From 49740a463f1d262290ac34793b61515fc3987b4d Mon Sep 17 00:00:00 2001
From: Hiep Le <69354317+hieptl@users.noreply.github.com>
Date: Tue, 16 Dec 2025 20:14:19 +0700
Subject: [PATCH] fix(frontend): clicking think block in conversation pane
 breaks ui (v1 conversations) (#12057)

---
 .../v1/chat/event-content-helpers/get-event-content.tsx   | 3 +++
 .../chat/event-content-helpers/get-observation-content.ts | 8 +++++++-
 frontend/src/types/v1/core/base/observation.ts            | 2 +-
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/frontend/src/components/v1/chat/event-content-helpers/get-event-content.tsx b/frontend/src/components/v1/chat/event-content-helpers/get-event-content.tsx
index d9b9bf2d2d..dec57f385f 100644
--- a/frontend/src/components/v1/chat/event-content-helpers/get-event-content.tsx
+++ b/frontend/src/components/v1/chat/event-content-helpers/get-event-content.tsx
@@ -159,6 +159,9 @@ const getObservationEventTitle = (event: OpenHandsEvent): React.ReactNode => {
       }
       break;
     }
+    case "ThinkObservation":
+      observationKey = "OBSERVATION_MESSAGE$THINK";
+      break;
     default:
       // For unknown observations, use the type name
       return observationType.replace("Observation", "").toUpperCase();
diff --git a/frontend/src/components/v1/chat/event-content-helpers/get-observation-content.ts b/frontend/src/components/v1/chat/event-content-helpers/get-observation-content.ts
index bf443ea71c..7fb1c2ce1c 100644
--- a/frontend/src/components/v1/chat/event-content-helpers/get-observation-content.ts
+++ b/frontend/src/components/v1/chat/event-content-helpers/get-observation-content.ts
@@ -190,7 +190,13 @@ const getThinkObservationContent = (
   event: ObservationEvent<ThinkObservation>,
 ): string => {
   const { observation } = event;
-  return observation.content || "";
+
+  const textContent = observation.content
+    .filter((c) => c.type === "text")
+    .map((c) => c.text)
+    .join("\n");
+
+  return textContent || "";
 };
 
 const getFinishObservationContent = (
diff --git a/frontend/src/types/v1/core/base/observation.ts b/frontend/src/types/v1/core/base/observation.ts
index 42726c2b32..a1c8a1a48d 100644
--- a/frontend/src/types/v1/core/base/observation.ts
+++ b/frontend/src/types/v1/core/base/observation.ts
@@ -36,7 +36,7 @@ export interface ThinkObservation extends ObservationBase<"ThinkObservation"> {
   /**
    * Confirmation message. DEFAULT: "Your thought has been logged."
    */
-  content: string;
+  content: Array<TextContent | ImageContent>;
 }
 
 export interface BrowserObservation extends ObservationBase<"BrowserObservation"> {