feat(tui): add --no-server flag for headless instance bootstrap

Adds a --no-server flag to opencode tui that runs only the
HTTP server without launching the TUI, useful for headless
environments and remote attach workflows.

Author: caretak3r

packages/opencode/src/cli/cmd/tui/thread.ts

@@ -23,6 +23,8 @@ import {
 } from "@opencode-ai/core/util/opencode-process"
 import { validateSession } from "./validate-session"
 import { Provider } from "@/provider/provider"
+import { bootstrap } from "@/cli/bootstrap"
+import { Server } from "@/server/server"
 
 declare global {
   const OPENCODE_WORKER_PATH: string
@@ -117,6 +119,11 @@ export const TuiThreadCommand = cmd({
       .option("variant", {
         type: "string",
         describe: "model variant (provider-specific reasoning effort, e.g., high, max, minimal)",
+      })
+      .option("no-server", {
+        type: "boolean",
+        default: false,
+        describe: "run headless server without TUI (full instance bootstrap)",
       }),
   handler: async (args) => {
     // Keep ENABLE_PROCESSED_INPUT cleared even if other code flips it.
@@ -136,17 +143,31 @@ export const TuiThreadCommand = cmd({
       // Resolve relative --project paths from PWD, then use the real cwd after
       // chdir so the thread and worker share the same directory key.
       const next = resolveThreadDirectory(args.project)
-      const file = await target()
       try {
         process.chdir(next)
       } catch {
         UI.error("Failed to change directory to " + next)
         return
       }
       const cwd = Filesystem.resolve(process.cwd())
+
+      if (args.noServer) {
+        const network = resolveNetworkOptionsNoConfig(args)
+        await bootstrap(cwd, async () => {
+          const server = await Server.listen(network)
+          Log.Default.info("opencode server (headless) listening", {
+            url: server.url.toString(),
+          })
+          await new Promise(() => {})
+          await server.stop()
+        })
+        return
+      }
+
       const pick = await Provider.resolveSelection(args.model, args.variant)
       const model = pick.model
       const variant = pick.variant
+      const file = await target()
       const env = sanitizedProcessEnv({
         [OPENCODE_PROCESS_ROLE]: "worker",
         [OPENCODE_RUN_ID]: ensureRunID(),

packages/opencode/test/cli/tui/thread.test.ts

@@ -97,6 +97,8 @@ describe("tui thread", () => {
       "mdns-domain": "opencode.local",
       mdnsDomain: "opencode.local",
       cors: [],
+      "no-server": false,
+      noServer: false,
     }
     return TuiThreadCommand.handler(args)
   }