diff --git a/scripts/src/hwlab-node-impl.ts b/scripts/src/hwlab-node-impl.ts
index 4c2e6256..0f0bf2f3 100644
--- a/scripts/src/hwlab-node-impl.ts
+++ b/scripts/src/hwlab-node-impl.ts
@@ -8,7 +8,7 @@ import { runCommand, type CommandResult } from "./command";
 import { startJob } from "./jobs";
 import { classifySshTcpPoolFailure } from "./ssh";
 import { HWLAB_NODE_CONTROL_PLANE_CONFIG_PATH, hwlabNodeControlPlaneInfraHelp, runHwlabNodeControlPlaneInfra } from "./hwlab-node-control-plane";
-import { hwlabRuntimeLaneConfigPath, hwlabRuntimeLaneSpec, hwlabRuntimeLaneSpecForNode, isHwlabRuntimeLane, type HwlabRuntimeLane, type HwlabRuntimeLaneSpec, type HwlabRuntimeObservabilityRecordingRuleSpec, type HwlabRuntimeObservabilitySpec, type HwlabRuntimeObservabilityWarningAlertSpec, type HwlabRuntimePublicExposureSpec } from "./hwlab-node-lanes";
+import { hwlabRuntimeLaneConfigPath, hwlabRuntimeLaneIds, hwlabRuntimeLaneSpec, hwlabRuntimeLaneSpecForNode, hwlabRuntimeNodeIds, isHwlabRuntimeLane, type HwlabRuntimeLane, type HwlabRuntimeLaneSpec, type HwlabRuntimeObservabilityRecordingRuleSpec, type HwlabRuntimeObservabilitySpec, type HwlabRuntimeObservabilityWarningAlertSpec, type HwlabRuntimePublicExposureSpec } from "./hwlab-node-lanes";
 import { nodeWebProbeScriptRunnerSource } from "./hwlab-node-web-probe-runner-source";
 import { nodeWebObserveAnalyzerSource, nodeWebObserveRunnerSource } from "./hwlab-node-web-observe-runner-source";
 import { hwlabNodeHelp, hwlabNodeObservabilityHelp, hwlabNodeWebProbeHelp } from "./hwlab-node-help";
@@ -5860,11 +5860,19 @@ function parseNodeWebProbeOptions(args: string[]): NodeWebProbeOptions {
   if (actionRaw !== "run" && actionRaw !== "script" && actionRaw !== "observe") throw new Error("web-probe usage: run|script|observe --node NODE --lane vNN [--url URL]");
   if (actionRaw === "observe") {
     const normalized = normalizeNodeWebProbeObserveArgs(args.slice(1));
-    const indexed = normalized.id === null ? null : readWebObserveIndexEntry(normalized.id);
-    const node = optionValue(args, "--node") ?? indexed?.node;
-    const lane = optionValue(args, "--lane") ?? indexed?.lane;
+    const explicitNode = optionValue(args, "--node");
+    const explicitLane = optionValue(args, "--lane");
+    const requestedId = normalized.id ?? optionValue(normalized.args, "--job-id") ?? null;
+    const indexed = requestedId === null
+      ? null
+      : readWebObserveIndexEntry(requestedId) ?? (explicitNode === undefined || explicitLane === undefined ? discoverWebObserveIndexEntry(requestedId) : null);
+    const node = explicitNode ?? indexed?.node;
+    const lane = explicitLane ?? indexed?.lane;
     if (node === undefined || lane === undefined) {
-      throw new Error("web-probe observe requires --node/--lane for start, or a known observer id from observe start for status|command|stop|collect|analyze");
+      if (requestedId !== null) {
+        throw new Error(`web-probe observe observer-id-unknown: ${requestedId}; run observe start first, or pass --node/--lane with --job-id/--state-dir to re-index this observer`);
+      }
+      throw new Error("web-probe observe node-lane-required-for-start: observe start requires --node/--lane; status|command|stop|collect|analyze should pass an observer id");
     }
     assertNodeId(node);
     assertLane(lane);
@@ -6650,6 +6658,114 @@ function readWebObserveIndexEntry(id: string): WebObserveIndexEntry | null {
   return readWebObserveIndex()[id] ?? null;
 }
 
+function discoverWebObserveIndexEntry(id: string): WebObserveIndexEntry | null {
+  const matches: WebObserveIndexEntry[] = [];
+  const errors: string[] = [];
+  for (const lane of hwlabRuntimeLaneIds()) {
+    for (const node of hwlabRuntimeNodeIds()) {
+      let spec: HwlabRuntimeLaneSpec;
+      try {
+        spec = hwlabRuntimeLaneSpecForNode(lane, node);
+      } catch {
+        continue;
+      }
+      try {
+        const entry = discoverWebObserveIndexEntryOnTarget(id, node, lane, spec);
+        if (entry !== null) matches.push(entry);
+      } catch (error) {
+        const message = error instanceof Error ? error.message : String(error);
+        errors.push(`${node}/${lane}: ${message.slice(0, 240)}`);
+      }
+    }
+  }
+  if (matches.length > 1) {
+    const candidates = matches.map((entry) => `${entry.node}/${entry.lane}:${entry.stateDir}`).join(", ");
+    throw new Error(`web-probe observe observer-id-ambiguous: ${id}; candidates=${candidates}`);
+  }
+  if (matches.length === 0) {
+    if (errors.length > 0) {
+      throw new Error(`web-probe observe observer-id-unknown: ${id}; discoveryErrors=${errors.join(" | ")}`);
+    }
+    return null;
+  }
+  upsertWebObserveIndexEntry(matches[0]!);
+  return matches[0]!;
+}
+
+function discoverWebObserveIndexEntryOnTarget(id: string, node: string, lane: HwlabRuntimeLane, spec: HwlabRuntimeLaneSpec): WebObserveIndexEntry | null {
+  const observeRoot = `.state/web-observe/${safeWebObserveSegment(node)}/${safeWebObserveSegment(lane)}`;
+  const script = [
+    "set -eu",
+    `observe_root=${shellQuote(observeRoot)}`,
+    `job_id=${shellQuote(id)}`,
+    "node - \"$observe_root\" \"$job_id\" <<'NODE'",
+    "const fs = require('fs');",
+    "const path = require('path');",
+    "const [root, jobId] = process.argv.slice(2);",
+    "const matches = [];",
+    "function readJson(file) { try { return JSON.parse(fs.readFileSync(file, 'utf8')); } catch { return null; } }",
+    "function walk(dir, depth) {",
+    "  if (depth > 10 || matches.length > 1) return;",
+    "  let entries = [];",
+    "  try { entries = fs.readdirSync(dir, { withFileTypes: true }); } catch { return; }",
+    "  for (const entry of entries) {",
+    "    if (!entry.isDirectory()) continue;",
+    "    const full = path.join(dir, entry.name);",
+    "    if (entry.name.endsWith('_' + jobId)) matches.push(full);",
+    "    else walk(full, depth + 1);",
+    "    if (matches.length > 1) return;",
+    "  }",
+    "}",
+    "walk(root, 0);",
+    "if (matches.length === 0) { console.log(JSON.stringify({ ok: true, found: false, root, jobId })); process.exit(0); }",
+    "if (matches.length > 1) { console.log(JSON.stringify({ ok: false, found: true, ambiguous: true, root, jobId, matches })); process.exit(3); }",
+    "const stateDir = matches[0];",
+    "const manifest = readJson(path.join(stateDir, 'manifest.json')) || {};",
+    "const heartbeat = readJson(path.join(stateDir, 'heartbeat.json')) || {};",
+    "let pid = null;",
+    "try { const raw = fs.readFileSync(path.join(stateDir, 'pid'), 'utf8').trim(); const value = Number(raw); if (Number.isFinite(value)) pid = value; } catch {}",
+    "console.log(JSON.stringify({",
+    "  ok: true,",
+    "  found: true,",
+    "  ambiguous: false,",
+    "  entry: {",
+    "    id: jobId,",
+    "    stateDir,",
+    "    url: typeof manifest.baseUrl === 'string' ? manifest.baseUrl : '',",
+    "    targetPath: typeof manifest.targetPath === 'string' ? manifest.targetPath : '',",
+    "    status: typeof manifest.status === 'string' ? manifest.status : null,",
+    "    pid,",
+    "    startedAt: typeof manifest.startedAt === 'string' ? manifest.startedAt : null,",
+    "    updatedAt: typeof heartbeat.updatedAt === 'string' ? heartbeat.updatedAt : new Date().toISOString()",
+    "  }",
+    "}));",
+    "NODE",
+  ].join("\n");
+  const result = runTransWorkspaceStdinScript(node, spec.workspace, script, 55);
+  const payload = parseJsonObject(result.stdout);
+  if (result.exitCode !== 0 || result.timedOut || payload?.ok !== true) {
+    const reason = result.timedOut ? "timeout" : payload?.ambiguous === true ? "ambiguous" : `exit=${result.exitCode}`;
+    throw new Error(`observer discovery failed (${reason}): ${result.stderr.trim().slice(-240) || result.stdout.trim().slice(-240)}`);
+  }
+  if (payload.found !== true) return null;
+  const entry = record(payload.entry);
+  const stateDir = typeof entry.stateDir === "string" ? entry.stateDir : "";
+  if (!isSafeWebObserveStateDir(stateDir)) throw new Error(`observer discovery returned unsafe stateDir: ${stateDir}`);
+  return {
+    id,
+    node,
+    lane,
+    workspace: spec.workspace,
+    stateDir,
+    url: typeof entry.url === "string" ? entry.url : "",
+    targetPath: typeof entry.targetPath === "string" ? entry.targetPath : "",
+    status: typeof entry.status === "string" ? entry.status : null,
+    pid: typeof entry.pid === "number" ? entry.pid : null,
+    startedAt: typeof entry.startedAt === "string" ? entry.startedAt : null,
+    updatedAt: typeof entry.updatedAt === "string" ? entry.updatedAt : new Date().toISOString(),
+  };
+}
+
 function upsertWebObserveIndexEntry(entry: WebObserveIndexEntry): Record<string, unknown> {
   const path = webObserveIndexPath();
   try {