fix(cli): restart stale clients after updates

packages/cli/bin/opencode2.cjs

@@ -6,8 +6,9 @@ const path = require("path")
 const os = require("os")
 
 const forwardedSignals = ["SIGINT", "SIGTERM", "SIGHUP"]
+const restartExitCode = 75
 
-function run(target) {
+function run(target, restarted = false) {
   const child = childProcess.spawn(target, process.argv.slice(2), { stdio: "inherit" })
   child.on("error", (error) => {
     console.error(error.message)
@@ -25,6 +26,7 @@ function run(target) {
   child.on("exit", (code, signal) => {
     for (const forwardedSignal of forwardedSignals) process.removeListener(forwardedSignal, forwarders[forwardedSignal])
     if (signal) return process.kill(process.pid, signal)
+    if (code === restartExitCode && !restarted) return run(target, true)
     process.exit(typeof code === "number" ? code : 0)
   })
 }

packages/cli/src/commands/handlers/default.ts

@@ -8,6 +8,8 @@ import { ServiceConfig } from "../../services/service-config"
 import { Standalone } from "../../services/standalone"
 import { Updater } from "../../services/updater"
 
+const restartExitCode = 75
+
 export default Runtime.handler(Commands, (input) =>
   Effect.gen(function* () {
     const directory = Option.getOrUndefined(input.directory)
@@ -22,9 +24,7 @@ export default Runtime.handler(Commands, (input) =>
         const password = yield* Env.password
         const explicit = {
           url: server,
-          headers: password
-            ? { authorization: "Basic " + btoa("opencode:" + Redacted.value(password)) }
-            : undefined,
+          headers: password ? { authorization: "Basic " + btoa("opencode:" + Redacted.value(password)) } : undefined,
         } satisfies Service.Transport
         // Fail loudly before entering the TUI: an explicit server that is
         // unreachable or rejects auth should not present as reconnect churn.
@@ -60,7 +60,7 @@ export default Runtime.handler(Commands, (input) =>
             Effect.gen(function* () {
               const found = yield* Service.discover(serviceOptions)
               return found ?? (yield* Service.start(serviceOptions))
-            }).pipe(Effect.provide(NodeFileSystem.layer)),
+            }).pipe(Effect.catchIf(versionMismatch, restart), Effect.provide(NodeFileSystem.layer)),
           )
       : () => Promise.resolve(transport)
     // Restart the managed service in place; start() resolves once the
@@ -76,11 +76,36 @@ export default Runtime.handler(Commands, (input) =>
             }).pipe(Effect.provide(NodeFileSystem.layer)),
           )
       : undefined
-    yield* runTui(
+    return yield* runTui(
       transport,
       { continue: input.continue, sessionID: Option.getOrUndefined(input.session) },
       discover,
       reload,
+      () => {
+        process.exitCode = restartExitCode
+      },
     )
-  }),
+  }).pipe(
+    Effect.catchIf(versionMismatch, (error) =>
+      restart(error).pipe(
+        Effect.tap(() =>
+          Effect.sync(() => {
+            process.exitCode = restartExitCode
+          }),
+        ),
+        Effect.asVoid,
+      ),
+    ),
+  ),
 )
+
+function restart(error: Service.VersionMismatchError) {
+  return Effect.logInfo("restarting stale client", {
+    clientVersion: error.clientVersion,
+    serverVersion: error.serverVersion,
+  }).pipe(Effect.as({ restart: true as const }))
+}
+
+function versionMismatch(error: unknown): error is Service.VersionMismatchError {
+  return error instanceof Service.VersionMismatchError
+}

packages/cli/src/index.ts

@@ -56,6 +56,6 @@ Effect.logInfo("cli starting", {
   Effect.provide(LoggingLayer),
   Effect.provide(NodeServices.layer),
   Effect.scoped,
-  Effect.tap(() => Effect.sync(() => process.exit(0))),
+  Effect.tap(() => Effect.sync(() => process.exit(process.exitCode ?? 0))),
   NodeRuntime.runMain,
 )

packages/cli/src/services/service-config.ts

@@ -4,6 +4,7 @@ import { Service } from "@opencode-ai/client/effect"
 import { Effect, FileSystem, Schema } from "effect"
 import { randomBytes } from "crypto"
 import path from "path"
+import semver from "semver"
 
 // The CLI's service configuration file, plus the Service.Options binding that
 // points the client package's service operations at this CLI: which
@@ -45,10 +46,21 @@ export const options = Effect.fnUntraced(function* () {
   return {
     file,
     version: InstallationVersion,
+    canReplace: (version: string | undefined) => canReplaceVersion(version, InstallationVersion),
     command: [process.execPath, ...(entrypoint ? [entrypoint] : []), "serve", "--service"],
   }
 })
 
+export function canReplaceVersion(serverVersion: string | undefined, clientVersion: string) {
+  if (serverVersion === undefined) return true
+  // Preview versions end in `<channel>-<build>[.<attempt>]`. Convert the build
+  // to a numeric semver identifier so next-15000 sorts after next-9999.
+  const server = serverVersion.replace(/-(\d+)(?=(?:\.\d+)?$)/, ".$1")
+  const client = clientVersion.replace(/-(\d+)(?=(?:\.\d+)?$)/, ".$1")
+  if (!semver.valid(server) || !semver.valid(client)) return true
+  return semver.lt(server, client)
+}
+
 export const read = Effect.fn("cli.service-config.read")(function* () {
   const { fs, configFile } = yield* env
   return yield* fs.readFileString(configFile).pipe(

packages/cli/src/tui.ts

@@ -12,8 +12,9 @@ import type { Args } from "@opencode-ai/tui/context/args"
 export function runTui(
   transport: Service.Transport,
   args: Args,
-  discover?: () => Promise<Service.Transport>,
+  discover?: () => Promise<Service.Transport | { restart: true }>,
   reload?: () => Promise<void>,
+  restart?: () => void,
 ) {
   const config = TuiConfig.resolve({}, { terminalSuspend: false })
   let disposeSlots: (() => void) | undefined
@@ -32,12 +33,14 @@ export function runTui(
       discover: discover
         ? async () => {
             const next = await discover()
+            if ("restart" in next) return next
             return {
               client: createOpencodeClient({ baseUrl: next.url, headers: next.headers, directory }),
               api: OpenCode.make({ baseUrl: next.url, headers: next.headers }),
             }
           }
         : undefined,
+      restart,
       reload,
       args,
       config,

packages/cli/test/fixture/restart-child.ts

@@ -0,0 +1,6 @@
+const stateFile = process.argv[2]
+const exit = Number(process.argv[3])
+const count = (await Bun.file(stateFile).exists()) ? Number(await Bun.file(stateFile).text()) : 0
+
+await Bun.write(stateFile, String(count + 1))
+process.exit(exit || (count === 0 ? 75 : 0))

packages/cli/test/launcher.test.ts

@@ -0,0 +1,43 @@
+import { expect, test } from "bun:test"
+import fs from "node:fs/promises"
+import os from "node:os"
+import path from "node:path"
+
+const launcher = path.join(import.meta.dir, "../bin/opencode2.cjs")
+const fixture = path.join(import.meta.dir, "fixture/restart-child.ts")
+
+test("restarts the installed binary once with the original arguments", async () => {
+  const root = await fs.mkdtemp(path.join(os.tmpdir(), "opencode-launcher-"))
+  const state = path.join(root, "count")
+
+  try {
+    const child = Bun.spawn([process.execPath, launcher, fixture, state, "0"], {
+      env: { ...process.env, OPENCODE_BIN_PATH: process.execPath },
+      stdout: "pipe",
+      stderr: "pipe",
+    })
+
+    expect(await child.exited).toBe(0)
+    expect(await Bun.file(state).text()).toBe("2")
+  } finally {
+    await fs.rm(root, { recursive: true, force: true })
+  }
+})
+
+test("bounds automatic restarts", async () => {
+  const root = await fs.mkdtemp(path.join(os.tmpdir(), "opencode-launcher-"))
+  const state = path.join(root, "count")
+
+  try {
+    const child = Bun.spawn([process.execPath, launcher, fixture, state, "75"], {
+      env: { ...process.env, OPENCODE_BIN_PATH: process.execPath },
+      stdout: "pipe",
+      stderr: "pipe",
+    })
+
+    expect(await child.exited).toBe(75)
+    expect(await Bun.file(state).text()).toBe("2")
+  } finally {
+    await fs.rm(root, { recursive: true, force: true })
+  }
+})

packages/cli/test/service.test.ts

@@ -7,6 +7,18 @@ import os from "node:os"
 import path from "node:path"
 import { ServiceConfig } from "../src/services/service-config"
 
+test("only replaces older semantic versions", () => {
+  expect(ServiceConfig.canReplaceVersion("1.0.0", "2.0.0")).toBe(true)
+  expect(ServiceConfig.canReplaceVersion("2.0.0", "1.0.0")).toBe(false)
+  expect(ServiceConfig.canReplaceVersion("1.0.0", "1.0.0")).toBe(false)
+  expect(ServiceConfig.canReplaceVersion("0.0.0-next-9999", "0.0.0-next-15000")).toBe(true)
+  expect(ServiceConfig.canReplaceVersion("0.0.0-next-15000", "0.0.0-next-9999")).toBe(false)
+  expect(ServiceConfig.canReplaceVersion("0.0.0-next-15000.1", "0.0.0-next-15000.2")).toBe(true)
+  expect(ServiceConfig.canReplaceVersion("0.0.0-next-15000.10", "0.0.0-next-15000.9")).toBe(false)
+  expect(ServiceConfig.canReplaceVersion("0.0.0-next-15000.10", "0.0.0-next-15000.10")).toBe(false)
+  expect(ServiceConfig.canReplaceVersion(undefined, "1.0.0")).toBe(true)
+})
+
 test("local channel stores service config with the local service filename", async () => {
   const root = await fs.mkdtemp(path.join(os.tmpdir(), "opencode-service-"))
   try {

packages/client/src/effect/service.ts

@@ -1,4 +1,4 @@
-import { Effect, FileSystem, Option, Schedule, Schema } from "effect"
+import { Data, Effect, FileSystem, Option, Schedule, Schema } from "effect"
 import { spawn } from "node:child_process"
 import { homedir } from "node:os"
 import { join } from "node:path"
@@ -23,6 +23,9 @@ export type Options = {
   // When set, discovery only returns a server reporting this exact version,
   // and start() replaces a healthy server whose version differs.
   readonly version?: string
+  // Decides whether start() may terminate a healthy version-mismatched server.
+  // Defaults to true for callers that do not need directional version handling.
+  readonly canReplace?: (version: string | undefined) => boolean
   // Argv used to spawn the service. Defaults to ["opencode", "serve",
   // "--service"] resolved from PATH.
   readonly command?: ReadonlyArray<string>
@@ -44,7 +47,11 @@ export const start = Effect.fn("service.start")(function* (options: Options = {}
   const compatible = yield* discover(options)
   if (compatible !== undefined) return compatible
   const mismatched = yield* find(options)
-  if (mismatched !== undefined) yield* kill(mismatched.info, options).pipe(Effect.ignore)
+  if (mismatched !== undefined) {
+    const error = replacementError(mismatched.info, options)
+    if (error) return yield* Effect.fail(error)
+    yield* kill(mismatched.info, options).pipe(Effect.ignore)
+  }
 
   const [command, ...args] = options.command ?? ["opencode", "serve", "--service"]
   if (command === undefined) return yield* Effect.fail(new Error("Missing service command"))
@@ -67,8 +74,12 @@ export const start = Effect.fn("service.start")(function* (options: Options = {}
 export const stop = Effect.fn("service.stop")(function* (options: Options = {}) {
   const fs = yield* FileSystem.FileSystem
   const existing = yield* find(options)
-  if (existing !== undefined) yield* kill(existing.info, options)
-  yield* fs.remove(options.file ?? fallback()).pipe(Effect.ignore)
+  if (existing !== undefined) {
+    const error = replacementError(existing.info, options)
+    if (error) return yield* Effect.fail(error)
+    yield* kill(existing.info, options)
+  }
+  return yield* fs.remove(options.file ?? fallback()).pipe(Effect.ignore)
 })
 
 function fallback() {
@@ -89,6 +100,22 @@ export const Info = Schema.Struct({
 })
 export type Info = typeof Info.Type
 
+export class VersionMismatchError extends Data.TaggedError("ServiceVersionMismatchError")<{
+  readonly clientVersion: string | undefined
+  readonly serverVersion: string | undefined
+  readonly message: string
+}> {}
+
+function replacementError(info: Info, options: Options): VersionMismatchError | undefined {
+  if (options.version === undefined || info.version === options.version || options.canReplace?.(info.version) !== false)
+    return undefined
+  return new VersionMismatchError({
+    clientVersion: options.version,
+    serverVersion: info.version,
+    message: `Client version ${options.version} cannot replace server version ${info.version ?? "unknown"}`,
+  })
+}
+
 const decode = Schema.decodeUnknownEffect(Schema.fromJsonString(Info))
 
 // A missing or corrupt file means no valid info; callers treat both

packages/client/test/service.test.ts

@@ -0,0 +1,49 @@
+import { NodeFileSystem } from "@effect/platform-node"
+import { afterEach, expect, test } from "bun:test"
+import { Effect } from "effect"
+import fs from "node:fs/promises"
+import os from "node:os"
+import path from "node:path"
+import { Service } from "../src/effect/index"
+
+const cleanup: Array<() => void | Promise<void>> = []
+
+afterEach(async () => {
+  await Promise.all(cleanup.splice(0).map(async (run) => await run()))
+})
+
+test("does not start or stop a healthy service rejected by the version policy", async () => {
+  const root = await fs.mkdtemp(path.join(os.tmpdir(), "opencode-client-service-"))
+  const child = Bun.spawn([process.execPath, "-e", "await new Promise(() => {})"])
+  const server = Bun.serve({ port: 0, fetch: () => Response.json({ healthy: true }) })
+  const file = path.join(root, "service.json")
+  cleanup.push(
+    () => child.kill(),
+    () => server.stop(true),
+    () => fs.rm(root, { recursive: true, force: true }),
+  )
+  await Bun.write(file, JSON.stringify({ id: "newer", version: "2.0.0", url: server.url.toString(), pid: child.pid }))
+
+  const options = {
+    file,
+    version: "1.0.0",
+    canReplace: () => false,
+    command: [process.execPath, "-e", "throw new Error('should not spawn')"],
+  }
+  const startError = await Service.start(options).pipe(
+    Effect.flip,
+    Effect.provide(NodeFileSystem.layer),
+    Effect.runPromise,
+  )
+  const stopError = await Service.stop(options).pipe(
+    Effect.flip,
+    Effect.provide(NodeFileSystem.layer),
+    Effect.runPromise,
+  )
+
+  expect(startError).toBeInstanceOf(Service.VersionMismatchError)
+  expect(startError).toMatchObject({ clientVersion: "1.0.0", serverVersion: "2.0.0" })
+  expect(stopError).toBeInstanceOf(Service.VersionMismatchError)
+  expect(process.kill(child.pid, 0)).toBe(true)
+  expect(await Bun.file(file).exists()).toBe(true)
+})

packages/tui/src/app.tsx

@@ -30,7 +30,7 @@ import { PluginRouteMissing } from "./component/plugin-route-missing"
 import { ProjectProvider, useProject } from "./context/project"
 import { EditorContextProvider } from "./context/editor"
 import { useEvent } from "./context/event"
-import { SDKProvider, useSDK } from "./context/sdk"
+import { SDKProvider, useSDK, type SDKDiscovery } from "./context/sdk"
 import { StartupLoading } from "./component/startup-loading"
 import { Reconnecting } from "./component/reconnecting"
 import { SyncProvider, useSync } from "./context/sync"
@@ -138,7 +138,8 @@ const appBindingCommands = [
 export type TuiInput = {
   client: OpencodeClient
   api: OpenCodeClient
-  discover?: () => Promise<{ client: OpencodeClient; api: OpenCodeClient }>
+  discover?: () => Promise<SDKDiscovery>
+  restart?: () => void
   reload?: () => Promise<void>
   args: Args
   config: TuiConfig.Resolved
@@ -302,7 +303,16 @@ export const run = Effect.fn("Tui.run")(function* (input: TuiInput) {
                                   >
                                     <TuiConfigProvider config={input.config}>
                                       <PluginRuntimeProvider value={pluginRuntime}>
-                                        <SDKProvider client={input.client} api={input.api} discover={input.discover} reload={input.reload}>
+                                        <SDKProvider
+                                          client={input.client}
+                                          api={input.api}
+                                          discover={input.discover}
+                                          restart={() => {
+                                            input.restart?.()
+                                            destroyRenderer(renderer)
+                                          }}
+                                          reload={input.reload}
+                                        >
                                           <PermissionProvider>
                                             <ProjectProvider>
                                               <SyncProvider>
@@ -812,8 +822,7 @@ function App(props: { onSnapshot?: () => Promise<string[]>; pluginHost: TuiPlugi
                 toast.show({ variant: "info", message: "Reloading server...", duration: 30000 })
                 // reload resolves once the replacement service is healthy; the
                 // event stream reattaches through the reconnect loop.
-                await sdk
-                  .reload!()
+                await sdk.reload!()
                   .then(() => toast.show({ variant: "success", message: "Server reloaded" }))
                   .catch(toast.error)
               },