fix: preserve recent Codex context projections

VACInc · VACInc · commit 68f3c80ec05d · 2026-05-17T10:29:49.000-04:00
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -25,6 +25,7 @@ Docs: https://docs.openclaw.ai
 
 ### Fixes
 
+- Codex app-server: keep recent context-engine messages when oversized projected history is truncated, so short follow-ups in long channel sessions do not fall back to stale earlier turns.
 - Feishu: refresh inbound session delivery context for DM, group, and broadcast turns so later replies do not inherit stale WebChat routing. Fixes #78274.
 - QA-Lab/qa-channel: attach redacted agent tool-start traces to outbound `QaBusMessage` records so scenarios can assert actual tool use instead of relying only on reply text. Fixes #67637. Thanks @100yenadmin.
 - QA-Lab: fail live runtime parity reports when assistant-message usage is missing, preventing `0 vs 0` live token rows from being reported as passing proof. Fixes #80411. Thanks @100yenadmin.
diff --git a/extensions/codex/src/app-server/context-engine-projection.test.ts b/extensions/codex/src/app-server/context-engine-projection.test.ts
@@ -154,6 +154,32 @@ describe("projectContextEngineAssemblyForCodex", () => {
     expect(result.promptText.length).toBeLessThan(25_000);
   });
 
+  it("keeps recent context when the rendered conversation overflows", () => {
+    const result = projectContextEngineAssemblyForCodex({
+      assembledMessages: [
+        textMessage("assistant", `old discrawl setup from previous day ${"x".repeat(5_850)}`),
+        ...Array.from({ length: 5 }, (_, index) =>
+          textMessage("assistant", `stale filler ${index}:${"x".repeat(5_850)}`),
+        ),
+        textMessage(
+          "user",
+          "have Codex CLI do it via /goal. tell it in a SEPARATE repo; create recrawl",
+        ),
+        textMessage("assistant", "codex exec -C /tmp/recrawl started"),
+      ],
+      originalHistoryMessages: [],
+      prompt: "?",
+    });
+
+    expect(result.promptText).toContain("[truncated ");
+    expect(result.promptText).toContain("from older context");
+    expect(result.promptText).not.toContain("old discrawl setup from previous day");
+    expect(result.promptText).toContain("create recrawl");
+    expect(result.promptText).toContain("codex exec -C /tmp/recrawl started");
+    expect(result.promptText).toContain("Current user request:\n?");
+    expect(result.promptText.length).toBeLessThan(25_000);
+  });
+
   it("can scale the rendered context cap for larger Codex context windows", () => {
     const result = projectContextEngineAssemblyForCodex({
       assembledMessages: Array.from({ length: 12 }, (_, index) =>
diff --git a/extensions/codex/src/app-server/context-engine-projection.ts b/extensions/codex/src/app-server/context-engine-projection.ts
@@ -47,7 +47,7 @@ export function projectContextEngineAssemblyForCodex(params: {
         CONTEXT_SAFETY_NOTE,
         "",
         CONTEXT_OPEN,
-        truncateText(renderedContext, maxRenderedContextChars),
+        truncateOlderContext(renderedContext, maxRenderedContextChars),
         CONTEXT_CLOSE,
         "",
         REQUEST_HEADER,
@@ -381,3 +381,23 @@ function truncateText(text: string, maxChars: number): string {
     ? `${text.slice(0, maxChars)}\n[truncated ${text.length - maxChars} chars]`
     : text;
 }
+
+function truncateOlderContext(text: string, maxChars: number): string {
+  if (text.length <= maxChars) {
+    return text;
+  }
+  if (maxChars <= 0) {
+    return "";
+  }
+
+  const buildMarker = (omittedChars: number): string =>
+    `[truncated ${omittedChars} chars from older context]\n`;
+  let marker = buildMarker(text.length - maxChars);
+  let tailChars = Math.max(0, maxChars - marker.length);
+  marker = buildMarker(text.length - tailChars);
+  if (marker.length >= maxChars) {
+    return marker.slice(0, maxChars);
+  }
+  tailChars = maxChars - marker.length;
+  return `${marker}${text.slice(text.length - tailChars).trimStart()}`;
+}
