diff --git a/astrbot/core/provider/sources/anthropic_source.py b/astrbot/core/provider/sources/anthropic_source.py
index 0ff61e393..6c9f62e29 100644
--- a/astrbot/core/provider/sources/anthropic_source.py
+++ b/astrbot/core/provider/sources/anthropic_source.py
@@ -68,7 +68,7 @@ def _prepare_payload(self, messages: list[dict]):
                 blocks = []
                 if isinstance(message["content"], str):
                     blocks.append({"type": "text", "text": message["content"]})
-                if "tool_calls" in message:
+                if "tool_calls" in message and isinstance(message["tool_calls"], list):
                     for tool_call in message["tool_calls"]:
                         blocks.append(  # noqa: PERF401
                             {
@@ -132,6 +132,9 @@ async def _query(self, payloads: dict, tools: ToolSet | None) -> LLMResponse:
 
         extra_body = self.provider_config.get("custom_extra_body", {})
 
+        if "max_tokens" not in payloads:
+            payloads["max_tokens"] = 1024
+
         completion = await self.client.messages.create(
             **payloads, stream=False, extra_body=extra_body
         )
@@ -181,6 +184,9 @@ async def _query_stream(
         usage = TokenUsage()
         extra_body = self.provider_config.get("custom_extra_body", {})
 
+        if "max_tokens" not in payloads:
+            payloads["max_tokens"] = 1024
+
         async with self.client.messages.stream(
             **payloads, extra_body=extra_body
         ) as stream:
@@ -342,11 +348,11 @@ async def text_chat(
 
     async def text_chat_stream(
         self,
-        prompt,
+        prompt=None,
         session_id=None,
-        image_urls=...,
+        image_urls=None,
         func_tool=None,
-        contexts=...,
+        contexts=None,
         system_prompt=None,
         tool_calls_result=None,
         model=None,