sensor
     example: "sensor.house_current_l1"
     advanced: true
     help:
@@ -53,6 +60,7 @@ params:
     description:
       de: L2 Stromentität
       en: L2 Current Entity
+    service: homeassistant/homes/{home}/entities?domain=sensor
     example: "sensor.house_current_l2"
     advanced: true
     help:
@@ -62,6 +70,7 @@ params:
     description:
       de: L3 Stromentität
       en: L3 Current Entity
+    service: homeassistant/homes/{home}/entities?domain=sensor
     example: "sensor.house_current_l3"
     advanced: true
     help:
@@ -71,6 +80,7 @@ params:
     description:
       de: L1 Spannungsentität
       en: L1 Voltage Entity
+    service: homeassistant/homes/{home}/entities?domain=sensor
     example: "sensor.house_voltage_l1"
     advanced: true
     help:
@@ -80,6 +90,7 @@ params:
     description:
       de: L2 Spannungsentität
       en: L2 Voltage Entity
+    service: homeassistant/homes/{home}/entities?domain=sensor
     example: "sensor.house_voltage_l2"
     advanced: true
     help:
@@ -89,6 +100,7 @@ params:
     description:
       de: L3 Spannungsentität
       en: L3 Voltage Entity
+    service: homeassistant/homes/{home}/entities?domain=sensor
     example: "sensor.house_voltage_l3"
     advanced: true
     help:
@@ -98,6 +110,7 @@ params:
     description:
       de: Batterieladestand
       en: Battery State of Charge
+    service: homeassistant/homes/{home}/entities?domain=sensor
     example: "sensor.battery_soc"
     advanced: true
     help:
@@ -111,8 +124,7 @@ params:
   - name: maxacpower
 render: |
   type: homeassistant
-  uri: {{ .uri }}
-  token: {{ .token }}
+  home: {{ .home }}
   power: {{ .power }}
   energy: {{ .energy }}
   currents:
diff --git a/templates/definition/vehicle/homeassistant.yaml b/templates/definition/vehicle/homeassistant.yaml
index d324b3bd8..92332e6a9 100644
--- a/templates/definition/vehicle/homeassistant.yaml
+++ b/templates/definition/vehicle/homeassistant.yaml
@@ -9,85 +9,89 @@ requirements:
   description:
     en: Requires a running Home Assistant instance with suitable vehicle entities and services. All values are Home Assistant entity IDs (e.g. sensor.*, binary_sensor.*, number.*, script.*)
     de: Erfordert eine laufende Home Assistant Instanz mit passenden Fahrzeug-Entities und Services. Alle Werte sind Home Assistant Entity IDs (z.B. sensor.*, binary_sensor.*, number.*, script.*)
+auth:
+  type: homeassistant
+  params: [home]
 params:
   - preset: vehicle-common
   - name: uri
-    required: true
-    example: http://homeassistant.local:8123
+    deprecated: true
   - name: token
+    deprecated: true
+  - name: home
     description:
-      de: Home Assistant Long-Lived Access Token
-      en: Home Assistant Long-Lived Access Token
-    example: "eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9..."
+      de: Home Assistant Instanz
+      en: Home Assistant Instance
+    default: Home
+    service: homeassistant/homes
     required: true
-    mask: true
   - name: soc
     description:
       de: Ladezustand [%]
       en: State of charge [%]
+    service: homeassistant/homes/{home}/entities?domain=sensor
     example: "sensor.vehicle_soc"
-    type: string
     required: true
   - name: range
     description:
       de: Restreichweite [km]
       en: Remaining range [km]
+    service: homeassistant/homes/{home}/entities?domain=sensor
     example: "sensor.vehicle_range"
-    type: string
   - name: status
     description:
       de: Ladestatus
       en: Charging status
+    service: homeassistant/homes/{home}/entities?domain=sensor
     example: "sensor.vehicle_charging"
-    type: string
   - name: limitSoc
     description:
       de: Ziel-Ladezustand [%]
       en: Target state of charge [%]
+    service: homeassistant/homes/{home}/entities?domain=number,input_number
     example: "number.vehicle_target_state_of_charge"
-    type: string
   - name: odometer
     description:
       de: Kilometerstand [km]
       en: Odometer [km]
+    service: homeassistant/homes/{home}/entities?domain=sensor
     example: "sensor.vehicle_odometer"
-    type: string
   - name: climater
     description:
       de: Klimatisierung aktiv
       en: Climatisation active
+    service: homeassistant/homes/{home}/entities?domain=binary_sensor
     example: "binary_sensor.vehicle_climater"
-    type: string
   - name: finishTime
     description:
       de: Ladeende (ISO8601 oder Unix)
       en: Finish time (ISO8601 or Unix)
+    service: homeassistant/homes/{home}/entities?domain=sensor
     example: "sensor.vehicle_finish_time"
-    type: string
   - name: start_charging
     description:
       de: Service zum Laden starten
       en: Service to start charging
+    service: homeassistant/homes/{home}/entities?domain=script
     example: "script.vehicle_start_charge"
-    type: string
   - name: stop_charging
     description:
       de: Service zum Laden stoppen
       en: Service to stop charging
+    service: homeassistant/homes/{home}/entities?domain=script
     example: "script.vehicle_stop_charge"
-    type: string
   - name: wakeup
     description:
       de: Service zum Aufwecken
       en: Service to wake up vehicle
+    service: homeassistant/homes/{home}/entities?domain=script
     example: "script.vehicle_wakeup"
-    type: string
   - name: setMaxCurrent
     description:
       de: Ladestromstärke setzen [A]
       en: Set charging current [A]
+    service: homeassistant/homes/{home}/entities?domain=number,input_number
     example: "number.vehicle_charging_current"
-    type: string
   - preset: vehicle-features
   - name: streaming
     default: true
@@ -95,8 +99,7 @@ render: |
   type: homeassistant
   {{ include "vehicle-common" . }}
   {{ include "vehicle-features" . }}
-  uri: {{ .uri }}
-  token: {{ .token }}
+  home: {{ .home }}
   sensors:
     soc: {{ .soc }}
     range: {{ .range }}
diff --git a/util/homeassistant/connection.go b/util/homeassistant/connection.go
index 2b6c509b6..a5a2304d7 100644
--- a/util/homeassistant/connection.go
+++ b/util/homeassistant/connection.go
@@ -11,52 +11,46 @@ import (
 	"github.com/evcc-io/evcc/api"
 	"github.com/evcc-io/evcc/util"
 	"github.com/evcc-io/evcc/util/request"
-	"github.com/evcc-io/evcc/util/transport"
 	"github.com/samber/lo"
+	"golang.org/x/oauth2"
 )
 
 // Connection represents a Home Assistant API connection
 type Connection struct {
 	*request.Helper
-	uri string
+	instance *proxyInstance
 }
 
 // NewConnection creates a new Home Assistant connection
-func NewConnection(log *util.Logger, uri, token string) (*Connection, error) {
-	if uri == "" {
-		return nil, errors.New("missing uri")
-	}
-	if token == "" {
-		return nil, errors.New("missing token")
-	}
-
+func NewConnection(log *util.Logger, home string) (*Connection, error) {
 	c := &Connection{
-		Helper: request.NewHelper(log.Redact(token)),
-		uri:    util.DefaultScheme(strings.TrimSuffix(uri, "/"), "http"),
+		Helper:   request.NewHelper(log),
+		instance: &proxyInstance{home: home},
 	}
 
 	// Set up authentication headers
-	c.Client.Transport = &transport.Decorator{
-		Base: c.Client.Transport,
-		Decorator: transport.DecorateHeaders(map[string]string{
-			"Authorization": "Bearer " + token,
-			"Content-Type":  "application/json",
-		}),
+	c.Client.Transport = &oauth2.Transport{
+		Base:   c.Client.Transport,
+		Source: c.instance,
 	}
 
 	return c, nil
 }
 
-// StateResponse represents a Home Assistant entity state
-type StateResponse struct {
-	State      string         `json:"state"`
-	Attributes map[string]any `json:"attributes"`
+// GetStates retrieves the list of entities
+func (c *Connection) GetStates() ([]StateResponse, error) {
+	var res []StateResponse
+	uri := fmt.Sprintf("%s/api/states", c.instance.URI())
+
+	err := c.GetJSON(uri, &res)
+
+	return res, err
 }
 
 // GetState retrieves the state of an entity
 func (c *Connection) GetState(entity string) (string, error) {
 	var res StateResponse
-	uri := fmt.Sprintf("%s/api/states/%s", c.uri, url.PathEscape(entity))
+	uri := fmt.Sprintf("%s/api/states/%s", c.instance.URI(), url.PathEscape(entity))
 
 	if err := c.GetJSON(uri, &res); err != nil {
 		return "", err
@@ -169,7 +163,7 @@ func (c *Connection) GetChargeStatus(entity string) (api.ChargeStatus, error) {
 
 // CallService calls a Home Assistant service
 func (c *Connection) CallService(domain, service string, data map[string]any) error {
-	uri := fmt.Sprintf("%s/api/services/%s/%s", c.uri, domain, service)
+	uri := fmt.Sprintf("%s/api/services/%s/%s", c.instance.URI(), domain, service)
 
 	req, err := request.New(http.MethodPost, uri, request.MarshalJSON(data), request.JSONEncoding)
 	if err != nil {
diff --git a/util/homeassistant/instance.go b/util/homeassistant/instance.go
new file mode 100644
index 000000000..d741566b5
--- /dev/null
+++ b/util/homeassistant/instance.go
@@ -0,0 +1,23 @@
+package homeassistant
+
+import (
+	"sync"
+
+	"golang.org/x/oauth2"
+)
+
+type instance struct {
+	URI string
+	oauth2.TokenSource
+}
+
+var (
+	mu        sync.Mutex
+	instances = make(map[string]*instance)
+)
+
+func instanceByName(name string) *instance {
+	mu.Lock()
+	defer mu.Unlock()
+	return instances[name]
+}
diff --git a/util/homeassistant/oauth2.go b/util/homeassistant/oauth2.go
new file mode 100644
index 000000000..42a3cba4c
--- /dev/null
+++ b/util/homeassistant/oauth2.go
@@ -0,0 +1,54 @@
+package homeassistant
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/evcc-io/evcc/plugin/auth"
+	"github.com/evcc-io/evcc/server/network"
+	"github.com/evcc-io/evcc/util"
+	"github.com/evcc-io/evcc/util/request"
+	"golang.org/x/oauth2"
+)
+
+// https://developers.home-assistant.io/docs/auth_api
+
+func init() {
+	auth.Register("homeassistant", NewHomeAssistantFromConfig)
+}
+
+func NewHomeAssistantFromConfig(other map[string]any) (oauth2.TokenSource, error) {
+	var cc struct {
+		Home string
+	}
+
+	if err := util.DecodeOther(other, &cc); err != nil {
+		return nil, err
+	}
+
+	inst := instanceByName(cc.Home)
+	if inst == nil {
+		return nil, fmt.Errorf("unknown instance: %s", cc.Home)
+	}
+
+	return NewHomeAssistant(cc.Home, inst.URI)
+}
+
+func NewHomeAssistant(name, uri string) (oauth2.TokenSource, error) {
+	extUrl := network.Config().ExternalURL()
+	redirectUri := extUrl + "/providerauth/callback"
+
+	log := util.NewLogger("homeassistant")
+	ctx := context.WithValue(context.Background(), oauth2.HTTPClient, request.NewClient(log))
+
+	oc := oauth2.Config{
+		ClientID:    extUrl,
+		RedirectURL: redirectUri,
+		Endpoint: oauth2.Endpoint{
+			AuthURL:  uri + "/auth/authorize",
+			TokenURL: uri + "/auth/token",
+		},
+	}
+
+	return auth.NewOAuth(ctx, "HomeAssistant", name, &oc)
+}
diff --git a/util/homeassistant/proxy.go b/util/homeassistant/proxy.go
new file mode 100644
index 000000000..c2408b182
--- /dev/null
+++ b/util/homeassistant/proxy.go
@@ -0,0 +1,44 @@
+package homeassistant
+
+import (
+	"fmt"
+	"sync"
+
+	"golang.org/x/oauth2"
+)
+
+type proxyInstance struct {
+	mu       sync.Mutex
+	home     string
+	instance *instance
+}
+
+func (inst *proxyInstance) URI() string {
+	inst.mu.Lock()
+	defer inst.mu.Unlock()
+
+	if inst.instance == nil {
+		inst.instance = instanceByName(inst.home)
+
+		if inst.instance == nil {
+			return ""
+		}
+	}
+
+	return inst.instance.URI
+}
+
+func (inst *proxyInstance) Token() (*oauth2.Token, error) {
+	inst.mu.Lock()
+	defer inst.mu.Unlock()
+
+	if inst.instance == nil {
+		inst.instance = instanceByName(inst.home)
+
+		if inst.instance == nil {
+			return nil, fmt.Errorf("unknown instance: %s", inst.home)
+		}
+	}
+
+	return inst.instance.Token()
+}
diff --git a/util/homeassistant/service.go b/util/homeassistant/service.go
new file mode 100644
index 000000000..302662d2c
--- /dev/null
+++ b/util/homeassistant/service.go
@@ -0,0 +1,81 @@
+package homeassistant
+
+import (
+	"encoding/json"
+	"maps"
+	"net/http"
+	"slices"
+	"strings"
+
+	"github.com/evcc-io/evcc/server/service"
+	"github.com/evcc-io/evcc/util"
+	"github.com/samber/lo"
+)
+
+var log = util.NewLogger("homeassistant")
+
+func init() {
+	mux := http.NewServeMux()
+	mux.HandleFunc("GET /homes", getHomes)
+	mux.HandleFunc("GET /homes/{home}/entities", getEntities)
+
+	service.Register("homeassistant", mux)
+}
+
+func getHomes(w http.ResponseWriter, req *http.Request) {
+	mu.Lock()
+	defer mu.Unlock()
+
+	jsonWrite(w, slices.Sorted(maps.Keys(instances)))
+}
+
+func getEntities(w http.ResponseWriter, req *http.Request) {
+	home := req.PathValue("home")
+
+	if instanceByName(home) == nil {
+		w.WriteHeader(http.StatusBadRequest)
+		return
+	}
+
+	conn, _ := NewConnection(log, home)
+	res, err := conn.GetStates()
+	if err != nil {
+		jsonError(w, http.StatusBadRequest, err)
+		return
+	}
+
+	var domains []string
+	if domain := req.URL.Query().Get("domain"); domain != "" {
+		domains = strings.Split(domain, ",")
+	}
+
+	// cache list of entities
+	w.Header().Set("Cache-control", "max-age=300")
+
+	jsonWrite(w, lo.Map(lo.Filter(res, func(e StateResponse, _ int) bool {
+		if len(domains) == 0 {
+			return true
+		}
+
+		for _, domain := range domains {
+			if strings.HasPrefix(e.EntityId, domain+".") {
+				return true
+			}
+		}
+
+		return false
+	}), func(e StateResponse, _ int) string {
+		return e.EntityId
+	}))
+}
+
+// jsonWrite writes a JSON response
+func jsonWrite(w http.ResponseWriter, data any) {
+	json.NewEncoder(w).Encode(data)
+}
+
+// jsonError writes an error response
+func jsonError(w http.ResponseWriter, status int, err error) {
+	w.WriteHeader(status)
+	jsonWrite(w, util.ErrorAsJson(err))
+}
diff --git a/util/homeassistant/types.go b/util/homeassistant/types.go
new file mode 100644
index 000000000..f23311056
--- /dev/null
+++ b/util/homeassistant/types.go
@@ -0,0 +1,11 @@
+package homeassistant
+
+type StateResponse struct {
+	EntityId   string `json:"entity_id"`
+	State      string `json:"state"`
+	Attributes struct {
+		UnitOfMeasurement string `json:"unit_of_measurement"`
+		DeviceClass       string `json:"device_class"`
+		FriendlyName      string `json:"friendly_name"`
+	} `json:"attributes"`
+}
diff --git a/util/homeassistant/zeroconf.go b/util/homeassistant/zeroconf.go
new file mode 100644
index 000000000..1f6ad2ee1
--- /dev/null
+++ b/util/homeassistant/zeroconf.go
@@ -0,0 +1,73 @@
+package homeassistant
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"github.com/evcc-io/evcc/server/network"
+	"github.com/evcc-io/evcc/util"
+	"github.com/libp2p/zeroconf/v2"
+)
+
+func init() {
+	network.Register(scan)
+}
+
+func scan() {
+	ctx := context.Background()
+
+	log := util.NewLogger("homeassistant")
+	entries := make(chan *zeroconf.ServiceEntry, 1)
+
+	go func() {
+		for {
+			select {
+			case se := <-entries:
+				uri := fmt.Sprintf("http://%s:%d", se.HostName, se.Port)
+
+			OUTER:
+				for _, text := range se.Text {
+					for _, prefix := range []string{"external_url", "base_url", "internal_url"} {
+						if u, ok := strings.CutPrefix(text, prefix+"="); ok && u != "" {
+							uri = u
+							break OUTER
+						}
+					}
+				}
+
+				if err := authorize(se.Instance, uri); err != nil {
+					log.ERROR.Println(err)
+				}
+
+			case <-ctx.Done():
+				return
+			}
+		}
+	}()
+
+	if err := zeroconf.Browse(ctx, "_home-assistant._tcp.", "local.", entries); err != nil {
+		log.ERROR.Println("zeroconf: failed to browse:", err.Error())
+	}
+}
+
+func authorize(name, uri string) error {
+	mu.Lock()
+	defer mu.Unlock()
+
+	if _, ok := instances[name]; ok {
+		return nil
+	}
+
+	ts, err := NewHomeAssistant(name, uri)
+	if err != nil {
+		return err
+	}
+
+	instances[name] = &instance{
+		URI:         uri,
+		TokenSource: ts,
+	}
+
+	return nil
+}
diff --git a/util/templates/types.go b/util/templates/types.go
index 6fd91de0d..813ded760 100644
--- a/util/templates/types.go
+++ b/util/templates/types.go
@@ -199,6 +199,7 @@ type Param struct {
 	Usages      []string     `json:",omitempty"` // restrict param to these usage types, e.g. "battery" for home battery capacity
 	Type        ParamType    // string representation of the value type, "string" is default
 	Choice      []string     `json:",omitempty"` // defines a set of choices, e.g. "grid", "pv", "battery", "charge" for "usage"
+	Service     string       `json:",omitempty"` // defines a service to provide choices
 	AllInOne    bool         `json:"-"`          // defines if the defined usages can all be present in a single device
 
 	// TODO move somewhere else should not be part of the param definition
diff --git a/vehicle/homeassistant.go b/vehicle/homeassistant.go
index 9e34184ab..a84a8ff1a 100644
--- a/vehicle/homeassistant.go
+++ b/vehicle/homeassistant.go
@@ -23,10 +23,11 @@ func init() {
 
 // Constructor from YAML config
 func NewHomeAssistantVehicleFromConfig(other map[string]any) (api.Vehicle, error) {
-	var cc struct {
+	cc := struct {
 		embed   `mapstructure:",squash"`
-		URI     string
-		Token   string
+		_URI    string `mapstructure:"uri"`   // TODO deprecated
+		_Token  string `mapstructure:"token"` // TODO deprecated
+		Home    string
 		Sensors struct {
 			Soc        string // required
 			Range      string // optional
@@ -37,28 +38,25 @@ func NewHomeAssistantVehicleFromConfig(other map[string]any) (api.Vehicle, error
 			FinishTime string // optional
 		}
 		Services struct {
-			Start         string `mapstructure:"start_charging"` // script.*  optional
-			Stop          string `mapstructure:"stop_charging"`  // script.*  optional
-			Wakeup        string // script.*  optional
-			SetMaxCurrent string `mapstructure:"setMaxCurrent"` // number.* or input_number.* optional
+			Start         string `mapstructure:"start_charging"` // script.* optional
+			Stop          string `mapstructure:"stop_charging"`  // script.* optional
+			Wakeup        string // script.* optional
+			SetMaxCurrent string // number.* or input_number.* optional
 		}
+	}{
+		Home: "Home",
 	}
 
 	if err := util.DecodeOther(other, &cc); err != nil {
 		return nil, err
 	}
 
-	switch {
-	case cc.URI == "":
-		return nil, errors.New("missing uri")
-	case cc.Token == "":
-		return nil, errors.New("missing token")
-	case cc.Sensors.Soc == "":
+	if cc.Sensors.Soc == "" {
 		return nil, errors.New("missing soc sensor")
 	}
 
 	log := util.NewLogger("ha-vehicle")
-	conn, err := homeassistant.NewConnection(log, cc.URI, cc.Token)
+	conn, err := homeassistant.NewConnection(log, cc.Home)
 	if err != nil {
 		return nil, err
 	}