anthropics/claude-agent-sdk-python v0.2.140

on GitHub

New Features

• MCP 2.x support for in-process SDK MCP servers: The SDK now supports mcp 2.x alongside 1.x (dependency widened to mcp>=1.23.0,<3.0.0). In-process servers are served over mcp's own in-memory transport instead of hand-rolled JSON-RPC dispatch, so hand-built mcp.server.Server instances now work at full fidelity — resources, prompts, and all result content types reach the CLI verbatim. Tool cancellation on interrupt is supported on mcp 2.x. claude_agent_sdk.ToolAnnotations accepts both camelCase and snake_case hint names on every mcp version (#1218)
• forward_subagent_text option: New forward_subagent_text boolean on ClaudeAgentOptions forwards a subagent's text and thinking blocks as messages in the stream, so consumers can render the full nested transcript. Matches the TypeScript SDK's forwardSubagentText (#1206)
• ResultError exception with structured error payload: When the CLI exits after a terminal error result, the SDK now raises ResultError (a subclass of ProcessError) instead of a bare "exit code 1" error. Carries subtype, errors, result, api_error_status, terminal_reason, session_id, and the raw data dict so callers can branch on failure reason without string matching. New exported types: ResultError (#1205)
• can_use_tool callback support for query() and string prompts: The can_use_tool permission callback now works with string prompts (not just ClaudeSDKClient), and stdin is kept open so the CLI can send permission requests over the control protocol (#1204)

Bug Fixes

• Recover parent_tool_use_id when reading subagent transcripts: get_subagent_messages() and get_subagent_messages_from_store() now recover the parent_tool_use_id from the subagent's metadata, linking each subagent's messages to the Agent tool_use block in the parent session. SessionMessage also gains a parent_agent_id field for the spawning agent's id (#1207)

Internal/Other Changes

• Updated bundled Claude CLI to version 2.1.235

PyPI: https://pypi.org/project/claude-agent-sdk/0.2.140/

pip install claude-agent-sdk==0.2.140