本指南假设您了解什么是双重发送，您可以在双重发送概念指南中了解。 本指南涵盖双重发送的 reject 选项，它通过抛出错误拒绝图的新运行，并继续原始运行直到完成。下面是使用 reject 选项的快速示例。

​
设置

首先，我们将定义一个快速辅助函数来打印 JS 和 CURL 模型输出（如果使用 Python，可以跳过此步骤）：
  • Javascript
  • CURL
function prettyPrint(m) {
  const padded = " " + m['type'] + " ";
  const sepLen = Math.floor((80 - padded.length) / 2);
  const sep = "=".repeat(sepLen);
  const secondSep = sep + (padded.length % 2 ? "=" : "");

  console.log(`${sep}${padded}${secondSep}`);
  console.log("\n\n");
  console.log(m.content);
}
现在，让我们导入所需的包并实例化客户端、助手和线程。
  • Python
  • Javascript
  • CURL
import httpx
from langchain_core.messages import convert_to_messages
from langgraph_sdk import get_client

client = get_client(url=<DEPLOYMENT_URL>)
# Using the graph deployed with the name "agent"
assistant_id = "agent"
thread = await client.threads.create()

​
创建运行

现在我们可以运行一个线程并尝试使用”reject”选项运行第二个线程，由于我们已经启动了运行，因此应该失败：
  • Python
  • Javascript
  • CURL
run = await client.runs.create(
    thread["thread_id"],
    assistant_id,
    input={"messages": [{"role": "user", "content": "what's the weather in sf?"}]},
)
try:
    await client.runs.create(
        thread["thread_id"],
        assistant_id,
        input={
            "messages": [{"role": "user", "content": "what's the weather in nyc?"}]
        },
        multitask_strategy="reject",
    )
except httpx.HTTPStatusError as e:
    print("Failed to start concurrent run", e)
Output: 
Failed to start concurrent run Client error '409 Conflict' for url 'http://localhost:8123/threads/f9e7088b-8028-4e5c-88d2-9cc9a2870e50/runs'
For more information check: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/409

​
View run results

We can verify that the original thread finished executing:
  • Python
  • Javascript
  • CURL
# wait until the original run completes
await client.runs.join(thread["thread_id"], run["run_id"])

state = await client.threads.get_state(thread["thread_id"])

for m in convert_to_messages(state["values"]["messages"]):
    m.pretty_print()
Output: 
================================ Human Message =================================

what's the weather in sf?
================================== Ai Message ==================================

[{'id': 'toolu_01CyewEifV2Kmi7EFKHbMDr1', 'input': {'query': 'weather in san francisco'}, 'name': 'tavily_search_results_json', 'type': 'tool_use'}]
Tool Calls:
tavily_search_results_json (toolu_01CyewEifV2Kmi7EFKHbMDr1)
Call ID: toolu_01CyewEifV2Kmi7EFKHbMDr1
Args:
query: weather in san francisco
================================= Tool Message =================================
Name: tavily_search_results_json

[{"url": "https://www.accuweather.com/en/us/san-francisco/94103/june-weather/347629", "content": "Get the monthly weather forecast for San Francisco, CA, including daily high/low, historical averages, to help you plan ahead."}]
================================== Ai Message ==================================

According to the search results from Tavily, the current weather in San Francisco is:

The average high temperature in San Francisco in June is around 65°F (18°C), with average lows around 54°F (12°C). June tends to be one of the cooler and foggier months in San Francisco due to the marine layer of fog that often blankets the city during the summer months.

Some key points about the typical June weather in San Francisco:

* Mild temperatures with highs in the 60s F and lows in the 50s F
* Foggy mornings that often burn off to sunny afternoons
* Little to no rainfall, as June falls in the dry season
* Breezy conditions, with winds off the Pacific Ocean
* Layers are recommended for changing weather conditions

So in summary, you can expect mild, foggy mornings giving way to sunny but cool afternoons in San Francisco this time of year. The marine layer keeps temperatures moderate compared to other parts of California in June.
Edit the source of this page on GitHub.
Connect these docs programmatically to Claude, VSCode, and more via MCP for real-time answers.