Claude SDK for Python, which lets Python applications access the Claude API. It includes installation via pip and example code for creating messages and calling Claude models, with full API SDK documentation available on platform.claude.com.
Project status
- Actively maintained, with the last upstream push on 2026-08-27 and multiple SDK updates in August 2026, indicating ongoing development.
- Apparent update cadence is high, with frequent increments across 2026-07-24 to 2026-08-20 (roughly weekly to every few days), plus a major update on 2026-08-20.
AI summary generated
Recent updates
v1.2.0
v1.2.0 updates the SDK to use GA-shaped types for the beta files/skills namespaces, and removes some older beta header pinning behavior. It also hardens file upload and request signing (AWS and Bedrock), improves session event accumulation compatibility, and upgrades the tools file APIs to preserve exact bytes and support view_range reads over the size cap.
Featuresv1.1.0
Release v1.1.0 adds new beta API capabilities, including an `updates` thinking display mode and support for Organization API endpoints. It also adjusts tool runner behavior to keep execution going for `pause_turn`, alongside a set of internal refactors (including removing a legacy response API).
Featuresv1.0.0
v1.0.0 is a major release that upgrades the SDK from httpx to httpx2 across the client stack. The release notes only call out this upgrade (and to see MIGRATION.md), but the code diff shows additional API surface removals and behavior changes beyond just the dependency swap.
Breakingv0.125.0
v0.125.0 primarily introduces beta managed agents web search configuration and adds/updates logic for self-hosted sandbox memory in the environment worker. The code diff also expands the managed agents tool configuration surface area (new per-tool config models) and makes several self-hosted environment behavior and typing changes beyond what is mentioned in the release notes.
Featuresv0.124.0
v0.124.0 adds GA support for the Files and Skills APIs and introduces new computer use and browser use toolsets. The diff also shows a large expansion of generated type definitions related to browser tool configuration and state reporting.
Featuresv0.123.0
v0.123.0 adds several beta API capabilities around files, memory stores, and user/workspace context, and improves the client experience for reading workspace ID from response headers. It also includes reliability changes for tool execution, including longer tool-result retry behavior tied to the environment lease TTL, and adjustments for how sync tools run under the session runner. Finally, it removes support for the previously mentioned mid_conv_system content block.
BreakingFeaturesv0.122.0
Release v0.122.0 introduces an `output_behavior` option for Dreams, allowing the API to create a new destination memory store by default or update an existing store in place. The release also includes multiple bug fixes across Bedrock/streaming behavior, credential token exchange binding across `copy()`, and async AWS/Bedrock SigV4 signing to avoid blocking the event loop.
Featuresv0.121.0
v0.121.0 adds beta support for mid-conversation tool changes and extends managed agents with session budgets, an advisor roster entry, and pinned inference location. It also introduces new managed-agents usage and webhook event types related to budgets, and removes retired Claude Opus 4.1 model identifiers from the SDK mappings.
BreakingFeaturesv0.120.2
Release v0.120.2 adds compatibility for MCP SDK v2 while maintaining support for MCP SDK v1. The main code change introduces a field-name compatibility layer (camelCase to snake_case) so tool schemas, MIME types, and call results map correctly across MCP versions.
v0.120.1
v0.120.1 is a small patch release that primarily updates the SDK package version metadata and narrows the MCP extra dependency constraint. The only user-facing change in the diff is related to how the optional `mcp` extra resolves versions of the `mcp` dependency.
v0.120.0
v0.120.0 adds support for the claude-opus-5 model and introduces mid-conversation tool addition and removal blocks (along with tool_change related plumbing). It also expands the beta fallback credit behavior on the client side, including adding a server-side "default" option for fallbacks. The release notes cover these headline items, but the code diff contains several additional behavioral and request-shape changes that are not explicitly documented.
Featuresv0.119.0
v0.119.0 adds a new stop reason, `model_context_window_exceeded`, and updates the agent toolset to handle binary files when using the read/edit tooling. The code diff also reveals additional, more detailed changes to binary file handling behavior and configuration that are not fully covered by the release notes.
BreakingFeaturesv0.118.0
v0.118.0 adds Managed Agents support for configuring model effort, sending initial session events at session creation, and streaming thread event deltas. The release also includes a number of newly generated beta type models for effort levels and additional webhook event payloads.
Featuresv0.117.1
v0.117.1 primarily updates the SDK’s typed refusal metadata and fixes AWS client behavior around credentials handling. It also bumps and constrains a couple of HTTP-related development/runtime dependencies (notably http-snapshot and httpx_aiohttp).
Featuresv0.117.0
v0.117.0 adds new beta API support for “dreaming” and introduces support for MCP Tunnels. It also includes a credentials-focused fix intended to prevent credential material from appearing in traceback frame locals. The code diff reveals additional substantial functionality beyond what is described in the release notes.
SecurityFeaturesv0.116.0
v0.116.0 introduces support for the new beta header value agent-memory-2026-07-22 across beta memory store endpoints. In the code, this beta header default is swapped in where the previous managed-agents-2026-04-01 value was used.
Featuresv0.115.1
v0.115.1 primarily changes the SDK surface area for beta/webhook-related types and a few other parameter and schema details. The release notes only mention removing nonfunctional types, but the code diff shows several breaking changes to exported types and request/response typing.
v0.115.0
v0.115.0 adds Managed Agents “event delta” streaming (event_start and event_delta), along with agent overrides and reverse pagination support. It also expands beta webhook event typing to include additional event categories related to agents and deployments. Several new beta types and streaming helpers were added to support these capabilities.
Featuresv0.114.0
v0.114.0 adds support for the new model string "claude-sonnet-5" across the typed model parameters used by the SDK. It also adjusts agent file tool path resolution to permit absolute paths when, after canonicalization, they resolve inside the configured workdir. No other breaking API surface changes are evident from the provided diff.
Featuresv0.113.0
v0.113.0 adds new tool parameter types for the 20260318 web_fetch and web_search variants, and wires them into the SDK's exported type unions. It also updates the Messages token counting APIs to accept a user profile ID header, and includes a fix for an async count_tokens output_format/output_config merge issue.
Features