Stream responses in real-time

from claude_agent_sdk import query, ClaudeAgentOptions
from claude_agent_sdk.types import StreamEvent
import asyncio


async def stream_response():
    options = ClaudeAgentOptions(
        include_partial_messages=True,
        allowed_tools=["Bash", "Read"],
    )

    async for message in query(prompt="List the files in my project", options=options):
        if isinstance(message, StreamEvent):
            event = message.event
            if event.get("type") == "content_block_delta":
                delta = event.get("delta", {})
                if delta.get("type") == "text_delta":
                    print(delta.get("text", ""), end="", flush=True)


asyncio.run(stream_response())

import { query } from "@anthropic-ai/claude-agent-sdk";

for await (const message of query({
  prompt: "List the files in my project",
  options: {
    includePartialMessages: true,
    allowedTools: ["Bash", "Read"]
  }
})) {
  if (message.type === "stream_event") {
    const event = message.event;
    if (event.type === "content_block_delta") {
      if (event.delta.type === "text_delta") {
        process.stdout.write(event.delta.text);
      }
    }
  }
}

@dataclass
class StreamEvent:
    uuid: str  # Unique identifier for this event
    session_id: str  # Session identifier
    event: dict[str, Any]  # The raw Claude API stream event
    parent_tool_use_id: str | None  # Always None

type SDKPartialAssistantMessage = {
  type: "stream_event";
  event: BetaRawMessageStreamEvent; // From Anthropic SDK
  parent_tool_use_id: string | null;
  uuid: UUID;
  session_id: string;
  ttft_ms?: number; // Time to first token in ms, present only on message_start events
};

from claude_agent_sdk import query, ClaudeAgentOptions
from claude_agent_sdk.types import StreamEvent
import asyncio


async def stream_text():
    options = ClaudeAgentOptions(include_partial_messages=True)

    async for message in query(prompt="Explain how databases work", options=options):
        if isinstance(message, StreamEvent):
            event = message.event
            if event.get("type") == "content_block_delta":
                delta = event.get("delta", {})
                if delta.get("type") == "text_delta":
                    # Print each text chunk as it arrives
                    print(delta.get("text", ""), end="", flush=True)

    print()  # Final newline


asyncio.run(stream_text())

import { query } from "@anthropic-ai/claude-agent-sdk";

for await (const message of query({
  prompt: "Explain how databases work",
  options: { includePartialMessages: true }
})) {
  if (message.type === "stream_event") {
    const event = message.event;
    if (event.type === "content_block_delta" && event.delta.type === "text_delta") {
      process.stdout.write(event.delta.text);
    }
  }
}

console.log(); // Final newline

from claude_agent_sdk import query, ClaudeAgentOptions
from claude_agent_sdk.types import StreamEvent
import asyncio


async def stream_tool_calls():
    options = ClaudeAgentOptions(
        include_partial_messages=True,
        allowed_tools=["Read", "Bash"],
    )

    # Track the current tool and accumulate its input JSON
    current_tool = None
    tool_input = ""

    async for message in query(prompt="Read the README.md file", options=options):
        if isinstance(message, StreamEvent):
            event = message.event
            event_type = event.get("type")

            if event_type == "content_block_start":
                # New tool call is starting
                content_block = event.get("content_block", {})
                if content_block.get("type") == "tool_use":
                    current_tool = content_block.get("name")
                    tool_input = ""
                    print(f"Starting tool: {current_tool}")

            elif event_type == "content_block_delta":
                delta = event.get("delta", {})
                if delta.get("type") == "input_json_delta":
                    # Accumulate JSON input as it streams in
                    chunk = delta.get("partial_json", "")
                    tool_input += chunk
                    print(f"  Input chunk: {chunk}")

            elif event_type == "content_block_stop":
                # Tool call complete - show final input
                if current_tool:
                    print(f"Tool {current_tool} called with: {tool_input}")
                    current_tool = None


asyncio.run(stream_tool_calls())

import { query } from "@anthropic-ai/claude-agent-sdk";

// Track the current tool and accumulate its input JSON
let currentTool: string | null = null;
let toolInput = "";

for await (const message of query({
  prompt: "Read the README.md file",
  options: {
    includePartialMessages: true,
    allowedTools: ["Read", "Bash"]
  }
})) {
  if (message.type === "stream_event") {
    const event = message.event;

    if (event.type === "content_block_start") {
      // New tool call is starting
      if (event.content_block.type === "tool_use") {
        currentTool = event.content_block.name;
        toolInput = "";
        console.log(`Starting tool: ${currentTool}`);
      }
    } else if (event.type === "content_block_delta") {
      if (event.delta.type === "input_json_delta") {
        // Accumulate JSON input as it streams in
        const chunk = event.delta.partial_json;
        toolInput += chunk;
        console.log(`  Input chunk: ${chunk}`);
      }
    } else if (event.type === "content_block_stop") {
      // Tool call complete - show final input
      if (currentTool) {
        console.log(`Tool ${currentTool} called with: ${toolInput}`);
        currentTool = null;
      }
    }
  }
}

from claude_agent_sdk import query, ClaudeAgentOptions, ResultMessage
from claude_agent_sdk.types import StreamEvent
import asyncio
import sys


async def streaming_ui():
    options = ClaudeAgentOptions(
        include_partial_messages=True,
        allowed_tools=["Read", "Bash", "Grep"],
    )

    # Track whether we're currently in a tool call
    in_tool = False

    async for message in query(
        prompt="Find all TODO comments in the codebase", options=options
    ):
        if isinstance(message, StreamEvent):
            event = message.event
            event_type = event.get("type")

            if event_type == "content_block_start":
                content_block = event.get("content_block", {})
                if content_block.get("type") == "tool_use":
                    # Tool call is starting - show status indicator
                    tool_name = content_block.get("name")
                    print(f"\n[Using {tool_name}...]", end="", flush=True)
                    in_tool = True

            elif event_type == "content_block_delta":
                delta = event.get("delta", {})
                # Only stream text when not executing a tool
                if delta.get("type") == "text_delta" and not in_tool:
                    sys.stdout.write(delta.get("text", ""))
                    sys.stdout.flush()

            elif event_type == "content_block_stop":
                if in_tool:
                    # Tool call finished
                    print(" done", flush=True)
                    in_tool = False

        elif isinstance(message, ResultMessage):
            # Agent finished all work
            print(f"\n\n--- Complete ---")


asyncio.run(streaming_ui())

import { query } from "@anthropic-ai/claude-agent-sdk";

// Track whether we're currently in a tool call
let inTool = false;

for await (const message of query({
  prompt: "Find all TODO comments in the codebase",
  options: {
    includePartialMessages: true,
    allowedTools: ["Read", "Bash", "Grep"]
  }
})) {
  if (message.type === "stream_event") {
    const event = message.event;

    if (event.type === "content_block_start") {
      if (event.content_block.type === "tool_use") {
        // Tool call is starting - show status indicator
        process.stdout.write(`\n[Using ${event.content_block.name}...]`);
        inTool = true;
      }
    } else if (event.type === "content_block_delta") {
      // Only stream text when not executing a tool
      if (event.delta.type === "text_delta" && !inTool) {
        process.stdout.write(event.delta.text);
      }
    } else if (event.type === "content_block_stop") {
      if (inTool) {
        // Tool call finished
        console.log(" done");
        inTool = false;
      }
    }
  } else if (message.type === "result") {
    // Agent finished all work
    console.log("\n\n--- Complete ---");
  }
}