task: add `--resume-thread <id>` — jobs killed by a usage limit cannot be resumed from the plugin

Summary

task can only resume the latest thread (--resume-last), and a background job killed by a usage limit is left as failed with no way to continue it from the plugin — even though /codex:result prints the thread's Codex session ID and the runtime already supports resumeThreadId.

Scenario (plugin 1.0.6, codex-cli 0.151.0, Linux)

1. Launch five /codex:rescue --background audits in parallel (read-only, --effort high).
2. The account's 5-hour window runs out mid-run. All five jobs end with:

   [codex] Codex error: You've hit your usage limit. ... try again at 3:40 PM.
   [codex] Turn failed.
   

   Each had already read a large part of the repo (the expensive part).
3. After the reset, there is no plugin way to continue them: --resume-last only targets the newest thread, and /codex:result just prints Resume in Codex: codex resume <id> — i.e. it hands the id back and sends the user to the terminal.

Workaround that works today: codex exec --sandbox read-only resume <id> "<continue prompt>" per thread.

Proposed fix (small)

Add --resume-thread <id> to task, mutually exclusive with --resume-last / --fresh, and thread it through buildTaskRequest → executeTaskRun so both the foreground and background paths honour it. Patch against 1.0.6 (companion script + the codex-cli-runtime skill so the rescue subagent knows the flag) is below — ~40 lines, no behaviour change for existing flags.

A natural follow-up: when a job fails on a usage-limit error (the message carries the reset time), keep the thread id in the job record and let /codex:status offer a one-liner to resume it after the reset, instead of marking it terminally failed.

Patch

--- a/scripts/codex-companion.mjs
+++ b/scripts/codex-companion.mjs
@@ -79,7 +79,7 @@
       "  node scripts/codex-companion.mjs setup [--enable-review-gate|--disable-review-gate] [--json]",
       "  node scripts/codex-companion.mjs review [--wait|--background] [--base <ref>] [--scope <auto|working-tree|branch>]",
       "  node scripts/codex-companion.mjs adversarial-review [--wait|--background] [--base <ref>] [--scope <auto|working-tree|branch>] [focus text]",
-      "  node scripts/codex-companion.mjs task [--background] [--write] [--resume-last|--resume|--fresh] [--model <model|spark>] [--effort <none|minimal|low|medium|high|xhigh>] [prompt]",
+      "  node scripts/codex-companion.mjs task [--background] [--write] [--resume-last|--resume|--resume-thread <id>|--fresh] [--model <model|spark>] [--effort <none|minimal|low|medium|high|xhigh>] [prompt]",
       "  node scripts/codex-companion.mjs transfer [--source <claude-jsonl>] [--json]",
       "  node scripts/codex-companion.mjs status [job-id] [--all] [--json]",
       "  node scripts/codex-companion.mjs result [job-id] [--json]",
@@ -464,11 +464,14 @@
 
   const taskMetadata = buildTaskRunMetadata({
     prompt: request.prompt,
-    resumeLast: request.resumeLast
+    resumeLast: request.resumeLast || Boolean(request.resumeThread)
   });
 
   let resumeThreadId = null;
-  if (request.resumeLast) {
+  if (request.resumeThread) {
+    // Explicit thread id (e.g. a job cut by a usage limit): skip the latest-thread lookup.
+    resumeThreadId = String(request.resumeThread).trim();
+  } else if (request.resumeLast) {
     const latestThread = await resolveLatestTrackedTaskThread(workspaceRoot, {
       excludeJobId: request.jobId
     });
@@ -479,7 +482,7 @@
   }
 
   if (!request.prompt && !resumeThreadId) {
-    throw new Error("Provide a prompt, a prompt file, piped stdin, or use --resume-last.");
+    throw new Error("Provide a prompt, a prompt file, piped stdin, or use --resume-last / --resume-thread <id>.");
   }
 
   const result = await runAppServerTurn(workspaceRoot, {
@@ -601,7 +604,7 @@
   });
 }
 
-function buildTaskRequest({ cwd, model, effort, prompt, write, resumeLast, jobId }) {
+function buildTaskRequest({ cwd, model, effort, prompt, write, resumeLast, resumeThread = null, jobId }) {
   return {
     cwd,
     model,
@@ -609,6 +612,7 @@
     prompt,
     write,
     resumeLast,
+    resumeThread,
     jobId
   };
 }
@@ -649,9 +653,9 @@
   return positionalPrompt || readStdinIfPiped();
 }
 
-function requireTaskRequest(prompt, resumeLast) {
-  if (!prompt && !resumeLast) {
-    throw new Error("Provide a prompt, a prompt file, piped stdin, or use --resume-last.");
+function requireTaskRequest(prompt, resumeLast, resumeThread = null) {
+  if (!prompt && !resumeLast && !resumeThread) {
+    throw new Error("Provide a prompt, a prompt file, piped stdin, or use --resume-last / --resume-thread <id>.");
   }
 }
 
@@ -761,7 +765,7 @@
 
 async function handleTask(argv) {
   const { options, positionals } = parseCommandInput(argv, {
-    valueOptions: ["model", "effort", "cwd", "prompt-file"],
+    valueOptions: ["model", "effort", "cwd", "prompt-file", "resume-thread"],
     booleanOptions: ["json", "write", "resume-last", "resume", "fresh", "background"],
     aliasMap: {
       m: "model"
@@ -775,19 +779,23 @@
   const prompt = readTaskPrompt(cwd, options, positionals);
 
   const resumeLast = Boolean(options["resume-last"] || options.resume);
+  const resumeThread = options["resume-thread"] ? String(options["resume-thread"]).trim() : null;
   const fresh = Boolean(options.fresh);
-  if (resumeLast && fresh) {
-    throw new Error("Choose either --resume/--resume-last or --fresh.");
+  if ((resumeLast || resumeThread) && fresh) {
+    throw new Error("Choose either --resume/--resume-last/--resume-thread or --fresh.");
+  }
+  if (resumeLast && resumeThread) {
+    throw new Error("Choose either --resume-last or --resume-thread <id>, not both.");
   }
   const write = Boolean(options.write);
   const taskMetadata = buildTaskRunMetadata({
     prompt,
-    resumeLast
+    resumeLast: resumeLast || Boolean(resumeThread)
   });
 
   if (options.background) {
     ensureCodexAvailable(cwd);
-    requireTaskRequest(prompt, resumeLast);
+    requireTaskRequest(prompt, resumeLast, resumeThread);
 
     const job = buildTaskJob(workspaceRoot, taskMetadata, write);
     const request = buildTaskRequest({
@@ -797,6 +805,7 @@
       prompt,
       write,
       resumeLast,
+      resumeThread,
       jobId: job.id
     });
     const { payload } = enqueueBackgroundTask(cwd, job, request);
@@ -815,6 +824,7 @@
         prompt,
         write,
         resumeLast,
+        resumeThread,
         jobId: job.id,
         onProgress: progress
       }),
--- a/plugins/codex/skills/codex-cli-runtime/SKILL.md
+++ b/plugins/codex/skills/codex-cli-runtime/SKILL.md
@@ -30,6 +30,7 @@
 - If the forwarded request includes `--effort`, pass it through to `task`.
 - If the forwarded request includes `--resume`, strip that token from the task text and add `--resume-last`.
 - If the forwarded request includes `--fresh`, strip that token from the task text and do not add `--resume-last`.
+- If the forwarded request includes `--resume-thread <id>` (a Codex session/thread UUID, e.g. from a `/codex:result` line "Codex session ID:" of a job that failed on a usage limit), strip both tokens from the task text and pass `--resume-thread <id>` to `task`. This resumes THAT thread with its context instead of the latest one.
 - `--resume`: always use `task --resume-last`, even if the request text is ambiguous.
 - `--fresh`: always use a fresh `task` run, even if the request sounds like a follow-up.
 - `--effort`: accepted values are `none`, `minimal`, `low`, `medium`, `high`, `xhigh`.

Start in scripts/codex-companion.mjs at handleTask, buildTaskRequest, and executeTaskRun, then review plugins/codex/skills/codex-cli-runtime/SKILL.md. Verify that --resume-thread accepts an explicit session ID, works in foreground and background runs, and is rejected with --resume-last or --fresh; update the runtime guidance accordingly.