diff --git a/plugins/codex/scripts/codex-companion.mjs b/plugins/codex/scripts/codex-companion.mjs
index 201d1c7a..8d18aebc 100644
--- a/plugins/codex/scripts/codex-companion.mjs
+++ b/plugins/codex/scripts/codex-companion.mjs
@@ -313,6 +313,35 @@ async function resolveLatestTrackedTaskThread(cwd, options = {}) {
   const jobs = sortJobsNewestFirst(listJobs(workspaceRoot)).filter((job) => job.id !== options.excludeJobId);
   const activeTask = jobs.find((job) => job.jobClass === "task" && (job.status === "queued" || job.status === "running"));
   if (activeTask) {
+    // Check if the process is actually alive before blocking
+    if (activeTask.pid) {
+      try {
+        process.kill(activeTask.pid, 0);
+      } catch (err) {
+        // Process is dead but job status wasn't updated — mark it as failed and clean up
+        if (err.code === "ESRCH" || err.code === "EPERM") {
+          await upsertJob(workspaceRoot, {
+            id: activeTask.id,
+            status: "failed",
+            phase: "failed",
+            pid: null,
+            completedAt: new Date().toISOString(),
+            errorMessage: "Process exited unexpectedly while job status was 'running'."
+          });
+          // Re-fetch jobs after the update
+          const updatedJobs = sortJobsNewestFirst(listJobs(workspaceRoot)).filter((job) => job.id !== options.excludeJobId);
+          const newActiveTask = updatedJobs.find((job) => job.jobClass === "task" && (job.status === "queued" || job.status === "running"));
+          if (!newActiveTask) {
+            // Zombie job was cleaned up, proceed normally
+          } else {
+            throw new Error(`Task ${newActiveTask.id} is still running. Use /codex:status before continuing it.`);
+          }
+        } else {
+          throw new Error(`Task ${activeTask.id} is still running. Use /codex:status before continuing it.`);
+        }
+        return null;
+      }
+    }
     throw new Error(`Task ${activeTask.id} is still running. Use /codex:status before continuing it.`);
   }
 
@@ -457,7 +486,7 @@ async function executeTaskRun(request) {
     defaultPrompt: resumeThreadId ? DEFAULT_CONTINUE_PROMPT : "",
     model: request.model,
     effort: request.effort,
-    sandbox: request.write ? "workspace-write" : "read-only",
+    sandbox: request.fullAccess ? "danger-full-access" : (request.write ? "workspace-write" : "read-only"),
     onProgress: request.onProgress,
     persistThread: true,
     threadName: resumeThreadId ? null : buildPersistentTaskThreadName(request.prompt || DEFAULT_CONTINUE_PROMPT)
@@ -704,7 +733,7 @@ async function handleReview(argv) {
 async function handleTask(argv) {
   const { options, positionals } = parseCommandInput(argv, {
     valueOptions: ["model", "effort", "cwd", "prompt-file"],
-    booleanOptions: ["json", "write", "resume-last", "resume", "fresh", "background"],
+    booleanOptions: ["json", "write", "full-access", "resume-last", "resume", "fresh", "background"],
     aliasMap: {
       m: "model"
     }
diff --git a/plugins/codex/scripts/lib/tracked-jobs.mjs b/plugins/codex/scripts/lib/tracked-jobs.mjs
index 90286901..63c42238 100644
--- a/plugins/codex/scripts/lib/tracked-jobs.mjs
+++ b/plugins/codex/scripts/lib/tracked-jobs.mjs
@@ -1,7 +1,7 @@
 import fs from "node:fs";
 import process from "node:process";
 
-import { readJobFile, resolveJobFile, resolveJobLogFile, upsertJob, writeJobFile } from "./state.mjs";
+import { readJobFile, resolveJobFile, resolveJobLogFile, upsertJob, writeJobFile, loadState, saveState } from "./state.mjs";
 
 export const SESSION_ID_ENV = "CODEX_COMPANION_SESSION_ID";
 
@@ -9,6 +9,56 @@ export function nowIso() {
   return new Date().toISOString();
 }
 
+/**
+ * Check if a process with the given PID is still alive.
+ * Uses signal 0 (existence check) to avoid side effects.
+ * @param {number} pid
+ * @returns {boolean}
+ */
+export function isProcessAlive(pid) {
+  if (!Number.isFinite(pid) || pid <= 0) {
+    return false;
+  }
+  try {
+    // Signal 0 checks if process exists without sending any signal
+    process.kill(pid, 0);
+    return true;
+  } catch (e) {
+    // ESRCH = no such process   — process does not exist
+    // EPERM = permission denied  — process exists but we can't signal it
+    return e.code === "EPERM";
+  }
+}
+
+/**
+ * Sweep all jobs in state and mark zombie (dead PID) jobs as failed.
+ * This prevents zombie "running" jobs from blocking new task submissions.
+ * @param {string} cwd - workspace root
+ * @returns {Promise<number>} - number of jobs marked as failed
+ */
+export async function sweepZombieJobs(cwd) {
+  const state = loadState(cwd);
+  let zombiesFixed = 0;
+  const now = nowIso();
+
+  for (const job of state.jobs) {
+    if (job.status === "running" && job.pid) {
+      if (!isProcessAlive(job.pid)) {
+        console.warn(`[tracked-jobs] Zombie job detected: ${job.id} (PID ${job.pid}). Marking as failed.`);
+        job.status = "failed";
+        job.endedAt = now;
+        job.error = "Process died unexpectedly — marked failed by zombie sweep";
+        zombiesFixed++;
+      }
+    }
+  }
+
+  if (zombiesFixed > 0) {
+    saveState(cwd, state);
+  }
+  return zombiesFixed;
+}
+
 function normalizeProgressEvent(value) {
   if (value && typeof value === "object" && !Array.isArray(value)) {
     return {
@@ -140,6 +190,11 @@ function readStoredJobOrNull(workspaceRoot, jobId) {
 }
 
 export async function runTrackedJob(job, runner, options = {}) {
+  // FIX #216: Clean up zombie jobs before starting a new one.
+  // If a previous job's worker process died without updating state,
+  // its record stays stuck in "running" — blocking new tasks.
+  await sweepZombieJobs(job.workspaceRoot);
+
   const runningRecord = {
     ...job,
     status: "running",