Capacidades del modelo

Transmisión de Mensajes

Aprende cómo transmitir respuestas de mensajes de forma incremental usando eventos enviados por el servidor.

Al crear un Mensaje, puedes establecer "stream": true para transmitir la respuesta de forma incremental usando eventos enviados por el servidor (SSE).

Transmisión con SDKs

Nuestros SDKs de Python y TypeScript ofrecen múltiples formas de transmisión. El SDK de Python permite transmisiones tanto síncronas como asincrónicas. Consulta la documentación en cada SDK para obtener más detalles.

import anthropic

client = anthropic.Anthropic()

with client.messages.stream(
    max_tokens=1024,
    messages=[{"role": "user", "content": "Hello"}],
    model="claude-opus-4-6",
) as stream:
    for text in stream.text_stream:
        print(text, end="", flush=True)

Obtener el mensaje final sin manejar eventos

Si no necesitas procesar el texto a medida que llega, los SDKs proporcionan una forma de usar la transmisión bajo el capó mientras devuelven el objeto Message completo — idéntico a lo que devuelve .create(). Esto es especialmente útil para solicitudes con valores grandes de max_tokens, donde los SDKs requieren transmisión para evitar tiempos de espera HTTP.

La llamada .stream() mantiene la conexión HTTP activa con eventos enviados por el servidor, luego .get_final_message() (Python) o .finalMessage() (TypeScript) acumula todos los eventos y devuelve el objeto Message completo. No se necesita código de manejo de eventos.

Tipos de eventos

Cada evento enviado por el servidor incluye un tipo de evento nombrado y datos JSON asociados. Cada evento utilizará un nombre de evento SSE (por ejemplo, event: message_stop), e incluirá el type de evento coincidente en sus datos.

Cada transmisión utiliza el siguiente flujo de eventos:

message_start: contiene un objeto Message con content vacío.
Una serie de bloques de contenido, cada uno de los cuales tiene un evento content_block_start, uno o más eventos content_block_delta, y un evento content_block_stop. Cada bloque de contenido tendrá un index que corresponde a su índice en el array final de content del Mensaje.
Uno o más eventos message_delta, indicando cambios de nivel superior al objeto final Message.
Un evento final message_stop.

Los conteos de tokens mostrados en el campo usage del evento message_delta son acumulativos.

Eventos ping

Los flujos de eventos también pueden incluir cualquier número de eventos ping.

Eventos de error

Ocasionalmente podemos enviar errores en el flujo de eventos. Por ejemplo, durante períodos de alto uso, puedes recibir un overloaded_error, que normalmente correspondería a un HTTP 529 en un contexto sin transmisión:

Ejemplo de error

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

Otros eventos

De conformidad con nuestra política de versionado, podemos agregar nuevos tipos de eventos, y tu código debe manejar tipos de eventos desconocidos de manera elegante.

Tipos de delta de bloque de contenido

Cada evento content_block_delta contiene un delta de un tipo que actualiza el bloque de content en un index dado.

Delta de texto

Un delta de bloque de contenido text se ve así:

Delta de texto

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

Delta JSON de entrada

Los deltas para bloques de contenido tool_use corresponden a actualizaciones para el campo input del bloque. Para soportar la máxima granularidad, los deltas son cadenas JSON parciales, mientras que el tool_use.input final es siempre un objeto.

Puedes acumular los deltas de cadena y analizar el JSON una vez que recibas un evento content_block_stop, usando una biblioteca como Pydantic para hacer análisis parcial de JSON, o usando nuestros SDKs, que proporcionan ayudantes para acceder a valores incrementales analizados.

Un delta de bloque de contenido tool_use se ve así:

Delta JSON de entrada

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

Nota: Nuestros modelos actuales solo soportan emitir una propiedad de clave y valor completa de input a la vez. Como tal, cuando se usan herramientas, puede haber retrasos entre eventos de transmisión mientras el modelo está trabajando. Una vez que se acumula una clave y valor de input, los emitimos como múltiples eventos content_block_delta con json parcial dividido en fragmentos para que el formato pueda soportar automáticamente una granularidad más fina en modelos futuros.

Delta de pensamiento

Cuando se usa pensamiento extendido con transmisión habilitada, recibirás contenido de pensamiento a través de eventos thinking_delta. Estos deltas corresponden al campo thinking de los bloques de contenido thinking.

Para contenido de pensamiento, se envía un evento especial signature_delta justo antes del evento content_block_stop. Esta firma se utiliza para verificar la integridad del bloque de pensamiento.

Un delta de pensamiento típico se ve así:

Delta de pensamiento

event: content_block_delta
data: {"type": "content_block_delta", "index": 0, "delta": {"type": "thinking_delta", "thinking": "I need to find the GCD of 1071 and 462 using the Euclidean algorithm.\n\n1071 = 2 × 462 + 147"}}

El delta de firma se ve así:

Delta de firma

event: content_block_delta
data: {"type": "content_block_delta", "index": 0, "delta": {"type": "signature_delta", "signature": "EqQBCgIYAhIM1gbcDa9GJwZA2b3hGgxBdjrkzLoky3dl1pkiMOYds..."}}

Respuesta de flujo HTTP completa

Recomendamos encarecidamente que uses nuestros SDKs de cliente cuando uses el modo de transmisión. Sin embargo, si estás construyendo una integración directa de API, necesitarás manejar estos eventos tú mismo.

Una respuesta de transmisión se compone de:

Un evento message_start
Potencialmente múltiples bloques de contenido, cada uno de los cuales contiene:
- Un evento content_block_start
- Potencialmente múltiples eventos content_block_delta
- Un evento content_block_stop
Un evento message_delta
Un evento message_stop

También puede haber eventos ping dispersos a lo largo de la respuesta. Consulta Tipos de eventos para obtener más detalles sobre el formato.

Solicitud de transmisión básica

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-opus-4-6",
  "messages": [{"role": "user", "content": "Hello"}],
  "max_tokens": 256,
  "stream": true
}'

Respuesta

event: message_start
data: {"type": "message_start", "message": {"id": "msg_1nZdL29xx5MUA1yADyHTEsnR8uuvGzszyY", "type": "message", "role": "assistant", "content": [], "model": "claude-opus-4-6", "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"}

Solicitud de transmisión con uso de herramientas

El uso de herramientas soporta transmisión de grano fino para valores de parámetros. Habilítalo por herramienta con eager_input_streaming.

En esta solicitud, le pedimos a Claude que use una herramienta para decirnos el clima.

Respuesta

event: message_start
data: {"type":"message_start","message":{"id":"msg_014p7gG3wDgGV9EUtLvnow3U","type":"message","role":"assistant","model":"claude-opus-4-6","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"}

Solicitud de transmisión con pensamiento extendido

En esta solicitud, habilitamos el pensamiento extendido con transmisión para ver el razonamiento paso a paso de Claude.

Respuesta

event: message_start
data: {"type": "message_start", "message": {"id": "msg_01...", "type": "message", "role": "assistant", "content": [], "model": "claude-opus-4-6", "stop_reason": null, "stop_sequence": null}}

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

event: content_block_delta
data: {"type": "content_block_delta", "index": 0, "delta": {"type": "thinking_delta", "thinking": "I need to find the GCD of 1071 and 462 using the Euclidean algorithm.\n\n1071 = 2 × 462 + 147"}}

event: content_block_delta
data: {"type": "content_block_delta", "index": 0, "delta": {"type": "thinking_delta", "thinking": "\n462 = 3 × 147 + 21"}}

event: content_block_delta
data: {"type": "content_block_delta", "index": 0, "delta": {"type": "thinking_delta", "thinking": "\n147 = 7 × 21 + 0"}}

event: content_block_delta
data: {"type": "content_block_delta", "index": 0, "delta": {"type": "thinking_delta", "thinking": "\nThe remainder is 0, so GCD(1071, 462) = 21."}}

event: content_block_delta
data: {"type": "content_block_delta", "index": 0, "delta": {"type": "signature_delta", "signature": "EqQBCgIYAhIM1gbcDa9GJwZA2b3hGgxBdjrkzLoky3dl1pkiMOYds..."}}

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": "text", "text": ""}}

event: content_block_delta
data: {"type": "content_block_delta", "index": 1, "delta": {"type": "text_delta", "text": "The greatest common divisor of 1071 and 462 is **21**."}}

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

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

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

Solicitud de transmisión con uso de herramienta de búsqueda web

En esta solicitud, le pedimos a Claude que busque en la web información actual sobre el clima.

Respuesta

event: message_start
data: {"type":"message_start","message":{"id":"msg_01G...","type":"message","role":"assistant","model":"claude-opus-4-6","content":[],"stop_reason":null,"stop_sequence":null,"usage":{"input_tokens":2679,"cache_creation_input_tokens":0,"cache_read_input_tokens":0,"output_tokens":3}}}

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

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

event: content_block_delta
data: {"type":"content_block_delta","index":0,"delta":{"type":"text_delta","text":" the current weather in New York City for you"}}

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

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":"server_tool_use","id":"srvtoolu_014hJH82Qum7Td6UV8gDXThB","name":"web_search","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":"{\"query"}}

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":" \"weather"}}

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

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

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

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

event: content_block_start
data: {"type":"content_block_start","index":2,"content_block":{"type":"web_search_tool_result","tool_use_id":"srvtoolu_014hJH82Qum7Td6UV8gDXThB","content":[{"type":"web_search_result","title":"Weather in New York City in May 2025 (New York) - detailed Weather Forecast for a month","url":"https://world-weather.info/forecast/usa/new_york/may-2025/","encrypted_content":"Ev0DCioIAxgCIiQ3NmU4ZmI4OC1k...","page_age":null},...]}}

event: content_block_stop
data: {"type":"content_block_stop","index":2}

event: content_block_start
data: {"type":"content_block_start","index":3,"content_block":{"type":"text","text":""}}

event: content_block_delta
data: {"type":"content_block_delta","index":3,"delta":{"type":"text_delta","text":"Here's the current weather information for New York"}}

event: content_block_delta
data: {"type":"content_block_delta","index":3,"delta":{"type":"text_delta","text":" City:\n\n# Weather"}}

event: content_block_delta
data: {"type":"content_block_delta","index":3,"delta":{"type":"text_delta","text":" in New York City"}}

event: content_block_delta
data: {"type":"content_block_delta","index":3,"delta":{"type":"text_delta","text":"\n\n"}}

...

event: content_block_stop
data: {"type":"content_block_stop","index":17}

event: message_delta
data: {"type":"message_delta","delta":{"stop_reason":"end_turn","stop_sequence":null},"usage":{"input_tokens":10682,"cache_creation_input_tokens":0,"cache_read_input_tokens":0,"output_tokens":510,"server_tool_use":{"web_search_requests":1}}}

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

Recuperación de errores

Claude 4.5 y anteriores

Para modelos Claude 4.5 y anteriores, puedes recuperar una solicitud de transmisión que fue interrumpida debido a problemas de red, tiempos de espera u otros errores reanudando desde donde se interrumpió la transmisión. Este enfoque te ahorra de reprocesar toda la respuesta.

La estrategia básica de recuperación implica:

Capturar la respuesta parcial: Guarda todo el contenido que fue recibido exitosamente antes de que ocurriera el error
Construir una solicitud de continuación: Crea una nueva solicitud de API que incluya la respuesta parcial del asistente como el comienzo de un nuevo mensaje del asistente
Reanudar la transmisión: Continúa recibiendo el resto de la respuesta desde donde fue interrumpida

Claude 4.6

Para modelos Claude 4.6, debes agregar un mensaje de usuario que instruya al modelo a continuar desde donde se quedó. Por ejemplo:

Solicitud de ejemplo

Your previous response was interrupted and ended with [previous_response]. Continue from where you left off.

Mejores prácticas de recuperación de errores

Usar características del SDK: Aprovecha las capacidades integradas del SDK para acumulación de mensajes y manejo de errores
Manejar tipos de contenido: Ten en cuenta que los mensajes pueden contener múltiples bloques de contenido (text, tool_use, thinking). Los bloques de uso de herramientas y pensamiento extendido no pueden ser recuperados parcialmente. Puedes reanudar la transmisión desde el bloque de texto más reciente.

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Capacidades del modelo

Transmisión de Mensajes

Aprende cómo transmitir respuestas de mensajes de forma incremental usando eventos enviados por el servidor.

Al crear un Mensaje, puedes establecer "stream": true para transmitir la respuesta de forma incremental usando eventos enviados por el servidor (SSE).

Transmisión con SDKs

import anthropic

client = anthropic.Anthropic()

with client.messages.stream(
    max_tokens=1024,
    messages=[{"role": "user", "content": "Hello"}],
    model="claude-opus-4-6",
) as stream:
    for text in stream.text_stream:
        print(text, end="", flush=True)

Obtener el mensaje final sin manejar eventos

Tipos de eventos

Cada transmisión utiliza el siguiente flujo de eventos:

message_start: contiene un objeto Message con content vacío.
Una serie de bloques de contenido, cada uno de los cuales tiene un evento content_block_start, uno o más eventos content_block_delta, y un evento content_block_stop. Cada bloque de contenido tendrá un index que corresponde a su índice en el array final de content del Mensaje.
Uno o más eventos message_delta, indicando cambios de nivel superior al objeto final Message.
Un evento final message_stop.

Los conteos de tokens mostrados en el campo usage del evento message_delta son acumulativos.

Eventos ping

Los flujos de eventos también pueden incluir cualquier número de eventos ping.

Eventos de error

Ejemplo de error

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

Otros eventos

De conformidad con nuestra política de versionado, podemos agregar nuevos tipos de eventos, y tu código debe manejar tipos de eventos desconocidos de manera elegante.

Tipos de delta de bloque de contenido

Cada evento content_block_delta contiene un delta de un tipo que actualiza el bloque de content en un index dado.

Delta de texto

Un delta de bloque de contenido text se ve así:

Delta de texto

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

Delta JSON de entrada

Un delta de bloque de contenido tool_use se ve así:

Delta JSON de entrada

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

Delta de pensamiento

Un delta de pensamiento típico se ve así:

Delta de pensamiento

event: content_block_delta
data: {"type": "content_block_delta", "index": 0, "delta": {"type": "thinking_delta", "thinking": "I need to find the GCD of 1071 and 462 using the Euclidean algorithm.\n\n1071 = 2 × 462 + 147"}}

El delta de firma se ve así:

Delta de firma

event: content_block_delta
data: {"type": "content_block_delta", "index": 0, "delta": {"type": "signature_delta", "signature": "EqQBCgIYAhIM1gbcDa9GJwZA2b3hGgxBdjrkzLoky3dl1pkiMOYds..."}}

Respuesta de flujo HTTP completa

Una respuesta de transmisión se compone de:

Un evento message_start
Potencialmente múltiples bloques de contenido, cada uno de los cuales contiene:
- Un evento content_block_start
- Potencialmente múltiples eventos content_block_delta
- Un evento content_block_stop
Un evento message_delta
Un evento message_stop

También puede haber eventos ping dispersos a lo largo de la respuesta. Consulta Tipos de eventos para obtener más detalles sobre el formato.

Solicitud de transmisión básica

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-opus-4-6",
  "messages": [{"role": "user", "content": "Hello"}],
  "max_tokens": 256,
  "stream": true
}'

Respuesta

event: message_start
data: {"type": "message_start", "message": {"id": "msg_1nZdL29xx5MUA1yADyHTEsnR8uuvGzszyY", "type": "message", "role": "assistant", "content": [], "model": "claude-opus-4-6", "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"}

Solicitud de transmisión con uso de herramientas

El uso de herramientas soporta transmisión de grano fino para valores de parámetros. Habilítalo por herramienta con eager_input_streaming.

En esta solicitud, le pedimos a Claude que use una herramienta para decirnos el clima.

Respuesta

event: message_start
data: {"type":"message_start","message":{"id":"msg_014p7gG3wDgGV9EUtLvnow3U","type":"message","role":"assistant","model":"claude-opus-4-6","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"}

Solicitud de transmisión con pensamiento extendido

En esta solicitud, habilitamos el pensamiento extendido con transmisión para ver el razonamiento paso a paso de Claude.

Respuesta

event: message_start
data: {"type": "message_start", "message": {"id": "msg_01...", "type": "message", "role": "assistant", "content": [], "model": "claude-opus-4-6", "stop_reason": null, "stop_sequence": null}}

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

event: content_block_delta
data: {"type": "content_block_delta", "index": 0, "delta": {"type": "thinking_delta", "thinking": "I need to find the GCD of 1071 and 462 using the Euclidean algorithm.\n\n1071 = 2 × 462 + 147"}}

event: content_block_delta
data: {"type": "content_block_delta", "index": 0, "delta": {"type": "thinking_delta", "thinking": "\n462 = 3 × 147 + 21"}}

event: content_block_delta
data: {"type": "content_block_delta", "index": 0, "delta": {"type": "thinking_delta", "thinking": "\n147 = 7 × 21 + 0"}}

event: content_block_delta
data: {"type": "content_block_delta", "index": 0, "delta": {"type": "thinking_delta", "thinking": "\nThe remainder is 0, so GCD(1071, 462) = 21."}}

event: content_block_delta
data: {"type": "content_block_delta", "index": 0, "delta": {"type": "signature_delta", "signature": "EqQBCgIYAhIM1gbcDa9GJwZA2b3hGgxBdjrkzLoky3dl1pkiMOYds..."}}

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": "text", "text": ""}}

event: content_block_delta
data: {"type": "content_block_delta", "index": 1, "delta": {"type": "text_delta", "text": "The greatest common divisor of 1071 and 462 is **21**."}}

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

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

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

Solicitud de transmisión con uso de herramienta de búsqueda web

En esta solicitud, le pedimos a Claude que busque en la web información actual sobre el clima.

Respuesta

event: message_start
data: {"type":"message_start","message":{"id":"msg_01G...","type":"message","role":"assistant","model":"claude-opus-4-6","content":[],"stop_reason":null,"stop_sequence":null,"usage":{"input_tokens":2679,"cache_creation_input_tokens":0,"cache_read_input_tokens":0,"output_tokens":3}}}

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

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

event: content_block_delta
data: {"type":"content_block_delta","index":0,"delta":{"type":"text_delta","text":" the current weather in New York City for you"}}

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

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":"server_tool_use","id":"srvtoolu_014hJH82Qum7Td6UV8gDXThB","name":"web_search","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":"{\"query"}}

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":" \"weather"}}

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

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

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

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

event: content_block_start
data: {"type":"content_block_start","index":2,"content_block":{"type":"web_search_tool_result","tool_use_id":"srvtoolu_014hJH82Qum7Td6UV8gDXThB","content":[{"type":"web_search_result","title":"Weather in New York City in May 2025 (New York) - detailed Weather Forecast for a month","url":"https://world-weather.info/forecast/usa/new_york/may-2025/","encrypted_content":"Ev0DCioIAxgCIiQ3NmU4ZmI4OC1k...","page_age":null},...]}}

event: content_block_stop
data: {"type":"content_block_stop","index":2}

event: content_block_start
data: {"type":"content_block_start","index":3,"content_block":{"type":"text","text":""}}

event: content_block_delta
data: {"type":"content_block_delta","index":3,"delta":{"type":"text_delta","text":"Here's the current weather information for New York"}}

event: content_block_delta
data: {"type":"content_block_delta","index":3,"delta":{"type":"text_delta","text":" City:\n\n# Weather"}}

event: content_block_delta
data: {"type":"content_block_delta","index":3,"delta":{"type":"text_delta","text":" in New York City"}}

event: content_block_delta
data: {"type":"content_block_delta","index":3,"delta":{"type":"text_delta","text":"\n\n"}}

...

event: content_block_stop
data: {"type":"content_block_stop","index":17}

event: message_delta
data: {"type":"message_delta","delta":{"stop_reason":"end_turn","stop_sequence":null},"usage":{"input_tokens":10682,"cache_creation_input_tokens":0,"cache_read_input_tokens":0,"output_tokens":510,"server_tool_use":{"web_search_requests":1}}}

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

Recuperación de errores

Claude 4.5 y anteriores

La estrategia básica de recuperación implica:

Capturar la respuesta parcial: Guarda todo el contenido que fue recibido exitosamente antes de que ocurriera el error
Construir una solicitud de continuación: Crea una nueva solicitud de API que incluya la respuesta parcial del asistente como el comienzo de un nuevo mensaje del asistente
Reanudar la transmisión: Continúa recibiendo el resto de la respuesta desde donde fue interrumpida

Claude 4.6

Para modelos Claude 4.6, debes agregar un mensaje de usuario que instruya al modelo a continuar desde donde se quedó. Por ejemplo:

Solicitud de ejemplo

Your previous response was interrupted and ended with [previous_response]. Continue from where you left off.

Mejores prácticas de recuperación de errores

Usar características del SDK: Aprovecha las capacidades integradas del SDK para acumulación de mensajes y manejo de errores
Manejar tipos de contenido: Ten en cuenta que los mensajes pueden contener múltiples bloques de contenido (text, tool_use, thinking). Los bloques de uso de herramientas y pensamiento extendido no pueden ser recuperados parcialmente. Puedes reanudar la transmisión desde el bloque de texto más reciente.

Was this page helpful?

import anthropic

client = anthropic.Anthropic()

with client.messages.stream(
    max_tokens=128000,
    messages=[{"role": "user", "content": "Write a detailed analysis..."}],
    model="claude-opus-4-6",
) as stream:
    message = stream.get_final_message()

print(message.content[0].text)

  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-opus-4-6",
      "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
    }'

curl https://api.anthropic.com/v1/messages \
     --header "x-api-key: $ANTHROPIC_API_KEY" \
     --header "anthropic-version: 2023-06-01" \
     --header "content-type: application/json" \
     --data \
'{
    "model": "claude-opus-4-6",
    "max_tokens": 20000,
    "stream": true,
    "thinking": {
        "type": "enabled",
        "budget_tokens": 16000
    },
    "messages": [
        {
            "role": "user",
            "content": "What is the greatest common divisor of 1071 and 462?"
        }
    ]
}'

curl https://api.anthropic.com/v1/messages \
     --header "x-api-key: $ANTHROPIC_API_KEY" \
     --header "anthropic-version: 2023-06-01" \
     --header "content-type: application/json" \
     --data \
'{
    "model": "claude-opus-4-6",
    "max_tokens": 1024,
    "stream": true,
    "tools": [
        {
            "type": "web_search_20250305",
            "name": "web_search",
            "max_uses": 5
        }
    ],
    "messages": [
        {
            "role": "user",
            "content": "What is the weather like in New York City today?"
        }
    ]
}'