Crate claude_code 

Claude Code SDK for Rust

A Rust implementation of the Claude Code Agent SDK, providing programmatic access to Claude Code as a subprocess. This crate is a port of the official Python Claude Code SDK.

Overview

The SDK provides two main ways to interact with Claude Code:

• query() — Creates a new session for each interaction. Best for one-off tasks, independent operations, and simple automation scripts.
• ClaudeSdkClient — Maintains a conversation session across multiple exchanges. Best for continuing conversations, follow-up questions, interactive applications, and session lifecycle management.

Quick Comparison

Feature	query()	ClaudeSdkClient
Session	New session each time	Reuses same session
Conversation	Single exchange	Multiple exchanges in same context
Connection	Managed automatically	Manual control
Interrupts	Not supported	Supported
Custom Tools	Supported	Supported
Use Case	One-off tasks	Continuous conversations

Example — One-off query

use claude_code::{query, ClaudeAgentOptions, InputPrompt, Message};

let messages = query(
    InputPrompt::Text("What is 2 + 2?".to_string()),
    Some(ClaudeAgentOptions {
        permission_mode: Some(claude_code::PermissionMode::BypassPermissions),
        ..Default::default()
    }),
    None,
).await?;

for msg in messages {
    if let Message::Assistant(assistant) = msg {
        println!("{:?}", assistant.content);
    }
}

Example — Continuous conversation with ClaudeSdkClient

use claude_code::{ClaudeSdkClient, InputPrompt};

let mut client = ClaudeSdkClient::new(None, None);
client.connect(None).await?;

// First question
client.query(InputPrompt::Text("What's the capital of France?".into()), "default").await?;
let response = client.receive_response().await?;

// Follow-up — session retains context
client.query(InputPrompt::Text("What's the population of that city?".into()), "default").await?;
let follow_up = client.receive_response().await?;

client.disconnect().await?;

Re-exports

pub use client::ClaudeSdkClient;

pub use client::InputPrompt;

pub use errors::CLIConnectionError;

pub use errors::CLIJSONDecodeError;

pub use errors::CLINotFoundError;

pub use errors::ClaudeSDKError;

pub use errors::Error;

pub use errors::MessageParseError;

pub use errors::ProcessError;

pub use errors::Result;

pub use message_parser::parse_message;

pub use query::Query;

pub use query::handle_sdk_mcp_request;

pub use query_fn::query;

pub use query_fn::query_from_stream;

pub use query_fn::query_stream;

pub use query_fn::query_stream_from_stream;

pub use sdk_mcp::McpSdkServer;

pub use sdk_mcp::SdkMcpTool;

pub use sdk_mcp::create_sdk_mcp_server;

pub use sdk_mcp::tool;

pub use transport::subprocess_cli::DEFAULT_MAX_BUFFER_SIZE;

pub use transport::subprocess_cli::JsonStreamBuffer;

pub use transport::subprocess_cli::Prompt;

pub use transport::subprocess_cli::SubprocessCliTransport;

pub use transport::SplitAdapter;

pub use transport::Transport;

pub use transport::TransportCloseHandle;

pub use transport::TransportFactory;

pub use transport::TransportReader;

pub use transport::TransportSplitResult;

pub use transport::TransportWriter;

pub use transport::split_with_adapter;

pub use types::AgentDefinition;

pub use types::AssistantMessage;

pub use types::ClaudeAgentOptions;

pub use types::ContentBlock;

pub use types::HookCallback;

pub use types::HookContext;

pub use types::HookInput;

pub use types::HookJSONOutput;

pub use types::HookMatcher;

pub use types::McpHttpServerConfig;

pub use types::McpSSEServerConfig;

pub use types::McpSdkServerConfig;

pub use types::McpServerConfig;

pub use types::McpServersOption;

pub use types::McpStdioServerConfig;

pub use types::Message;

pub use types::PermissionMode;

pub use types::PermissionResult;

pub use types::PermissionResultAllow;

pub use types::PermissionResultDeny;

pub use types::PermissionUpdate;

pub use types::ResultMessage;

pub use types::SandboxIgnoreViolations;

pub use types::SandboxNetworkConfig;

pub use types::SandboxSettings;

pub use types::SdkPluginConfig;

pub use types::SettingSource;

pub use types::StderrCallback;

pub use types::StreamEvent;

pub use types::SystemMessage;

pub use types::SystemPrompt;

pub use types::SystemPromptPreset;

pub use types::TextBlock;

pub use types::ThinkingBlock;

pub use types::ThinkingConfig;

pub use types::ToolAnnotations;

pub use types::ToolPermissionContext;

pub use types::ToolResultBlock;

pub use types::ToolUseBlock;

pub use types::ToolsOption;

pub use types::ToolsPreset;

pub use types::UserContent;

pub use types::UserMessage;

Modules

client

Session-based client for multi-turn interactions with Claude Code.

errors

Error types for the Claude Code SDK.

internal_client

Internal client for executing single-query sessions.

message_parser

JSON message parser for the Claude Code CLI protocol.

query

Core query/session management for Claude Code communication.

query_fn

Convenience function for one-off Claude Code queries.

sdk_mcp

In-process MCP (Model Context Protocol) server support.

transport

Transport layer abstraction for CLI communication.

types

Core data types for the Claude Code SDK.

Constants

SDK_VERSION

The version of the Claude Code Rust SDK, sourced from Cargo.toml.