v0.2.143

Internal/Other Changes

• Updated bundled Claude CLI to version 2.1.238

---

PyPI: https://pypi.org/project/claude-agent-sdk/0.2.143/

pip install claude-agent-sdk==0.2.143

v0.2.142

Internal/Other Changes

• Updated bundled Claude CLI to version 2.1.237

---

PyPI: https://pypi.org/project/claude-agent-sdk/0.2.142/

pip install claude-agent-sdk==0.2.142

v0.2.141

Internal/Other Changes

• Updated bundled Claude CLI to version 2.1.236

---

PyPI: https://pypi.org/project/claude-agent-sdk/0.2.141/

pip install claude-agent-sdk==0.2.141

v0.2.140

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

v0.2.139

Internal/Other Changes

• Updated bundled Claude CLI to version 2.1.233

---

PyPI: https://pypi.org/project/claude-agent-sdk/0.2.139/

pip install claude-agent-sdk==0.2.139

v0.2.138

Internal/Other Changes

• Updated bundled Claude CLI to version 2.1.232

---

PyPI: https://pypi.org/project/claude-agent-sdk/0.2.138/

pip install claude-agent-sdk==0.2.138

v0.2.137

New Features

• ConversationResetMessage for conversation reset events: The SDK now surfaces the CLI's conversation_reset frame as a ConversationResetMessage dataclass, letting applications detect when a /clear or other transcript-discarding flow resets the conversation mid-session. Includes new_conversation_id, uuid, and session_id fields. This widens the Message union — code that exhaustively matches with assert_never will need updating (#1196)
• Message origin on UserMessage and ResultMessage: New origin: MessageOrigin | None field on UserMessage and ResultMessage surfaces why a turn was initiated — distinguishing application-submitted prompts ("human") from background-task notifications, scheduled triggers, peer messages, and other session-injected turns. New exported types: MessageOrigin, MessageOriginKind, TaskNotificationOriginSubkind (#1199)
• resume_session_at / resume_drops_turn options for truncating resume: ClaudeAgentOptions now supports resume_session_at (fork a session at an earlier transcript entry) and resume_drops_turn (validate that only entries from a specific turn are discarded). Enables safe rewind-to-before-last-prompt without silently dropping unobserved messages (#1198)

Bug Fixes

• Seed settings.json into temp config dir on SessionStore resume: Resuming from a SessionStore now copies settings.json and cowork_settings.json into the temporary config directory, preserving apiKeyHelper auth, user hooks, env vars, and permissions. Previously, hosts authenticating solely via apiKeyHelper would fail with "Not logged in" on resume (#1197)
• Improved error messages for failed resume: When the CLI rejects a resume (e.g. nonexistent session or resume_drops_turn guard failure), pending control requests like initialize() now receive the actual error text instead of a generic "Command failed with exit code 1" (#1198)

Internal/Other Changes

• Updated bundled Claude CLI to version 2.1.229

---

PyPI: https://pypi.org/project/claude-agent-sdk/0.2.137/

pip install claude-agent-sdk==0.2.137

v0.2.136

Internal/Other Changes

• Updated bundled Claude CLI to version 2.1.228

---

PyPI: https://pypi.org/project/claude-agent-sdk/0.2.136/

pip install claude-agent-sdk==0.2.136

v0.2.135

Internal/Other Changes

• Updated bundled Claude CLI to version 2.1.227

---

PyPI: https://pypi.org/project/claude-agent-sdk/0.2.135/

pip install claude-agent-sdk==0.2.135

v0.2.134

Internal/Other Changes

• Updated bundled Claude CLI to version 2.1.226

---

PyPI: https://pypi.org/project/claude-agent-sdk/0.2.134/

pip install claude-agent-sdk==0.2.134