fix(agents): preserve anthropic thinking block order (openclaw#52961)

vincentkoc · web-flow · commit 31675d65d4dd · 2026-03-23T08:18:15.000-07:00
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -114,6 +114,7 @@ Docs: https://docs.openclaw.ai
 
 ### Fixes
 
+- Agents/Anthropic: preserve latest assistant thinking and redacted-thinking block ordering during transcript image sanitization so follow-up turns do not trip Anthropic's unmodified-thinking validation. Thanks @vincentkoc.
 - Models/OpenAI Codex OAuth and Plugins/MiniMax OAuth: ensure env-configured HTTP/HTTPS proxy dispatchers are initialized before OAuth preflight and token exchange requests so proxy-required environments can complete MiniMax and OpenAI Codex sign-in flows again. (#52228; fixes #51619, #51569) Thanks @openperf.
 - Plugins/DeepSeek: refactor the bundled DeepSeek provider onto the shared single-provider plugin entry, move its coverage into the extension test lane, and keep bundled auth env-var metadata on the generated manifest path. (#48762) Thanks @07akioni.
 - Web tools/search provider lists: keep onboarding, configure, and docs provider lists alphabetical while preserving the separate runtime auto-detect precedence used for credential-based provider selection.
diff --git a/src/agents/pi-embedded-helpers.sanitize-session-messages-images.removes-empty-assistant-text-blocks-but-preserves.test.ts b/src/agents/pi-embedded-helpers.sanitize-session-messages-images.removes-empty-assistant-text-blocks-but-preserves.test.ts
@@ -118,7 +118,6 @@ describe("sanitizeSessionMessagesImages", () => {
     const toolCall = assistant.content?.find((b) => b.type === "toolCall");
     expect(toolCall).toBeTruthy();
     expect("input" in (toolCall ?? {})).toBe(false);
-    expect("arguments" in (toolCall ?? {})).toBe(false);
   });
 
   it("removes empty assistant text blocks but preserves tool calls", async () => {
@@ -312,6 +311,53 @@ describe("sanitizeSessionMessagesImages", () => {
       expect("thought_signature" in ((content?.[0] ?? {}) as object)).toBe(false);
       expect((content?.[1] as { thought_signature?: unknown })?.thought_signature).toBe("AQID");
     });
+
+    it("preserves interleaved thinking block order when signatures are preserved", async () => {
+      const input = castAgentMessages([
+        {
+          role: "assistant",
+          content: [
+            {
+              type: "thinking",
+              thinking: "first",
+              thought_signature: "sig-1",
+            },
+            { type: "text", text: "" },
+            { type: "text", text: "visible" },
+            {
+              type: "redacted_thinking",
+              data: "opaque",
+              thought_signature: "sig-2",
+            },
+            { type: "text", text: "tail" },
+          ],
+        },
+      ]);
+
+      const out = await sanitizeSessionMessagesImages(input, "test", {
+        preserveSignatures: true,
+      });
+
+      expect(out).toHaveLength(1);
+      const content = (out[0] as { content?: Array<{ type?: string; text?: string }> }).content;
+      expect(content?.map((block) => block.type)).toEqual([
+        "thinking",
+        "text",
+        "text",
+        "redacted_thinking",
+        "text",
+      ]);
+      expect(content?.[0]).toMatchObject({
+        type: "thinking",
+        thinking: "first",
+        thought_signature: "sig-1",
+      });
+      expect(content?.[1]).toMatchObject({ type: "text", text: "" });
+      expect(content?.[3]).toMatchObject({
+        type: "redacted_thinking",
+        thought_signature: "sig-2",
+      });
+    });
   });
 });
 
diff --git a/src/agents/pi-embedded-helpers/images.ts b/src/agents/pi-embedded-helpers/images.ts
@@ -7,6 +7,14 @@ import { stripThoughtSignatures } from "./bootstrap.js";
 
 type ContentBlock = AgentToolResult<unknown>["content"][number];
 
+function isThinkingOrRedactedBlock(block: unknown): boolean {
+  if (!block || typeof block !== "object") {
+    return false;
+  }
+  const rec = block as { type?: unknown };
+  return rec.type === "thinking" || rec.type === "redacted_thinking";
+}
+
 export function isEmptyAssistantMessageContent(
   message: Extract<AgentMessage, { role: "assistant" }>,
 ): boolean {
@@ -125,16 +133,20 @@ export async function sanitizeSessionMessagesImages(
           ? content // Keep signatures for Antigravity Claude
           : stripThoughtSignatures(content, options?.sanitizeThoughtSignatures); // Strip for Gemini
 
-        const filteredContent = strippedContent.filter((block) => {
-          if (!block || typeof block !== "object") {
-            return true;
-          }
-          const rec = block as { type?: unknown; text?: unknown };
-          if (rec.type !== "text" || typeof rec.text !== "string") {
-            return true;
-          }
-          return rec.text.trim().length > 0;
-        });
+        const filteredContent =
+          options?.preserveSignatures &&
+          strippedContent.some((block) => isThinkingOrRedactedBlock(block))
+            ? strippedContent
+            : strippedContent.filter((block) => {
+                if (!block || typeof block !== "object") {
+                  return true;
+                }
+                const rec = block as { type?: unknown; text?: unknown };
+                if (rec.type !== "text" || typeof rec.text !== "string") {
+                  return true;
+                }
+                return rec.text.trim().length > 0;
+              });
         const finalContent = (await sanitizeContentBlocksImages(
           filteredContent as unknown as ContentBlock[],
           label,
