diff --git a/packages/cli/src/commands/commands.ts b/packages/cli/src/commands/commands.ts
index d61d21b4f2..b8101f4ae5 100644
--- a/packages/cli/src/commands/commands.ts
+++ b/packages/cli/src/commands/commands.ts
@@ -14,6 +14,10 @@ export const Commands = Spec.make(typeof OPENCODE_CLI_NAME === "string" ? OPENCO
       Flag.withDescription("Run with a private server instead of the background service"),
       Flag.withDefault(false),
     ),
+    server: Flag.string("server").pipe(
+      Flag.withDescription("Connect to a server URL instead of the background service"),
+      Flag.optional,
+    ),
     continue: Flag.boolean("continue").pipe(
       Flag.withAlias("c"),
       Flag.withDescription("Continue the last session"),
diff --git a/packages/cli/src/commands/handlers/api.ts b/packages/cli/src/commands/handlers/api.ts
index cf00394cb9..2ed0adb917 100644
--- a/packages/cli/src/commands/handlers/api.ts
+++ b/packages/cli/src/commands/handlers/api.ts
@@ -2,7 +2,8 @@ import { EOL } from "node:os"
 import { Effect, Option } from "effect"
 import { Commands } from "../commands"
 import { Runtime } from "../../framework/runtime"
-import { Daemon } from "../../services/daemon"
+import { Service } from "../../services/service"
+import type { Transport } from "@opencode-ai/client/service"
 
 const methods = new Set(["delete", "get", "head", "options", "patch", "post", "put"])
 
@@ -17,8 +18,7 @@ type OpenApi = {
 export default Runtime.handler(
   Commands.commands.api,
   Effect.fn("cli.api")(function* (input) {
-    const daemon = yield* Daemon.Service
-    const transport = yield* daemon.transport()
+    const transport = yield* Service.connect()
     const params = Option.getOrElse(input.param, () => ({}))
     const request = yield* resolveRequest(transport, input.request, params)
     const headers = new Headers(transport.headers)
@@ -58,7 +58,7 @@ export function rawRequest(input: readonly string[]) {
 }
 
 function resolveRequest(
-  transport: { url: string; headers: RequestInit["headers"] },
+  transport: Transport,
   input: readonly string[],
   params: Record<string, string>,
 ) {
diff --git a/packages/cli/src/commands/handlers/debug/agents.ts b/packages/cli/src/commands/handlers/debug/agents.ts
index 3a0c20cb06..fd0e1500c4 100644
--- a/packages/cli/src/commands/handlers/debug/agents.ts
+++ b/packages/cli/src/commands/handlers/debug/agents.ts
@@ -1,14 +1,15 @@
 import { EOL } from "os"
 import * as Effect from "effect/Effect"
+import { createOpencodeClient } from "@opencode-ai/sdk/v2/client"
 import { Commands } from "../../commands"
 import { Runtime } from "../../../framework/runtime"
-import { Daemon } from "../../../services/daemon"
+import { Service } from "../../../services/service"
 
 export default Runtime.handler(
   Commands.commands.debug.commands.agents,
   Effect.fn("cli.debug.agents")(function* () {
-    const daemon = yield* Daemon.Service
-    const client = yield* daemon.client()
+    const transport = yield* Service.connect()
+    const client = createOpencodeClient({ baseUrl: transport.url, headers: transport.headers })
     const response = yield* Effect.promise(() => client.v2.agent.list({ location: { directory: process.cwd() } }))
     process.stdout.write(
       JSON.stringify(
diff --git a/packages/cli/src/commands/handlers/default.ts b/packages/cli/src/commands/handlers/default.ts
index 193899d56e..c48a383534 100644
--- a/packages/cli/src/commands/handlers/default.ts
+++ b/packages/cli/src/commands/handlers/default.ts
@@ -1,9 +1,12 @@
 import { Commands } from "../commands"
 import { Runtime } from "../../framework/runtime"
-import { Effect, Option } from "effect"
-import { Daemon } from "../../services/daemon"
+import { Global } from "@opencode-ai/core/global"
+import { Effect, FileSystem, Option } from "effect"
+import { Service } from "../../services/service"
 import { Standalone } from "../../services/standalone"
 import { Updater } from "../../services/updater"
+import { basicAuth } from "@opencode-ai/client/service"
+import type { Transport } from "@opencode-ai/client/service"
 
 export default Runtime.handler(Commands, (input) =>
   Effect.gen(function* () {
@@ -11,18 +14,32 @@ export default Runtime.handler(Commands, (input) =>
     if (directory !== undefined) process.chdir(directory)
     const updater = yield* Updater.Service
     yield* updater.check().pipe(Effect.forkScoped)
-    const daemon = yield* Daemon.Service
-    const transport = yield* (input.standalone ? Standalone.transport() : daemon.transport())
+    const server = Option.getOrUndefined(input.server)
+    if (server !== undefined && input.standalone)
+      return yield* Effect.fail(new Error("--server and --standalone cannot be combined"))
+    const transport = yield* resolveTransport(server, input.standalone)
     const { runTui } = yield* Effect.promise(() => import("../../tui"))
-    yield* runTui(
-      transport,
-      { continue: input.continue, sessionID: Option.getOrUndefined(input.session) },
-      input.standalone
-        ? undefined
-        : async () => {
-            await Effect.runPromise(daemon.stop())
-            return Effect.runPromise(daemon.transport())
-          },
-    )
+    // The TUI re-runs discover whenever its event stream drops. For an explicit
+    // --server or a standalone child the transport is fixed, so reconnects
+    // retry the same address; for the managed service discovery re-reads the
+    // registration and may start a replacement.
+    const context = yield* Effect.context<FileSystem.FileSystem | Global.Service>()
+    const discover =
+      server !== undefined || input.standalone
+        ? () => Promise.resolve(transport)
+        : () => Effect.runPromise(Service.connect().pipe(Effect.provide(context)))
+    yield* runTui(transport, { continue: input.continue, sessionID: Option.getOrUndefined(input.session) }, discover)
   }),
 )
+
+function resolveTransport(server: string | undefined, standalone: boolean) {
+  if (server !== undefined) {
+    const password = process.env["OPENCODE_SERVER_PASSWORD"]
+    return Effect.succeed({
+      url: server,
+      headers: password ? basicAuth(password) : undefined,
+    } satisfies Transport)
+  }
+  if (standalone) return Standalone.transport()
+  return Service.connect()
+}
diff --git a/packages/cli/src/commands/handlers/mcp/auth.ts b/packages/cli/src/commands/handlers/mcp/auth.ts
index 2dc722076e..96affd21f8 100644
--- a/packages/cli/src/commands/handlers/mcp/auth.ts
+++ b/packages/cli/src/commands/handlers/mcp/auth.ts
@@ -1,9 +1,14 @@
 import { EOL } from "node:os"
 import { Effect } from "effect"
-import type { IntegrationAttemptStatus, IntegrationOAuthMethod, OpencodeClient } from "@opencode-ai/sdk/v2/client"
+import {
+  createOpencodeClient,
+  type IntegrationAttemptStatus,
+  type IntegrationOAuthMethod,
+  type OpencodeClient,
+} from "@opencode-ai/sdk/v2/client"
 import { Commands } from "../../commands"
 import { Runtime } from "../../../framework/runtime"
-import { Daemon } from "../../../services/daemon"
+import { Service } from "../../../services/service"
 import { resolveIntegration } from "./resolve"
 
 const location = { directory: process.cwd() }
@@ -11,8 +16,8 @@ const location = { directory: process.cwd() }
 export default Runtime.handler(
   Commands.commands.mcp.commands.auth,
   Effect.fn("cli.mcp.auth")(function* (input) {
-    const daemon = yield* Daemon.Service
-    const client = yield* daemon.client()
+    const transport = yield* Service.connect()
+    const client = createOpencodeClient({ baseUrl: transport.url, headers: transport.headers })
 
     const integration = yield* resolveIntegration(client, input.name, location)
     if (!integration)
diff --git a/packages/cli/src/commands/handlers/mcp/list.ts b/packages/cli/src/commands/handlers/mcp/list.ts
index 7866705ad1..e7e2dd3e38 100644
--- a/packages/cli/src/commands/handlers/mcp/list.ts
+++ b/packages/cli/src/commands/handlers/mcp/list.ts
@@ -1,15 +1,15 @@
 import { EOL } from "node:os"
 import * as Effect from "effect/Effect"
-import type { McpServer } from "@opencode-ai/sdk/v2/client"
+import { createOpencodeClient, type McpServer } from "@opencode-ai/sdk/v2/client"
 import { Commands } from "../../commands"
 import { Runtime } from "../../../framework/runtime"
-import { Daemon } from "../../../services/daemon"
+import { Service } from "../../../services/service"
 
 export default Runtime.handler(
   Commands.commands.mcp.commands.list,
   Effect.fn("cli.mcp.list")(function* () {
-    const daemon = yield* Daemon.Service
-    const client = yield* daemon.client()
+    const transport = yield* Service.connect()
+    const client = createOpencodeClient({ baseUrl: transport.url, headers: transport.headers })
     const response = yield* Effect.promise(() => client.v2.mcp.list({ location: { directory: process.cwd() } }))
     const servers = (response.data?.data ?? []).toSorted((a, b) => a.name.localeCompare(b.name))
     if (servers.length === 0) {
diff --git a/packages/cli/src/commands/handlers/mcp/logout.ts b/packages/cli/src/commands/handlers/mcp/logout.ts
index 6c4296ac38..1fa1e482dc 100644
--- a/packages/cli/src/commands/handlers/mcp/logout.ts
+++ b/packages/cli/src/commands/handlers/mcp/logout.ts
@@ -1,8 +1,9 @@
 import { EOL } from "node:os"
 import { Effect } from "effect"
+import { createOpencodeClient } from "@opencode-ai/sdk/v2/client"
 import { Commands } from "../../commands"
 import { Runtime } from "../../../framework/runtime"
-import { Daemon } from "../../../services/daemon"
+import { Service } from "../../../services/service"
 import { resolveIntegration } from "./resolve"
 
 const location = { directory: process.cwd() }
@@ -10,8 +11,8 @@ const location = { directory: process.cwd() }
 export default Runtime.handler(
   Commands.commands.mcp.commands.logout,
   Effect.fn("cli.mcp.logout")(function* (input) {
-    const daemon = yield* Daemon.Service
-    const client = yield* daemon.client()
+    const transport = yield* Service.connect()
+    const client = createOpencodeClient({ baseUrl: transport.url, headers: transport.headers })
 
     const integration = yield* resolveIntegration(client, input.name, location)
     if (!integration) {
diff --git a/packages/cli/src/commands/handlers/serve.ts b/packages/cli/src/commands/handlers/serve.ts
index fed803fa1e..bf406f2a89 100644
--- a/packages/cli/src/commands/handlers/serve.ts
+++ b/packages/cli/src/commands/handlers/serve.ts
@@ -13,7 +13,7 @@ import { ServerAuth } from "@opencode-ai/server/auth"
 import { createOpencodeClient } from "@opencode-ai/sdk/v2/client"
 import { Commands } from "../commands"
 import { Runtime } from "../../framework/runtime"
-import { Daemon } from "../../services/daemon"
+import { Service } from "../../services/service"
 import { Updater } from "../../services/updater"
 import { randomBytes } from "crypto"
 
@@ -23,12 +23,11 @@ export default Runtime.handler(
     if (input.service) yield* Effect.sync(() => process.chdir(Global.Path.home))
     return yield* Effect.scoped(
       Effect.gen(function* () {
-        const daemon = yield* Daemon.Service
         const standalonePassword = process.env.OPENCODE_SERVER_PASSWORD
         if (input.stdio) delete process.env.OPENCODE_SERVER_PASSWORD
-        const config = input.service ? yield* daemon.config() : {}
+        const config = input.service ? yield* Service.config() : {}
         const password = input.service
-          ? yield* daemon.password()
+          ? yield* Service.password()
           : standalonePassword || randomBytes(32).toString("base64url")
         if (!password) return yield* Effect.fail(new Error("Missing server password"))
         const hostname = Option.getOrUndefined(input.hostname) ?? config.hostname ?? "127.0.0.1"
@@ -44,7 +43,7 @@ export default Runtime.handler(
             headers: ServerAuth.headers({ password }),
           }).v2.health.get({}),
         )
-        if (input.service) yield* daemon.register(address)
+        if (input.service) yield* Service.register(address)
         const url = HttpServer.formatAddress(address)
         console.log(input.stdio ? JSON.stringify({ url }) : `server listening on ${url}`)
         if (!input.service && !input.stdio && !standalonePassword) console.log(`server password ${password}`)
diff --git a/packages/cli/src/commands/handlers/service/get.ts b/packages/cli/src/commands/handlers/service/get.ts
index aaaebf14a1..545ef7994f 100644
--- a/packages/cli/src/commands/handlers/service/get.ts
+++ b/packages/cli/src/commands/handlers/service/get.ts
@@ -3,12 +3,11 @@ import { Option } from "effect"
 import * as Effect from "effect/Effect"
 import { Commands } from "../../commands"
 import { Runtime } from "../../../framework/runtime"
-import { Daemon } from "../../../services/daemon"
+import { Service } from "../../../services/service"
 
 export default Runtime.handler(
   Commands.commands.service.commands.get,
   Effect.fn("cli.service.get")(function* (input) {
-    const daemon = yield* Daemon.Service
-    process.stdout.write((yield* daemon.get(Option.getOrUndefined(input.key))) + EOL)
+    process.stdout.write((yield* Service.get(Option.getOrUndefined(input.key))) + EOL)
   }),
 )
diff --git a/packages/cli/src/commands/handlers/service/restart.ts b/packages/cli/src/commands/handlers/service/restart.ts
index d348987d16..767ff65a5b 100644
--- a/packages/cli/src/commands/handlers/service/restart.ts
+++ b/packages/cli/src/commands/handlers/service/restart.ts
@@ -2,13 +2,12 @@ import { EOL } from "os"
 import * as Effect from "effect/Effect"
 import { Commands } from "../../commands"
 import { Runtime } from "../../../framework/runtime"
-import { Daemon } from "../../../services/daemon"
+import { Service } from "../../../services/service"
 
 export default Runtime.handler(
   Commands.commands.service.commands.restart,
   Effect.fn("cli.service.restart")(function* () {
-    const daemon = yield* Daemon.Service
-    yield* daemon.stop()
-    process.stdout.write((yield* daemon.start()) + EOL)
+    yield* Service.stop()
+    process.stdout.write((yield* Service.start()).url + EOL)
   }),
 )
diff --git a/packages/cli/src/commands/handlers/service/set.ts b/packages/cli/src/commands/handlers/service/set.ts
index d1181ef14a..39c0be6079 100644
--- a/packages/cli/src/commands/handlers/service/set.ts
+++ b/packages/cli/src/commands/handlers/service/set.ts
@@ -1,11 +1,11 @@
 import * as Effect from "effect/Effect"
 import { Commands } from "../../commands"
 import { Runtime } from "../../../framework/runtime"
-import { Daemon } from "../../../services/daemon"
+import { Service } from "../../../services/service"
 
 export default Runtime.handler(
   Commands.commands.service.commands.set,
   Effect.fn("cli.service.set")(function* (input) {
-    yield* (yield* Daemon.Service).set(input.key, input.value)
+    yield* Service.set(input.key, input.value)
   }),
 )
diff --git a/packages/cli/src/commands/handlers/service/start.ts b/packages/cli/src/commands/handlers/service/start.ts
index 0d6fbaada9..58807c8fea 100644
--- a/packages/cli/src/commands/handlers/service/start.ts
+++ b/packages/cli/src/commands/handlers/service/start.ts
@@ -2,11 +2,11 @@ import { EOL } from "os"
 import * as Effect from "effect/Effect"
 import { Commands } from "../../commands"
 import { Runtime } from "../../../framework/runtime"
-import { Daemon } from "../../../services/daemon"
+import { Service } from "../../../services/service"
 
 export default Runtime.handler(
   Commands.commands.service.commands.start,
   Effect.fn("cli.service.start")(function* () {
-    process.stdout.write((yield* (yield* Daemon.Service).start()) + EOL)
+    process.stdout.write((yield* Service.start()).url + EOL)
   }),
 )
diff --git a/packages/cli/src/commands/handlers/service/status.ts b/packages/cli/src/commands/handlers/service/status.ts
index 779d456c78..9fc27505f6 100644
--- a/packages/cli/src/commands/handlers/service/status.ts
+++ b/packages/cli/src/commands/handlers/service/status.ts
@@ -2,12 +2,12 @@ import { EOL } from "os"
 import * as Effect from "effect/Effect"
 import { Commands } from "../../commands"
 import { Runtime } from "../../../framework/runtime"
-import { Daemon } from "../../../services/daemon"
+import { Service } from "../../../services/service"
 
 export default Runtime.handler(
   Commands.commands.service.commands.status,
   Effect.fn("cli.service.status")(function* () {
-    const url = yield* (yield* Daemon.Service).status()
-    process.stdout.write((url ? url : "stopped") + EOL)
+    const found = yield* Service.discover()
+    process.stdout.write((found ? found.url : "stopped") + EOL)
   }),
 )
diff --git a/packages/cli/src/commands/handlers/service/stop.ts b/packages/cli/src/commands/handlers/service/stop.ts
index 8da9b04cff..1336cdbe1a 100644
--- a/packages/cli/src/commands/handlers/service/stop.ts
+++ b/packages/cli/src/commands/handlers/service/stop.ts
@@ -1,11 +1,11 @@
 import * as Effect from "effect/Effect"
 import { Commands } from "../../commands"
 import { Runtime } from "../../../framework/runtime"
-import { Daemon } from "../../../services/daemon"
+import { Service } from "../../../services/service"
 
 export default Runtime.handler(
   Commands.commands.service.commands.stop,
   Effect.fn("cli.service.stop")(function* () {
-    yield* (yield* Daemon.Service).stop()
+    yield* Service.stop()
   }),
 )
diff --git a/packages/cli/src/commands/handlers/service/unset.ts b/packages/cli/src/commands/handlers/service/unset.ts
index f16bbe32cc..83b5c2b172 100644
--- a/packages/cli/src/commands/handlers/service/unset.ts
+++ b/packages/cli/src/commands/handlers/service/unset.ts
@@ -1,11 +1,11 @@
 import * as Effect from "effect/Effect"
 import { Commands } from "../../commands"
 import { Runtime } from "../../../framework/runtime"
-import { Daemon } from "../../../services/daemon"
+import { Service } from "../../../services/service"
 
 export default Runtime.handler(
   Commands.commands.service.commands.unset,
   Effect.fn("cli.service.unset")(function* (input) {
-    yield* (yield* Daemon.Service).unset(input.key)
+    yield* Service.unset(input.key)
   }),
 )
diff --git a/packages/cli/src/framework/runtime.ts b/packages/cli/src/framework/runtime.ts
index 44ed78ea72..902c89d716 100644
--- a/packages/cli/src/framework/runtime.ts
+++ b/packages/cli/src/framework/runtime.ts
@@ -1,9 +1,9 @@
 import * as Effect from "effect/Effect"
 import * as Command from "effect/unstable/cli/Command"
 import { Spec } from "./spec"
-import { Daemon } from "../services/daemon"
+import { Global } from "@opencode-ai/core/global"
 import { Updater } from "../services/updater"
-import { Scope } from "effect"
+import { FileSystem, Scope } from "effect"
 
 export type Input<Value> =
   Value extends Spec.Node<infer _Name, infer Command, infer _Commands>
@@ -12,11 +12,11 @@ export type Input<Value> =
       ? Input
       : never
 
-type RuntimeHandler = (input: unknown) => Effect.Effect<void, unknown, Daemon.Service | Updater.Service | Scope.Scope>
+type RuntimeHandler = (input: unknown) => Effect.Effect<void, unknown, FileSystem.FileSystem | Global.Service | Updater.Service | Scope.Scope>
 type Loader<Node extends Spec.Any> = () => Promise<{
-  default: (input: Input<Node>) => Effect.Effect<void, any, Daemon.Service | Updater.Service | Scope.Scope>
+  default: (input: Input<Node>) => Effect.Effect<void, any, FileSystem.FileSystem | Global.Service | Updater.Service | Scope.Scope>
 }>
-type ProvidedCommand = Command.Command<string, unknown, unknown, unknown, Daemon.Service | Updater.Service | Scope.Scope>
+type ProvidedCommand = Command.Command<string, unknown, unknown, unknown, FileSystem.FileSystem | Global.Service | Updater.Service | Scope.Scope>
 
 export type Handlers<Node extends Spec.Any> = keyof Node["commands"] extends never
   ? Loader<Node>
diff --git a/packages/cli/src/index.ts b/packages/cli/src/index.ts
index 792261fac3..071fd37e1a 100755
--- a/packages/cli/src/index.ts
+++ b/packages/cli/src/index.ts
@@ -7,7 +7,6 @@ import * as Effect from "effect/Effect"
 import { Layer, Logger, References } from "effect"
 import { Commands } from "./commands/commands"
 import { Runtime } from "./framework/runtime"
-import { Daemon } from "./services/daemon"
 import { Logging } from "@opencode-ai/core/observability/logging"
 import { Updater } from "./services/updater"
 import { InstallationChannel, InstallationVersion, InstallationLocal } from "@opencode-ai/core/installation/version"
@@ -50,7 +49,6 @@ const Handlers = Runtime.handlers(Commands, {
 Effect.logInfo("cli starting", { version: InstallationVersion, channel: InstallationChannel, local: InstallationLocal }).pipe(
   Effect.flatMap(() => Runtime.run(Commands, Handlers, { version: InstallationVersion })),
   Effect.annotateLogs({ role: "cli" }),
-  Effect.provide(Daemon.layer),
   Effect.provide(Updater.layer),
   Effect.provide(AppNodeBuilder.build(LayerNode.group([Global.node, AppProcess.node]))),
   Effect.provide(LoggingLayer),
diff --git a/packages/cli/src/services/daemon.ts b/packages/cli/src/services/daemon.ts
deleted file mode 100644
index 1c91bcb7f7..0000000000
--- a/packages/cli/src/services/daemon.ts
+++ /dev/null
@@ -1,323 +0,0 @@
-import { Global } from "@opencode-ai/core/global"
-import { InstallationChannel, InstallationVersion } from "@opencode-ai/core/installation/version"
-import { createOpencodeClient } from "@opencode-ai/sdk/v2/client"
-import { ServerAuth } from "@opencode-ai/server/auth"
-import { Context, Effect, FileSystem, Layer, Option, Schedule, Schema, Scope } from "effect"
-import { HttpServer } from "effect/unstable/http"
-import { randomBytes, randomUUID } from "crypto"
-import { spawn } from "node:child_process"
-import path from "path"
-
-export interface Interface {
-  readonly client: () => Effect.Effect<ReturnType<typeof createOpencodeClient>, unknown>
-  readonly transport: () => Effect.Effect<{ url: string; headers: RequestInit["headers"] }, unknown>
-  readonly start: () => Effect.Effect<string, Error>
-  readonly status: () => Effect.Effect<string | undefined>
-  readonly stop: () => Effect.Effect<void, unknown>
-  readonly password: (value?: string) => Effect.Effect<string, unknown>
-  readonly config: () => Effect.Effect<ServiceConfig, unknown>
-  readonly get: (key?: string) => Effect.Effect<string, unknown>
-  readonly set: (key: string, value: string) => Effect.Effect<void, unknown>
-  readonly unset: (key: string) => Effect.Effect<void, unknown>
-  readonly register: (address: HttpServer.Address) => Effect.Effect<void, unknown, Scope.Scope>
-}
-
-export class Service extends Context.Service<Service, Interface>()("@opencode/cli/Daemon") {}
-
-const Registration = Schema.Struct({
-  id: Schema.optional(Schema.String),
-  version: Schema.optional(Schema.String),
-  url: Schema.String,
-  pid: Schema.Int.check(Schema.isGreaterThan(0)),
-})
-type Registration = typeof Registration.Type
-
-const ServiceConfig = Schema.Struct({
-  hostname: Schema.optional(Schema.String),
-  port: Schema.optional(Schema.Int.check(Schema.isGreaterThanOrEqualTo(1), Schema.isLessThanOrEqualTo(65_535))),
-  password: Schema.optional(Schema.String),
-  autostart: Schema.optional(Schema.Boolean),
-})
-export type ServiceConfig = typeof ServiceConfig.Type
-
-const serviceConfigKeys = ["hostname", "port", "password", "autostart"] as const
-type ServiceConfigKey = (typeof serviceConfigKeys)[number]
-
-function serviceConfigKey(key: string): ServiceConfigKey {
-  if (serviceConfigKeys.includes(key as ServiceConfigKey)) return key as ServiceConfigKey
-  throw new Error(`Unknown service config key: ${key}`)
-}
-
-function sameRegistration(left: Registration, right: Registration) {
-  return left.id === right.id && left.version === right.version && left.url === right.url && left.pid === right.pid
-}
-
-export const layer = Layer.effect(
-  Service,
-  Effect.gen(function* () {
-    const fs = yield* FileSystem.FileSystem
-    const global = yield* Global.Service
-    const directory = global.state
-    const filename = InstallationChannel === "local" ? "service-local.json" : "service.json"
-    const file = path.join(directory, filename)
-    const configFile = path.join(global.config, filename)
-    const decodeRegistration = Schema.decodeUnknownEffect(Schema.fromJsonString(Registration))
-    const decodeServiceConfig = Schema.decodeUnknownEffect(Schema.fromJsonString(ServiceConfig))
-
-    const config = Effect.fn("cli.daemon.config")(function* () {
-      return yield* fs.readFileString(configFile).pipe(
-        Effect.flatMap(decodeServiceConfig),
-        Effect.catch(() => Effect.succeed({} as ServiceConfig)),
-      )
-    })
-
-    const writeConfig = Effect.fn("cli.daemon.writeConfig")(function* (value: ServiceConfig) {
-      const temp = configFile + ".tmp"
-      yield* fs.makeDirectory(path.dirname(configFile), { recursive: true })
-      yield* fs.writeFileString(temp, JSON.stringify(value, null, 2) + "\n", { mode: 0o600 })
-      yield* fs.rename(temp, configFile)
-    })
-
-    const password = Effect.fn("cli.daemon.password")(function* (value?: string) {
-      const existing = yield* config()
-      if (value === undefined && existing.password) return existing.password
-      const next = value ?? randomBytes(32).toString("base64url")
-
-      // Keep one private credential across server restarts so discovered clients
-      // can reconnect without exposing a password flag or environment variable.
-      yield* writeConfig({ ...existing, password: next })
-      return next
-    })
-
-    const get = Effect.fn("cli.daemon.get")(function* (key?: string) {
-      if (key === undefined) {
-        const { password: _password, ...safe } = yield* config()
-        return JSON.stringify(safe, null, 2)
-      }
-      switch (serviceConfigKey(key)) {
-        case "hostname": {
-          return (yield* config()).hostname ?? ""
-        }
-        case "port": {
-          const port = (yield* config()).port
-          return port === undefined ? "" : String(port)
-        }
-        case "password": {
-          return yield* password()
-        }
-        case "autostart": {
-          const autostart = (yield* config()).autostart
-          return autostart === undefined ? "" : String(autostart)
-        }
-      }
-    })
-
-    const set = Effect.fn("cli.daemon.set")(function* (key: string, value: string) {
-      switch (serviceConfigKey(key)) {
-        case "hostname": {
-          yield* stop()
-          yield* writeConfig({ ...(yield* config()), hostname: value })
-          return
-        }
-        case "port": {
-          const port = Number(value)
-          if (!Number.isInteger(port) || port < 1 || port > 65_535) throw new Error("Port must be between 1 and 65535")
-          yield* stop()
-          yield* writeConfig({ ...(yield* config()), port })
-          return
-        }
-        case "password": {
-          yield* stop()
-          yield* password(value)
-          return
-        }
-        case "autostart": {
-          if (value !== "true" && value !== "false") throw new Error("Autostart must be true or false")
-          yield* writeConfig({ ...(yield* config()), autostart: value === "true" })
-          return
-        }
-      }
-    })
-
-    const unset = Effect.fn("cli.daemon.unset")(function* (key: string) {
-      switch (serviceConfigKey(key)) {
-        case "hostname": {
-          yield* stop()
-          const { hostname: _hostname, ...next } = yield* config()
-          yield* writeConfig(next)
-          return
-        }
-        case "port": {
-          yield* stop()
-          const { port: _port, ...next } = yield* config()
-          yield* writeConfig(next)
-          return
-        }
-        case "password": {
-          yield* stop()
-          const { password: _password, ...next } = yield* config()
-          yield* writeConfig(next)
-          return
-        }
-        case "autostart": {
-          const { autostart: _autostart, ...next } = yield* config()
-          yield* writeConfig(next)
-          return
-        }
-      }
-    })
-
-    const registration = Effect.fnUntraced(function* () {
-      return yield* fs.readFileString(file).pipe(Effect.flatMap(decodeRegistration))
-    })
-
-    const createClient = Effect.fnUntraced(function* (url: string) {
-      return createOpencodeClient({ baseUrl: url, headers: ServerAuth.headers({ password: yield* password() }) })
-    })
-
-    const healthy = Effect.fnUntraced(function* () {
-      const info = yield* registration()
-      const client = yield* createClient(info.url)
-      const response = yield* Effect.tryPromise(() => client.v2.health.get({ signal: AbortSignal.timeout(2_000) }))
-      if (response.data?.healthy === true) return info
-      return yield* Effect.fail(new Error("Registered server is not healthy"))
-    })
-
-    const remoteTransport = Effect.fn("cli.daemon.remoteTransport")(function* (input: ServiceConfig) {
-      const url = serviceURL(input)
-      const headers = ServerAuth.headers({ password: input.password })
-      const response = yield* Effect.tryPromise(() =>
-        createOpencodeClient({ baseUrl: url, headers }).v2.health.get({ signal: AbortSignal.timeout(2_000) }),
-      )
-      if (response.data?.healthy === true) return { url, headers }
-      return yield* Effect.fail(new Error(`Server is not healthy: ${url}`))
-    })
-
-    const compatible = Effect.fnUntraced(function* () {
-      const info = yield* healthy()
-      if (info.version === InstallationVersion) return info
-      return yield* Effect.fail(new Error("Registered server version does not match the client"))
-    })
-
-    const signal = (pid: number, signal: NodeJS.Signals) =>
-      Effect.try({ try: () => process.kill(pid, signal), catch: (cause) => cause }).pipe(Effect.ignore)
-
-    const awaitStopped = Effect.fnUntraced(function* (pid: number) {
-      const running = yield* Effect.try({ try: () => process.kill(pid, 0), catch: () => false }).pipe(
-        Effect.orElseSucceed(() => false),
-      )
-      if (!running) return true
-      return yield* Effect.fail(new Error(`Server process ${pid} is still running`))
-    })
-
-    const stopProcess = Effect.fnUntraced(function* (info: Registration) {
-      const current = yield* healthy().pipe(Effect.option)
-      if (Option.isNone(current) || !sameRegistration(current.value, info)) return
-
-      yield* signal(info.pid, "SIGTERM")
-      const stopped = yield* awaitStopped(info.pid).pipe(
-        Effect.retry(Schedule.spaced("50 millis").pipe(Schedule.both(Schedule.recurs(100)))),
-        Effect.option,
-      )
-      if (Option.isSome(stopped)) return
-
-      const latest = yield* healthy().pipe(Effect.option)
-      if (Option.isNone(latest) || !sameRegistration(latest.value, info)) return
-      yield* signal(info.pid, "SIGKILL")
-      yield* awaitStopped(info.pid).pipe(
-        Effect.retry(Schedule.spaced("50 millis").pipe(Schedule.both(Schedule.recurs(100)))),
-      )
-    })
-
-    const start = Effect.fn("cli.daemon.start")(function* () {
-      const existing = yield* healthy().pipe(Effect.option)
-      const found = Option.getOrUndefined(existing)
-      const compiled = path.basename(process.execPath).replace(/\.exe$/, "") !== "bun"
-      if (found?.version === InstallationVersion) return found.url
-      if (found) yield* stopProcess(found).pipe(Effect.ignore)
-
-      const entrypoint = compiled ? undefined : process.argv[1]
-      if (!compiled && entrypoint === undefined)
-        return yield* Effect.fail(new Error("Failed to resolve CLI entrypoint"))
-      yield* Effect.try({
-        try: () => {
-          spawn(process.execPath, [...(entrypoint ? [entrypoint] : []), "serve", "--service"], {
-            detached: true,
-            stdio: "ignore",
-          }).unref()
-        },
-        catch: (cause) => new Error("Failed to start server", { cause }),
-      })
-
-      return yield* compatible().pipe(
-        Effect.retry(Schedule.spaced("50 millis").pipe(Schedule.both(Schedule.recurs(100)))),
-        Effect.map((info) => info.url),
-        Effect.mapError(() => new Error("Failed to start server")),
-      )
-    })
-
-    const transport = Effect.fn("cli.daemon.transport")(function* () {
-      const current = yield* config()
-      if (current.autostart === false) return yield* remoteTransport(current)
-      return { url: yield* start(), headers: ServerAuth.headers({ password: yield* password() }) }
-    })
-
-    const client = Effect.fn("cli.daemon.client")(function* () {
-      const connection = yield* transport()
-      return createOpencodeClient({ baseUrl: connection.url, headers: connection.headers })
-    })
-
-    const status = Effect.fn("cli.daemon.status")(function* () {
-      const existing = yield* healthy().pipe(Effect.option)
-      const found = Option.getOrUndefined(existing)
-      if (found?.version === InstallationVersion) return found.url
-      if (found) return undefined
-      yield* fs.remove(file).pipe(Effect.ignore)
-      return undefined
-    })
-
-    const stop = Effect.fn("cli.daemon.stop")(function* () {
-      const existing = yield* healthy().pipe(Effect.option)
-      // A stale registration may point at a PID that has since been reused by
-      // another process. Only signal the PID after authenticating the server.
-      if (Option.isNone(existing)) return yield* fs.remove(file).pipe(Effect.ignore)
-      yield* stopProcess(existing.value)
-      yield* fs.remove(file).pipe(Effect.ignore)
-    })
-
-    const register = Effect.fn("cli.daemon.register")(function* (address: HttpServer.Address) {
-      const id = randomUUID()
-      const temp = file + "." + id + ".tmp"
-      yield* fs.makeDirectory(directory, { recursive: true })
-      yield* fs.writeFileString(
-        temp,
-        JSON.stringify({ id, version: InstallationVersion, url: HttpServer.formatAddress(address), pid: process.pid }),
-        { mode: 0o600 },
-      )
-      yield* fs.rename(temp, file)
-      yield* registration().pipe(
-        Effect.flatMap((info) => (info.id === id ? Effect.void : signal(process.pid, "SIGTERM"))),
-        Effect.catch(() => signal(process.pid, "SIGTERM")),
-        Effect.repeat(Schedule.spaced("10 seconds")),
-        Effect.forkScoped,
-      )
-      yield* Effect.addFinalizer(() =>
-        registration().pipe(
-          Effect.flatMap((info) => (info.id === id ? fs.remove(file) : Effect.void)),
-          Effect.ignore,
-        ),
-      )
-    })
-
-    return Service.of({ client, transport, start, status, stop, password, config, get, set, unset, register })
-  }),
-)
-
-function serviceURL(config: ServiceConfig) {
-  const hostname = config.hostname ?? "127.0.0.1"
-  const result = new URL(`http://${hostname.includes(":") && !hostname.startsWith("[") ? `[${hostname}]` : hostname}`)
-  result.port = String(config.port ?? 4096)
-  return result.toString()
-}
-
-export * as Daemon from "./daemon"
diff --git a/packages/cli/src/services/service.ts b/packages/cli/src/services/service.ts
new file mode 100644
index 0000000000..e7801fd134
--- /dev/null
+++ b/packages/cli/src/services/service.ts
@@ -0,0 +1,203 @@
+import { Global } from "@opencode-ai/core/global"
+import { InstallationChannel, InstallationVersion } from "@opencode-ai/core/installation/version"
+import { ServiceEffect } from "@opencode-ai/client/service/effect"
+import { Effect, FileSystem, Schedule, Schema } from "effect"
+import { HttpServer } from "effect/unstable/http"
+import { randomBytes, randomUUID } from "crypto"
+import path from "path"
+
+// Binds the client package's service operations to this CLI: which
+// registration file (by channel), which version, and how to spawn opencode.
+// Also owns the service config file and the server-side registration write.
+
+const ServiceConfig = Schema.Struct({
+  hostname: Schema.optional(Schema.String),
+  port: Schema.optional(Schema.Int.check(Schema.isGreaterThanOrEqualTo(1), Schema.isLessThanOrEqualTo(65_535))),
+  password: Schema.optional(Schema.String),
+})
+export type ServiceConfig = typeof ServiceConfig.Type
+
+const serviceConfigKeys = ["hostname", "port", "password"] as const
+type ServiceConfigKey = (typeof serviceConfigKeys)[number]
+
+const decodeServiceConfig = Schema.decodeUnknownEffect(Schema.fromJsonString(ServiceConfig))
+
+function serviceConfigKey(key: string): ServiceConfigKey {
+  if (serviceConfigKeys.includes(key as ServiceConfigKey)) return key as ServiceConfigKey
+  throw new Error(`Unknown service config key: ${key}`)
+}
+
+const env = Effect.gen(function* () {
+  const fs = yield* FileSystem.FileSystem
+  const global = yield* Global.Service
+  const filename = InstallationChannel === "local" ? "service-local.json" : "service.json"
+  return {
+    fs,
+    stateDir: global.state,
+    file: path.join(global.state, filename),
+    configFile: path.join(global.config, filename),
+  }
+})
+
+const options = Effect.fnUntraced(function* () {
+  const { file } = yield* env
+  const compiled = path.basename(process.execPath).replace(/\.exe$/, "") !== "bun"
+  const entrypoint = compiled ? undefined : process.argv[1]
+  if (!compiled && entrypoint === undefined) return yield* Effect.fail(new Error("Failed to resolve CLI entrypoint"))
+  return {
+    file,
+    version: InstallationVersion,
+    command: [process.execPath, ...(entrypoint ? [entrypoint] : []), "serve", "--service"],
+  }
+})
+
+export const discover = Effect.fn("cli.service.discover")(function* () {
+  const found = yield* ServiceEffect.discover(yield* options())
+  return found?.transport
+})
+
+export const start = Effect.fn("cli.service.start")(function* () {
+  return yield* ServiceEffect.start(yield* options())
+})
+
+export const connect = Effect.fn("cli.service.connect")(function* () {
+  return yield* ServiceEffect.connect(yield* options())
+})
+
+export const stop = Effect.fn("cli.service.stop")(function* () {
+  return yield* ServiceEffect.stop(yield* options())
+})
+
+export const config = Effect.fn("cli.service.config")(function* () {
+  const { fs, configFile } = yield* env
+  return yield* fs.readFileString(configFile).pipe(
+    Effect.flatMap(decodeServiceConfig),
+    Effect.catch(() => Effect.succeed({} as ServiceConfig)),
+  )
+})
+
+const writeConfig = Effect.fn("cli.service.writeConfig")(function* (value: ServiceConfig) {
+  const { fs, configFile } = yield* env
+  const temp = configFile + ".tmp"
+  yield* fs.makeDirectory(path.dirname(configFile), { recursive: true })
+  yield* fs.writeFileString(temp, JSON.stringify(value, null, 2) + "\n", { mode: 0o600 })
+  yield* fs.rename(temp, configFile)
+})
+
+export const password = Effect.fn("cli.service.password")(function* (value?: string) {
+  const existing = yield* config()
+  if (value === undefined && existing.password) return existing.password
+  const next = value ?? randomBytes(32).toString("base64url")
+
+  // Keep one private credential across server restarts so discovered clients
+  // can reconnect without exposing a password flag or environment variable.
+  yield* writeConfig({ ...existing, password: next })
+  return next
+})
+
+export const get = Effect.fn("cli.service.get")(function* (key?: string) {
+  if (key === undefined) {
+    const { password: _password, ...safe } = yield* config()
+    return JSON.stringify(safe, null, 2)
+  }
+  switch (serviceConfigKey(key)) {
+    case "hostname": {
+      return (yield* config()).hostname ?? ""
+    }
+    case "port": {
+      const port = (yield* config()).port
+      return port === undefined ? "" : String(port)
+    }
+    case "password": {
+      return yield* password()
+    }
+  }
+})
+
+export const set = Effect.fn("cli.service.set")(function* (key: string, value: string) {
+  switch (serviceConfigKey(key)) {
+    case "hostname": {
+      yield* stop()
+      yield* writeConfig({ ...(yield* config()), hostname: value })
+      return
+    }
+    case "port": {
+      const port = Number(value)
+      if (!Number.isInteger(port) || port < 1 || port > 65_535) throw new Error("Port must be between 1 and 65535")
+      yield* stop()
+      yield* writeConfig({ ...(yield* config()), port })
+      return
+    }
+    case "password": {
+      yield* stop()
+      yield* password(value)
+      return
+    }
+  }
+})
+
+export const unset = Effect.fn("cli.service.unset")(function* (key: string) {
+  switch (serviceConfigKey(key)) {
+    case "hostname": {
+      yield* stop()
+      const { hostname: _hostname, ...next } = yield* config()
+      yield* writeConfig(next)
+      return
+    }
+    case "port": {
+      yield* stop()
+      const { port: _port, ...next } = yield* config()
+      yield* writeConfig(next)
+      return
+    }
+    case "password": {
+      yield* stop()
+      const { password: _password, ...next } = yield* config()
+      yield* writeConfig(next)
+      return
+    }
+  }
+})
+
+// Server-side half of the registration protocol, run by `serve --service` at
+// boot. The registration embeds the password so the file alone is enough for
+// any client to discover and authenticate. service.json arbitrates ownership
+// after concurrent starts; it is not a startup lock: the atomic rename elects
+// the latest writer, the watcher self-evicts losers, and the finalizer
+// id-guard keeps an exiting server from deleting its successor's registration.
+export const register = Effect.fn("cli.service.register")(function* (address: HttpServer.Address) {
+  const { fs, stateDir, file } = yield* env
+  const id = randomUUID()
+  const secret = yield* password()
+  const temp = file + "." + id + ".tmp"
+  yield* fs.makeDirectory(stateDir, { recursive: true })
+  yield* fs.writeFileString(
+    temp,
+    JSON.stringify({
+      id,
+      version: InstallationVersion,
+      url: HttpServer.formatAddress(address),
+      pid: process.pid,
+      password: secret,
+    }),
+    { mode: 0o600 },
+  )
+  yield* fs.rename(temp, file)
+  yield* ServiceEffect.readRegistration(file).pipe(
+    Effect.flatMap((info) =>
+      info?.id === id
+        ? Effect.void
+        : Effect.try({ try: () => process.kill(process.pid, "SIGTERM"), catch: (cause) => cause }).pipe(Effect.ignore),
+    ),
+    Effect.repeat(Schedule.spaced("10 seconds")),
+    Effect.forkScoped,
+  )
+  yield* Effect.addFinalizer(() =>
+    ServiceEffect.readRegistration(file).pipe(
+      Effect.flatMap((info) => (info?.id === id ? fs.remove(file) : Effect.void)),
+      Effect.ignore,
+    ),
+  )
+})
+
+export * as Service from "./service"
diff --git a/packages/cli/src/tui.ts b/packages/cli/src/tui.ts
index 43c9fa3086..234f69d729 100644
--- a/packages/cli/src/tui.ts
+++ b/packages/cli/src/tui.ts
@@ -5,12 +5,11 @@ import { AppNodeBuilder } from "@opencode-ai/core/effect/app-node-builder"
 import { Global } from "@opencode-ai/core/global"
 import { loadBuiltinPlugins } from "@opencode-ai/tui/builtins"
 import { OpenCode } from "@opencode-ai/client"
+import type { Transport } from "@opencode-ai/client/service"
 import { createOpencodeClient } from "@opencode-ai/sdk/v2/client"
 import type { Args } from "@opencode-ai/tui/context/args"
 
-type Transport = { url: string; headers: RequestInit["headers"] }
-
-export function runTui(transport: Transport, args: Args, reload?: () => Promise<Transport>) {
+export function runTui(transport: Transport, args: Args, discover?: () => Promise<Transport>) {
   const config = TuiConfig.resolve({}, { terminalSuspend: false })
   let disposeSlots: (() => void) | undefined
   return Effect.gen(function* () {
@@ -25,9 +24,9 @@ export function runTui(transport: Transport, args: Args, reload?: () => Promise<
     return yield* run({
       client: createOpencodeClient({ ...options, directory }),
       api,
-      reload: reload
+      discover: discover
         ? async () => {
-            const next = await reload()
+            const next = await discover()
             return {
               client: createOpencodeClient({ baseUrl: next.url, headers: next.headers, directory }),
               api: OpenCode.make({ baseUrl: next.url, headers: next.headers }),
diff --git a/packages/cli/test/daemon.test.ts b/packages/cli/test/service.test.ts
similarity index 77%
rename from packages/cli/test/daemon.test.ts
rename to packages/cli/test/service.test.ts
index 138544fdf4..6a4330ac76 100644
--- a/packages/cli/test/daemon.test.ts
+++ b/packages/cli/test/service.test.ts
@@ -5,23 +5,19 @@ import { Effect } from "effect"
 import fs from "node:fs/promises"
 import os from "node:os"
 import path from "node:path"
-import { Daemon } from "../src/services/daemon"
+import { Service } from "../src/services/service"
 
 test("local channel stores service config with the local service filename", async () => {
-  const root = await fs.mkdtemp(path.join(os.tmpdir(), "opencode-daemon-"))
+  const root = await fs.mkdtemp(path.join(os.tmpdir(), "opencode-service-"))
   try {
     await Effect.runPromise(
-      Effect.gen(function* () {
-        const daemon = yield* Daemon.Service
-        yield* daemon.set("autostart", "false")
-      }).pipe(
-        Effect.provide(Daemon.layer),
+      Service.set("hostname", "127.0.0.2").pipe(
         Effect.provide(Global.layerWith({ config: path.join(root, "config"), state: path.join(root, "state") })),
         Effect.provide(NodeFileSystem.layer),
       ),
     )
     expect(await Bun.file(path.join(root, "config", "service-local.json")).json()).toEqual({
-      autostart: false,
+      hostname: "127.0.0.2",
     })
     expect(await Bun.file(path.join(root, "config", "service.json")).exists()).toBe(false)
   } finally {
diff --git a/packages/client/package.json b/packages/client/package.json
index 4f2445ca9d..0b93fa532a 100644
--- a/packages/client/package.json
+++ b/packages/client/package.json
@@ -6,7 +6,9 @@
   "license": "MIT",
   "exports": {
     ".": "./src/index.ts",
-    "./effect": "./src/effect.ts"
+    "./effect": "./src/effect.ts",
+    "./service": "./src/service/index.ts",
+    "./service/effect": "./src/service/effect.ts"
   },
   "scripts": {
     "generate": "bun run script/build.ts",
diff --git a/packages/client/src/service/effect.ts b/packages/client/src/service/effect.ts
new file mode 100644
index 0000000000..8f58fc786a
--- /dev/null
+++ b/packages/client/src/service/effect.ts
@@ -0,0 +1,22 @@
+import { Effect } from "effect"
+import * as service from "./index.js"
+
+export type { Transport, Discover, Registration, LocalService, ServiceOptions } from "./index.js"
+
+export { basicAuth } from "./index.js"
+
+export const readRegistration = (file?: string) => Effect.promise(() => service.readRegistration(file))
+export const discover = (options?: service.ServiceOptions) => Effect.promise(() => service.discover(options))
+export const stop = (options?: service.ServiceOptions) => Effect.promise(() => service.stop(options))
+export const start = (options?: service.ServiceOptions) =>
+  Effect.tryPromise({
+    try: () => service.start(options),
+    catch: (cause) => new Error("Failed to start server", { cause }),
+  })
+export const connect = (options?: service.ServiceOptions) =>
+  Effect.tryPromise({
+    try: () => service.connect(options),
+    catch: (cause) => new Error("Failed to connect to server", { cause }),
+  })
+
+export * as ServiceEffect from "./effect.js"
diff --git a/packages/client/src/service/index.ts b/packages/client/src/service/index.ts
new file mode 100644
index 0000000000..2222dd3905
--- /dev/null
+++ b/packages/client/src/service/index.ts
@@ -0,0 +1,172 @@
+import { spawn } from "node:child_process"
+import { readFile, rm } from "node:fs/promises"
+import { homedir } from "node:os"
+import { join } from "node:path"
+
+// Everything a client needs to connect to an opencode server and to find or
+// start the local background service.
+//
+// The service daemon advertises itself through a registration file in the
+// user's state directory: url, pid, version, and the private password, with
+// 0600 permissions. That file is the complete discovery contract — reading it
+// is all a client needs to connect. The daemon's own configuration (port,
+// persisted password) is CLI-owned and never read here.
+
+export type Transport = {
+  readonly url: string
+  readonly headers?: RequestInit["headers"]
+}
+
+export type Discover = () => Promise<Transport | undefined>
+
+export function basicAuth(password: string): RequestInit["headers"] {
+  return { authorization: "Basic " + btoa("opencode:" + password) }
+}
+
+export type Registration = {
+  readonly id?: string
+  readonly version?: string
+  readonly url: string
+  readonly pid: number
+  readonly password?: string
+}
+
+export type LocalService = {
+  readonly registration: Registration
+  readonly transport: Transport
+}
+
+export type ServiceOptions = {
+  // Absolute path to the service registration file. Defaults to
+  // opencode/service.json in the XDG state directory.
+  readonly file?: string
+  // When set, discovery only returns a server reporting this exact version,
+  // and start() replaces a healthy server whose version differs.
+  readonly version?: string
+  // Argv used to spawn the service. Defaults to ["opencode", "serve",
+  // "--service"] resolved from PATH.
+  readonly command?: ReadonlyArray<string>
+  readonly timeout?: number
+}
+
+export function defaultRegistrationFile(): string {
+  const state = process.env["XDG_STATE_HOME"] ?? join(homedir(), ".local", "state")
+  return join(state, "opencode", "service.json")
+}
+
+export async function readRegistration(file?: string): Promise<Registration | undefined> {
+  const text = await readFile(file ?? defaultRegistrationFile(), "utf8").catch(() => undefined)
+  if (text === undefined) return undefined
+  const value: unknown = JSON.parse(text)
+  if (typeof value !== "object" || value === null) return undefined
+  const record = value as Record<string, unknown>
+  if (typeof record.url !== "string") return undefined
+  if (typeof record.pid !== "number" || !Number.isInteger(record.pid) || record.pid <= 0) return undefined
+  return {
+    id: typeof record.id === "string" ? record.id : undefined,
+    version: typeof record.version === "string" ? record.version : undefined,
+    url: record.url,
+    pid: record.pid,
+    password: typeof record.password === "string" ? record.password : undefined,
+  }
+}
+
+// Read-only lookup: registration file plus health check and version gate.
+// Never spawns; escalation to start() is the caller's policy.
+export async function discover(options: ServiceOptions = {}): Promise<LocalService | undefined> {
+  const registration = await readRegistration(options.file).catch(() => undefined)
+  if (registration === undefined) return undefined
+  if (options.version !== undefined && registration.version !== options.version) return undefined
+  return await probe(registration, options)
+}
+
+async function probe(registration: Registration, options: ServiceOptions): Promise<LocalService | undefined> {
+  const headers = registration.password === undefined ? undefined : basicAuth(registration.password)
+  const healthy = await fetch(new URL("/api/health", registration.url), {
+    headers,
+    signal: AbortSignal.timeout(options.timeout ?? 2_000),
+  })
+    .then((response) => response.ok)
+    .catch(() => false)
+  if (!healthy) return undefined
+  return { registration, transport: { url: registration.url, headers } }
+}
+
+// Health-checked lookup without the version gate: lifecycle operations must be
+// able to see (and replace or stop) a server from a different version.
+async function anyService(options: ServiceOptions): Promise<LocalService | undefined> {
+  const registration = await readRegistration(options.file).catch(() => undefined)
+  if (registration === undefined) return undefined
+  return await probe(registration, options)
+}
+
+function signal(pid: number, name: "SIGTERM" | "SIGKILL" | 0): boolean {
+  try {
+    process.kill(pid, name)
+    return true
+  } catch {
+    return false
+  }
+}
+
+async function awaitStopped(pid: number, timeout: number): Promise<boolean> {
+  const deadline = Date.now() + timeout
+  while (Date.now() < deadline) {
+    if (!signal(pid, 0)) return true
+    await new Promise((resolve) => setTimeout(resolve, 50))
+  }
+  return !signal(pid, 0)
+}
+
+function sameRegistration(left: Registration, right: Registration) {
+  return left.id === right.id && left.version === right.version && left.url === right.url && left.pid === right.pid
+}
+
+async function stopProcess(info: Registration, options: ServiceOptions): Promise<void> {
+  // A stale registration may point at a PID that has since been reused by
+  // another process. Only signal the PID after authenticating the server.
+  const current = await anyService(options)
+  if (current === undefined || !sameRegistration(current.registration, info)) return
+
+  signal(info.pid, "SIGTERM")
+  if (await awaitStopped(info.pid, 5_000)) return
+
+  const latest = await anyService(options)
+  if (latest === undefined || !sameRegistration(latest.registration, info)) return
+  signal(info.pid, "SIGKILL")
+  await awaitStopped(info.pid, 5_000)
+}
+
+export async function stop(options: ServiceOptions = {}): Promise<void> {
+  const existing = await anyService(options)
+  if (existing !== undefined) await stopProcess(existing.registration, options)
+  await rm(options.file ?? defaultRegistrationFile(), { force: true }).catch(() => undefined)
+}
+
+// Idempotent ensure-running: reuses a healthy compatible server, replaces a
+// version-mismatched one, and otherwise spawns the service command detached.
+export async function start(options: ServiceOptions = {}): Promise<Transport> {
+  const compatible = await discover(options)
+  if (compatible !== undefined) return compatible.transport
+  const mismatched = await anyService(options)
+  if (mismatched !== undefined) await stopProcess(mismatched.registration, options).catch(() => undefined)
+
+  const [command, ...args] = options.command ?? ["opencode", "serve", "--service"]
+  if (command === undefined) throw new Error("Missing service command")
+  spawn(command, args, { detached: true, stdio: "ignore" }).unref()
+
+  const deadline = Date.now() + 5_000
+  while (Date.now() < deadline) {
+    const found = await discover(options)
+    if (found !== undefined) return found.transport
+    await new Promise((resolve) => setTimeout(resolve, 50))
+  }
+  throw new Error("Failed to start server")
+}
+
+// Default connection policy for the local service: discover, else start.
+export async function connect(options: ServiceOptions = {}): Promise<Transport> {
+  const found = await discover(options)
+  if (found !== undefined) return found.transport
+  return await start(options)
+}
diff --git a/packages/tui/src/app.tsx b/packages/tui/src/app.tsx
index fa68adb8ad..7c874ddf8d 100644
--- a/packages/tui/src/app.tsx
+++ b/packages/tui/src/app.tsx
@@ -138,7 +138,7 @@ const appBindingCommands = [
 export type TuiInput = {
   client: OpencodeClient
   api: OpenCodeClient
-  reload?: () => Promise<{ client: OpencodeClient; api: OpenCodeClient }>
+  discover?: () => Promise<{ client: OpencodeClient; api: OpenCodeClient }>
   args: Args
   config: TuiConfig.Resolved
   onSnapshot?: () => Promise<string[]>
@@ -301,7 +301,7 @@ export const run = Effect.fn("Tui.run")(function* (input: TuiInput) {
                                   >
                                     <TuiConfigProvider config={input.config}>
                                       <PluginRuntimeProvider value={pluginRuntime}>
-                                        <SDKProvider client={input.client} api={input.api} reload={input.reload}>
+                                        <SDKProvider client={input.client} api={input.api} discover={input.discover}>
                                           <PermissionProvider>
                                             <ProjectProvider>
                                               <SyncProvider>
@@ -374,7 +374,6 @@ function App(props: { onSnapshot?: () => Promise<string[]>; pluginHost: TuiPlugi
   const keymap = useOpencodeKeymap()
   const event = useEvent()
   const sdk = useSDK()
-  const reload = sdk.reload
   const toast = useToast()
   const themeState = useTheme()
   const { theme, mode, setMode, locked, lock, unlock } = themeState
@@ -801,33 +800,6 @@ function App(props: { onSnapshot?: () => Promise<string[]>; pluginHost: TuiPlugi
         },
         category: "System",
       },
-      ...(reload
-        ? [
-            {
-              name: "server.reload",
-              title: "Reload server",
-              slashName: "reload",
-              slashAliases: ["restart"],
-              run: async () => {
-                dialog.clear()
-                toast.show({
-                  variant: "info",
-                  message: "Reloading server...",
-                  duration: 30000,
-                })
-                await reload()
-                  .then(() =>
-                    toast.show({
-                      variant: "success",
-                      message: "Server reloaded",
-                    }),
-                  )
-                  .catch(toast.error)
-              },
-              category: "System",
-            },
-          ]
-        : []),
       {
         name: "theme.switch",
         title: "Switch theme",
diff --git a/packages/tui/src/context/sdk.tsx b/packages/tui/src/context/sdk.tsx
index f8297dd80b..390eb8aa4a 100644
--- a/packages/tui/src/context/sdk.tsx
+++ b/packages/tui/src/context/sdk.tsx
@@ -15,7 +15,7 @@ export const { use: useSDK, provider: SDKProvider } = createSimpleContext({
   init: (props: {
     client: OpencodeClient
     api: OpenCodeClient
-    reload?: () => Promise<{ client: OpencodeClient; api: OpenCodeClient }>
+    discover?: () => Promise<{ client: OpencodeClient; api: OpenCodeClient }>
   }) => {
     const abort = new AbortController()
     let client = props.client
@@ -32,12 +32,10 @@ export const { use: useSDK, provider: SDKProvider } = createSimpleContext({
       connectedOnce: false,
     })
     let stream: AbortController | undefined
-    let pending: Promise<void> | undefined
 
     function start() {
       stream?.abort()
       const controller = new AbortController()
-      const current = client
       let connected!: () => void
       const ready = new Promise<void>((resolve) => {
         connected = resolve
@@ -54,7 +52,7 @@ export const { use: useSDK, provider: SDKProvider } = createSimpleContext({
           )
           controller.signal.addEventListener("abort", cancel, { once: true })
           const error = await (async () => {
-            const response = await current.v2.event.subscribe({
+            const response = await client.v2.event.subscribe({
               signal: connection.signal,
               sseMaxRetryAttempts: 0,
               throwOnError: true,
@@ -86,6 +84,17 @@ export const { use: useSDK, provider: SDKProvider } = createSimpleContext({
             })
           if (abort.signal.aborted || controller.signal.aborted) return
           attempt += 1
+          // Re-resolve the transport before retrying: the server may have
+          // moved (service restarted on a new port) or need starting. Static
+          // transports (--server, standalone) resolve to the same address.
+          if (props.discover) {
+            const next = await props.discover().catch(() => undefined)
+            if (abort.signal.aborted || controller.signal.aborted) return
+            if (next) {
+              client = next.client
+              api = next.api
+            }
+          }
           setConnection({
             status: "connecting",
             attempt,
@@ -97,23 +106,6 @@ export const { use: useSDK, provider: SDKProvider } = createSimpleContext({
       return ready
     }
 
-    const reload = props.reload
-      ? () => {
-          if (pending) return pending
-          pending = Promise.resolve()
-            .then(props.reload)
-            .then(async (next) => {
-              client = next.client
-              api = next.api
-              if (!abort.signal.aborted) await start()
-            })
-            .finally(() => {
-              pending = undefined
-            })
-          return pending
-        }
-      : undefined
-
     onMount(() => void start())
     onCleanup(() => {
       abort.abort()
@@ -146,7 +138,6 @@ export const { use: useSDK, provider: SDKProvider } = createSimpleContext({
           return connection.connectedOnce
         },
       },
-      reload,
     }
   },
 })
diff --git a/packages/tui/test/cli/tui/use-event.test.tsx b/packages/tui/test/cli/tui/use-event.test.tsx
index ccf5be2fcb..dd87100714 100644
--- a/packages/tui/test/cli/tui/use-event.test.tsx
+++ b/packages/tui/test/cli/tui/use-event.test.tsx
@@ -47,7 +47,7 @@ function update(version: string): V2Event {
   }
 }
 
-async function mount(reload?: () => Promise<{ client: OpencodeClient; api: OpenCodeClient }>) {
+async function mount(discover?: () => Promise<{ client: OpencodeClient; api: OpenCodeClient }>) {
   const events = createEventStream()
   const calls = createFetch(undefined, events)
   const seen: V2Event[] = []
@@ -61,7 +61,7 @@ async function mount(reload?: () => Promise<{ client: OpencodeClient; api: OpenC
 
   const app = await testRender(() => (
     <TestTuiContexts>
-      <SDKProvider client={createClient(calls.fetch)} api={createApi(calls.fetch)} reload={reload}>
+      <SDKProvider client={createClient(calls.fetch)} api={createApi(calls.fetch)} discover={discover}>
         <ProjectProvider>
           <Probe
             onReady={async (ctx) => {
@@ -79,7 +79,7 @@ async function mount(reload?: () => Promise<{ client: OpencodeClient; api: OpenC
   ))
 
   await ready
-  return { app, emit: events.emit, project, sdk, seen, workspaces }
+  return { app, events, emit: events.emit, project, sdk, seen, workspaces }
 }
 
 function Probe(props: {
@@ -148,24 +148,25 @@ describe("useEvent", () => {
     }
   })
 
-  test("reloads the host and reconnects the event stream", async () => {
+  test("rediscovers the server after the event stream drops", async () => {
     let calls = 0
-    const events = createEventStream()
-    const replacementCalls = createFetch(undefined, events)
+    const replacementEvents = createEventStream()
+    const replacementCalls = createFetch(undefined, replacementEvents)
     const replacement = { client: createClient(replacementCalls.fetch), api: createApi(replacementCalls.fetch) }
-    const { app, sdk, seen } = await mount(async () => {
+    const { app, events, sdk, seen } = await mount(async () => {
       calls += 1
       return replacement
     })
 
     try {
       await wait(() => sdk.connection.status() === "connected")
-      await sdk.reload?.()
-      await wait(() => sdk.connection.status() === "connected")
-      events.emit(event(vcs("reloaded"), { directory: "/tmp/reloaded" }))
-      await wait(() => seen.some((item) => item.type === "vcs.branch.updated" && item.data.branch === "reloaded"))
+      // Discovery only runs when the stream is down, never while connected.
+      expect(calls).toBe(0)
+      events.disconnect()
+      await wait(() => sdk.connection.status() === "connected" && calls > 0)
+      replacementEvents.emit(event(vcs("rediscovered"), { directory: "/tmp/rediscovered" }))
+      await wait(() => seen.some((item) => item.type === "vcs.branch.updated" && item.data.branch === "rediscovered"))
 
-      expect(calls).toBe(1)
       expect(sdk.client).toBe(replacement.client)
       expect(sdk.api).toBe(replacement.api)
     } finally {
@@ -173,27 +174,24 @@ describe("useEvent", () => {
     }
   })
 
-  test("keeps the current event stream alive while the host reload is pending", async () => {
-    let complete!: (client: { client: OpencodeClient; api: OpenCodeClient }) => void
-    const pending = new Promise<{ client: OpencodeClient; api: OpenCodeClient }>((resolve) => {
-      complete = resolve
+  test("keeps the current client when discovery fails", async () => {
+    let calls = 0
+    const { app, events, sdk, seen } = await mount(async () => {
+      calls += 1
+      throw new Error("no server")
     })
-    const replacementEvents = createEventStream()
-    const replacementCalls = createFetch(undefined, replacementEvents)
-    const replacement = { client: createClient(replacementCalls.fetch), api: createApi(replacementCalls.fetch) }
-    const { app, emit, sdk, seen } = await mount(() => pending)
 
     try {
       await wait(() => sdk.connection.status() === "connected")
-      const reload = sdk.reload?.()
-      emit(event(vcs("during-reload"), { directory: "/tmp/reload" }))
-      await wait(() => seen.some((item) => item.type === "vcs.branch.updated" && item.data.branch === "during-reload"))
+      const original = sdk.client
+      events.disconnect()
+      // Discovery rejects; the loop retries against the last known transport,
+      // which succeeds once the fixture accepts the reconnect.
+      await wait(() => calls > 0 && sdk.connection.status() === "connected")
+      events.emit(event(vcs("recovered"), { directory: "/tmp/recovered" }))
+      await wait(() => seen.some((item) => item.type === "vcs.branch.updated" && item.data.branch === "recovered"))
 
-      expect(sdk.connection.status()).toBe("connected")
-      complete(replacement)
-      await reload
-      expect(sdk.client).toBe(replacement.client)
-      expect(sdk.api).toBe(replacement.api)
+      expect(sdk.client).toBe(original)
     } finally {
       app.renderer.destroy()
     }