fix(bonjour): default mdns host to system hostname

CHANGELOG.md

@@ -22,6 +22,7 @@ Docs: https://docs.openclaw.ai
 
 - Channels/setup: treat bundled channel plugins as already bundled during `channels add` and onboarding, enabling them without writing redundant `plugins.load.paths` entries or path install records. Fixes #72740. Thanks @iCodePoet.
 - WhatsApp: honor gateway `HTTPS_PROXY` / `HTTP_PROXY` env vars for QR-login WebSocket connections, while respecting `NO_PROXY`, so proxied networks no longer fall back to direct `mmg.whatsapp.net` connections that time out with 408. Fixes #72547; supersedes #72692. Thanks @mebusw and @SymbolStar.
+- Bonjour: default mDNS advertisements to the system hostname when it is DNS-safe, avoiding `openclaw.local` probing conflicts and Gateway restart loops on hosts such as `Lobster` or `ubuntu`. Fixes #72355 and #72689; supersedes #72694. Thanks @mscheuerlein-bot, @gcusms, @moyuwuhen601, @pavan987, @zml-0912, @hhq365, and @SymbolStar.
 - Agents/OpenAI-compatible: retry replay-safe empty `stop` turns once for `openai-completions` endpoints, so transient empty local backend responses no longer surface as “Agent couldn't generate a response” when a continuation succeeds. Fixes #72751. Thanks @moooV252.
 - Git hooks: skip ignored staged paths when formatting and restaging pre-commit files, so merge commits no longer abort when `.gitignore` newly ignores staged merged content. Fixes #72744. Thanks @100yenadmin.
 - Memory-core/dreaming: add a supported `dreaming.model` knob for Dream Diary narrative subagents, wired through phase config and the existing plugin subagent model-override trust gate. Refs #65963. Thanks @esqandil and @mjamiv.

docs/gateway/bonjour.md

@@ -141,6 +141,12 @@ The Gateway writes a rolling log file (printed on startup as
 - `bonjour: watchdog detected non-announced service ...`
 - `bonjour: disabling advertiser after ... failed restarts ...`
 
+Bonjour uses the system hostname for the advertised `.local` host when it is a
+valid DNS label. If the system hostname contains spaces, underscores, or another
+invalid DNS-label character, OpenClaw falls back to `openclaw.local`. Set
+`OPENCLAW_MDNS_HOSTNAME=<name>` before starting the Gateway when you need an
+explicit host label.
+
 ## Debugging on iOS node
 
 The iOS node uses `NWBrowser` to discover `_openclaw-gw._tcp`.

docs/gateway/configuration-reference.md

@@ -649,7 +649,7 @@ Validation and safety notes:
 
 - `minimal` (default): omit `cliPath` + `sshPort` from TXT records.
 - `full`: include `cliPath` + `sshPort`.
-- Hostname defaults to `openclaw`. Override with `OPENCLAW_MDNS_HOSTNAME`.
+- Hostname defaults to the system hostname when it is a valid DNS label, falling back to `openclaw`. Override with `OPENCLAW_MDNS_HOSTNAME`.
 
 ### Wide-area (DNS-SD)
 

extensions/bonjour/src/advertiser.test.ts

@@ -704,11 +704,57 @@ describe("gateway bonjour advertiser", () => {
     });
 
     const [gatewayCall] = createService.mock.calls as Array<[ServiceCall]>;
-    expect(gatewayCall?.[0]?.name).toBe("openclaw (OpenClaw)");
+    expect(gatewayCall?.[0]?.name).toBe("Mac (OpenClaw)");
     expect(gatewayCall?.[0]?.domain).toBe("local");
+    expect(gatewayCall?.[0]?.hostname).toBe("Mac");
+    expect((gatewayCall?.[0]?.txt as Record<string, string>)?.lanHost).toBe("Mac.local");
+
+    await started.stop();
+  });
+
+  it("falls back to openclaw when system hostname is invalid for DNS", async () => {
+    // Allow advertiser to run in unit tests.
+    delete process.env.VITEST;
+    process.env.NODE_ENV = "development";
+    delete process.env.OPENCLAW_MDNS_HOSTNAME;
+    vi.spyOn(os, "hostname").mockReturnValue("My_Lobster Host");
+
+    const destroy = vi.fn().mockResolvedValue(undefined);
+    const advertise = vi.fn().mockResolvedValue(undefined);
+    mockCiaoService({ advertise, destroy });
+
+    const started = await startAdvertiser({
+      gatewayPort: 18789,
+      sshPort: 2222,
+    });
+
+    const [gatewayCall] = createService.mock.calls as Array<[ServiceCall]>;
     expect(gatewayCall?.[0]?.hostname).toBe("openclaw");
     expect((gatewayCall?.[0]?.txt as Record<string, string>)?.lanHost).toBe("openclaw.local");
 
     await started.stop();
   });
+
+  it("uses system hostname when OPENCLAW_MDNS_HOSTNAME is unset", async () => {
+    // Allow advertiser to run in unit tests.
+    delete process.env.VITEST;
+    process.env.NODE_ENV = "development";
+    delete process.env.OPENCLAW_MDNS_HOSTNAME;
+    vi.spyOn(os, "hostname").mockReturnValue("Lobster");
+
+    const destroy = vi.fn().mockResolvedValue(undefined);
+    const advertise = vi.fn().mockResolvedValue(undefined);
+    mockCiaoService({ advertise, destroy });
+
+    const started = await startAdvertiser({
+      gatewayPort: 18789,
+      sshPort: 2222,
+    });
+
+    const [gatewayCall] = createService.mock.calls as Array<[ServiceCall]>;
+    expect(gatewayCall?.[0]?.hostname).toBe("Lobster");
+    expect((gatewayCall?.[0]?.txt as Record<string, string>)?.lanHost).toBe("Lobster.local");
+
+    await started.stop();
+  });
 });

extensions/bonjour/src/advertiser.ts

@@ -1,6 +1,7 @@
 import type { ChildProcess } from "node:child_process";
 import fs from "node:fs";
 import { createRequire } from "node:module";
+import os from "node:os";
 import type { PluginLogger } from "openclaw/plugin-sdk/plugin-entry";
 import { isTruthyEnvValue } from "openclaw/plugin-sdk/runtime-env";
 import { classifyCiaoProcessError, type CiaoProcessErrorClassification } from "./ciao.js";
@@ -160,6 +161,28 @@ function isDisabledByEnv() {
   return false;
 }
 
+function resolveSystemMdnsHostname(): string | null {
+  let raw: string;
+  try {
+    raw = os.hostname();
+  } catch {
+    return null;
+  }
+  const trimmed = raw.trim();
+  if (!trimmed) {
+    return null;
+  }
+  const firstLabel =
+    trimmed
+      .replace(/\.local$/i, "")
+      .split(".")[0]
+      ?.trim() ?? "";
+  if (!/^[A-Za-z0-9](?:[A-Za-z0-9-]{0,61}[A-Za-z0-9])?$/.test(firstLabel)) {
+    return null;
+  }
+  return firstLabel;
+}
+
 function safeServiceName(name: string) {
   const trimmed = name.trim();
   return trimmed.length > 0 ? trimmed : "OpenClaw";
@@ -328,7 +351,8 @@ export async function startGatewayBonjourAdvertiser(
     cleanupUnhandledRejection = deps.registerUnhandledRejectionHandler?.(handleCiaoProcessError);
     cleanupUncaughtException = deps.registerUncaughtExceptionHandler?.(handleCiaoProcessError);
 
-    const hostnameRaw = process.env.OPENCLAW_MDNS_HOSTNAME?.trim() || "openclaw";
+    const hostnameRaw =
+      process.env.OPENCLAW_MDNS_HOSTNAME?.trim() || resolveSystemMdnsHostname() || "openclaw";
     const hostname =
       hostnameRaw
         .replace(/\.local$/i, "")