diff --git a/dist/core/sdk.js b/dist/core/sdk.js
index 0000000..1111111 100644
--- a/dist/core/sdk.js
+++ b/dist/core/sdk.js
@@ -441,6 +441,8 @@ export async function createAgentSession(options = {}) {
             }
             return key;
         },
+        // PATCH: Pass extraParams through for provider-specific features (e.g., GLM-4.7 thinking mode)
+        extraParams: options.extraParams,
     });
     time("createAgent");
     // Restore messages if session has existing data
diff --git a/dist/core/sdk.d.ts b/dist/core/sdk.d.ts
index 0000000..1111111 100644
--- a/dist/core/sdk.d.ts
+++ b/dist/core/sdk.d.ts
@@ -79,6 +79,10 @@ export interface CreateAgentSessionOptions {
     sessionManager?: SessionManager;
     /** Settings manager. Default: SettingsManager.create(cwd, agentDir) */
     settingsManager?: SettingsManager;
+    /**
+     * Extra params to pass to the provider API (e.g., Z.AI GLM thinking mode params).
+     */
+    extraParams?: Record<string, unknown>;
 }
 /** Result from createAgentSession */
 export interface CreateAgentSessionResult {
diff --git a/dist/core/session-manager.js b/dist/core/session-manager.js
index b2aba5280d002253b0938b75aedbb9e6e6c4dcf8..67464efff535dbd7a8e6ed825aab2b305ca2aee2 100644
--- a/dist/core/session-manager.js
+++ b/dist/core/session-manager.js
@@ -161,6 +161,15 @@ export function buildSessionContext(entries, leafId, byId) {
     const messages = [];
     const appendMessage = (entry) => {
         if (entry.type === "message") {
+            // PATCH: Filter out empty error assistant messages to prevent session corruption
+            // When 429/500 errors occur during tool execution, empty error messages get persisted
+            // to the session file. These break the tool_use -> tool_result chain for Claude/Gemini.
+            const msg = entry.message;
+            if (msg.role === "assistant" &&
+                msg.stopReason === "error" &&
+                (!msg.content || msg.content.length === 0)) {
+                return; // Skip empty error messages
+            }
             messages.push(entry.message);
         }
         else if (entry.type === "custom_message") {