串流訊息

在建立訊息時，您可以設定 "stream": true 來使用伺服器發送事件 (SSE) 進行增量式串流回應。

使用 SDK 進行串流

我們的 Python 和 TypeScript SDK 提供多種串流方式。Python SDK 同時支援同步和非同步串流。詳情請參閱各 SDK 的文件。

事件類型

每個伺服器發送事件都包含一個命名的事件類型和相關的 JSON 資料。每個事件都會使用 SSE 事件名稱（例如 event: message_stop），並在其資料中包含相對應的事件 type。

每個串流使用以下事件流程：

message_start：包含一個帶有空 content 的 Message 物件。
一系列內容區塊，每個區塊都有一個 content_block_start、一個或多個 content_block_delta 事件，以及一個 content_block_stop 事件。每個內容區塊都有一個 index，對應於最終 Message content 陣列中的索引。
一個或多個 message_delta 事件，表示最終 Message 物件的頂層變更。
最後的 message_stop 事件。

Ping 事件

事件串流中可能還包含任意數量的 ping 事件。

錯誤事件

我們可能偶爾會在事件串流中發送錯誤。例如，在高使用量期間，您可能會收到 overloaded_error，這在非串流環境中通常對應於 HTTP 529：

錯誤範例
event: error
data: {"type": "error", "error": {"type": "overloaded_error", "message": "Overloaded"}}

其他事件

根據我們的版本控制政策，我們可能會添加新的事件類型，您的程式碼應該能夠優雅地處理未知的事件類型。

Delta 類型

每個 content_block_delta 事件都包含一個 delta，用於更新給定 index 處的 content 區塊。

文字 delta

文字內容區塊 delta 看起來像這樣：

文字 delta
event: content_block_delta
data: {"type": "content_block_delta","index": 0,"delta": {"type": "text_delta", "text": "ello frien"}}

輸入 JSON delta

tool_use 內容區塊的 delta 對應於區塊的 input 欄位的更新。為了支援最大的粒度，delta 是 部分 JSON 字串，而最終的 tool_use.input 始終是一個物件。

您可以累積字串 delta，並在收到 content_block_stop 事件後解析 JSON，方法是使用像 Pydantic 這樣的函式庫進行部分 JSON 解析，或使用我們的 SDK，它們提供了訪問已解析增量值的輔助工具。

tool_use 內容區塊 delta 看起來像這樣：

輸入 JSON delta
event: content_block_delta
data: {"type": "content_block_delta","index": 1,"delta": {"type": "input_json_delta","partial_json": "{\"location\": \"San Fra"}}}

注意：我們目前的模型只支援一次從 input 中發出一個完整的鍵值屬性。因此，在使用工具時，模型工作時可能會在串流事件之間出現延遲。一旦累積了一個 input 鍵值，我們會將它們作為多個帶有分塊部分 json 的 content_block_delta 事件發出，這樣格式就可以自動支援未來模型中的更細粒度。

原始 HTTP 串流回應

我們強烈建議在使用串流模式時使用我們的客戶端 SDK。但是，如果您正在建立直接的 API 整合，則需要自行處理這些事件。

串流回應由以下部分組成：

一個 message_start 事件
可能有多個內容區塊，每個區塊包含： a. 一個 content_block_start 事件 b. 可能有多個 content_block_delta 事件 c. 一個 content_block_stop 事件
一個 message_delta 事件
一個 message_stop 事件

回應中可能還分散著 ping 事件。有關格式的更多詳細信息，請參見事件類型。

基本串流請求

請求
curl https://api.anthropic.com/v1/messages \
     --header "anthropic-version: 2023-06-01" \
     --header "content-type: application/json" \
     --header "x-api-key: $ANTHROPIC_API_KEY" \
     --data \
'{
  "model": "claude-3-5-sonnet-20241022",
  "messages": [{"role": "user", "content": "Hello"}],
  "max_tokens": 256,
  "stream": true
}'

回應
event: message_start
data: {"type": "message_start", "message": {"id": "msg_1nZdL29xx5MUA1yADyHTEsnR8uuvGzszyY", "type": "message", "role": "assistant", "content": [], "model": "claude-3-5-sonnet-20241022", "stop_reason": null, "stop_sequence": null, "usage": {"input_tokens": 25, "output_tokens": 1}}}

event: content_block_start
data: {"type": "content_block_start", "index": 0, "content_block": {"type": "text", "text": ""}}

event: ping
data: {"type": "ping"}

event: content_block_delta
data: {"type": "content_block_delta", "index": 0, "delta": {"type": "text_delta", "text": "Hello"}}

event: content_block_delta
data: {"type": "content_block_delta", "index": 0, "delta": {"type": "text_delta", "text": "!"}}

event: content_block_stop
data: {"type": "content_block_stop", "index": 0}

event: message_delta
data: {"type": "message_delta", "delta": {"stop_reason": "end_turn", "stop_sequence":null}, "usage": {"output_tokens": 15}}

event: message_stop
data: {"type": "message_stop"}

使用工具的串流請求

在這個請求中，我們要求 Claude 使用工具來告訴我們天氣。

請求
  curl https://api.anthropic.com/v1/messages \
    -H "content-type: application/json" \
    -H "x-api-key: $ANTHROPIC_API_KEY" \
    -H "anthropic-version: 2023-06-01" \
    -d '{
      "model": "claude-3-5-sonnet-20241022",
      "max_tokens": 1024,
      "tools": [
        {
          "name": "get_weather",
          "description": "Get the current weather in a given location",
          "input_schema": {
            "type": "object",
            "properties": {
              "location": {
                "type": "string",
                "description": "The city and state, e.g. San Francisco, CA"
              }
            },
            "required": ["location"]
          }
        }
      ],
      "tool_choice": {"type": "any"},
      "messages": [
        {
          "role": "user",
          "content": "What is the weather like in San Francisco?"
        }
      ],
      "stream": true
    }'

回應
event: message_start
data: {"type":"message_start","message":{"id":"msg_014p7gG3wDgGV9EUtLvnow3U","type":"message","role":"assistant","model":"claude-3-haiku-20240307","stop_sequence":null,"usage":{"input_tokens":472,"output_tokens":2},"content":[],"stop_reason":null}}

event: content_block_start
data: {"type":"content_block_start","index":0,"content_block":{"type":"text","text":""}}

event: ping
data: {"type": "ping"}

event: content_block_delta
data: {"type":"content_block_delta","index":0,"delta":{"type":"text_delta","text":"Okay"}}

event: content_block_delta
data: {"type":"content_block_delta","index":0,"delta":{"type":"text_delta","text":","}}

event: content_block_delta
data: {"type":"content_block_delta","index":0,"delta":{"type":"text_delta","text":" let"}}

event: content_block_delta
data: {"type":"content_block_delta","index":0,"delta":{"type":"text_delta","text":"'s"}}

event: content_block_delta
data: {"type":"content_block_delta","index":0,"delta":{"type":"text_delta","text":" check"}}

event: content_block_delta
data: {"type":"content_block_delta","index":0,"delta":{"type":"text_delta","text":" the"}}

event: content_block_delta
data: {"type":"content_block_delta","index":0,"delta":{"type":"text_delta","text":" weather"}}

event: content_block_delta
data: {"type":"content_block_delta","index":0,"delta":{"type":"text_delta","text":" for"}}

event: content_block_delta
data: {"type":"content_block_delta","index":0,"delta":{"type":"text_delta","text":" San"}}

event: content_block_delta
data: {"type":"content_block_delta","index":0,"delta":{"type":"text_delta","text":" Francisco"}}

event: content_block_delta
data: {"type":"content_block_delta","index":0,"delta":{"type":"text_delta","text":","}}

event: content_block_delta
data: {"type":"content_block_delta","index":0,"delta":{"type":"text_delta","text":" CA"}}

event: content_block_delta
data: {"type":"content_block_delta","index":0,"delta":{"type":"text_delta","text":":"}}

event: content_block_stop
data: {"type":"content_block_stop","index":0}

event: content_block_start
data: {"type":"content_block_start","index":1,"content_block":{"type":"tool_use","id":"toolu_01T1x1fJ34qAmk2tNTrN7Up6","name":"get_weather","input":{}}}

event: content_block_delta
data: {"type":"content_block_delta","index":1,"delta":{"type":"input_json_delta","partial_json":""}}

event: content_block_delta
data: {"type":"content_block_delta","index":1,"delta":{"type":"input_json_delta","partial_json":"{\"location\":"}}

event: content_block_delta
data: {"type":"content_block_delta","index":1,"delta":{"type":"input_json_delta","partial_json":" \"San"}}

event: content_block_delta
data: {"type":"content_block_delta","index":1,"delta":{"type":"input_json_delta","partial_json":" Francisc"}}

event: content_block_delta
data: {"type":"content_block_delta","index":1,"delta":{"type":"input_json_delta","partial_json":"o,"}}

event: content_block_delta
data: {"type":"content_block_delta","index":1,"delta":{"type":"input_json_delta","partial_json":" CA\""}}

event: content_block_delta
data: {"type":"content_block_delta","index":1,"delta":{"type":"input_json_delta","partial_json":", "}}

event: content_block_delta
data: {"type":"content_block_delta","index":1,"delta":{"type":"input_json_delta","partial_json":"\"unit\": \"fah"}}

event: content_block_delta
data: {"type":"content_block_delta","index":1,"delta":{"type":"input_json_delta","partial_json":"renheit\"}"}}

event: content_block_stop
data: {"type":"content_block_stop","index":1}

event: message_delta
data: {"type":"message_delta","delta":{"stop_reason":"tool_use","stop_sequence":null},"usage":{"output_tokens":89}}

event: message_stop
data: {"type":"message_stop"}

使用 API

Vertex AI

Amazon Bedrock API

Anthropic API

使用 SDK 進行串流

事件類型

Ping 事件

錯誤事件

其他事件

Delta 類型

文字 delta

輸入 JSON delta

原始 HTTP 串流回應

基本串流請求

使用工具的串流請求

使用 API

Vertex AI

Amazon Bedrock API

Anthropic API

​使用 SDK 進行串流

​事件類型

​Ping 事件

​錯誤事件

​其他事件

​Delta 類型

​文字 delta

​輸入 JSON delta

​原始 HTTP 串流回應

​基本串流請求

​使用工具的串流請求

使用 SDK 進行串流

事件類型

Ping 事件

錯誤事件

其他事件

Delta 類型

文字 delta

輸入 JSON delta

原始 HTTP 串流回應

基本串流請求

使用工具的串流請求