What's Changed

• Add OAuth authentication client for HTTPX by @ihrpr in #751
• fastmcp: allow passing Tool directly to FastMCP constructor by @vbarda in #699
• add auth client sse by @ihrpr in #760
• Change default binding from 0.0.0.0 to 127.0.0.1 to align with security recommendations by @ciccolo-anthropic in #738
• fix: Pass cursor parameter to server by @nbarbettini in #745

New Contributors

• @vbarda made their first contribution in #699
• @ciccolo-anthropic made their first contribution in #738

Full Changelog: v1.9.0...v1.9.1

Protocol Version Update

Now the latest protocol version for Python SDK is 2025-03-26

What's Changed

• Fix typo in authentication section of README by @mopg in #676
• fix: 204 is an acceptable response to DELETEing the session by @nbarbettini in #697
• Minor tweaks to README for Streamable HTTP by @evalstate in #690
• Properly infer prefix for SSE messages by @jlowin in #659
• Simple Auth Example to use shttp in addition to sse by @ihrpr in #695
• Create ClientSessionGroup for managing multiple session connections. by @mkeid in #639
• fix typo: server has get_context attribute instead of request_context. by @shimizukawa in #446
• docs: clarify LLM API configuration in mcp_simple_chatbot README by @ddltn in #487
• fix: Add checks and better error messages on server object for mcp run by @john0312 in #297
• Fix hanging on streams when stdio_client exiting by @LionNatsu in #559
• feat: add message to ProgressNotification by @aksheyd in #435
• Update CI configuration to support multiple OS environments by @DanielAvdar in #708
• feat: add cursor pagination support to all client list methods by @jerome3o-anthropic in #718
• Add example for stateless server with JSON response by @5enxia in #704
• Include server examples folder in pyright check by @ihrpr in #667
• Set 2025-03-26 as the latest protocol version by @ihrpr in #719
• Fix example for multiple stateless servers by @ihrpr in #720
• fix: Update @mcp.resource to use function documentation as default descrip… by @jingyugao in #489
• Add progress notification callback for client by @ihrpr in #721
• Servers to accept older versions of client by @ihrpr in #722

New Contributors

• @mopg made their first contribution in #676
• @nbarbettini made their first contribution in #697
• @jlowin made their first contribution in #659
• @mkeid made their first contribution in #639
• @shimizukawa made their first contribution in #446
• @ddltn made their first contribution in #487
• @LionNatsu made their first contribution in #559
• @aksheyd made their first contribution in #435
• @DanielAvdar made their first contribution in #708
• @5enxia made their first contribution in #704
• @jingyugao made their first contribution in #489

Full Changelog: v1.8.1...v1.9.0

What's Changed

• Fix streamable http sampling by @ihrpr in #693

Full Changelog: v1.8.0...v1.8.1

Streamable HTTP release

This is the first release supporting the new Streamable HTTP transport from protocol version 2025-03-26, which supersedes the SSE transport from protocol version 2024-11-05. 🎉
Please report any issues at https://github.com/modelcontextprotocol/python-sdk/issues

Other Changes

• Handle SSE Disconnects Properly by @akash329d in #612
• Add mount_path support for proper SSE endpoint routing with multiple FastMCP servers by @tim-watcha in #540
• docs: fix broken link to OAuthServerProvider in Authentication section of README by @samad-yar-khan in #651
• Fix the issue of get Authorization header fails during bearer auth by @yabea in #637
• Auth SSE simple example by @ihrpr in #610
• Fix: Use absolute path to uv executable in Claude Desktop config by @arcAman07 in #440
• Introduce a function to create a standard AsyncClient with options by @ihrpr in #655

New Contributors

• @akash329d made their first contribution in #612
• @tim-watcha made their first contribution in #540
• @samad-yar-khan made their first contribution in #651
• @yabea made their first contribution in #637
• @arcAman07 made their first contribution in #440

Full Changelog: v1.7.0...v1.8.0

Full Changelog: v1.7.0...v1.7.1

OAuth Support for servers

• Add support for serverside oauth by @praboud-ant in #255

Tool Annotations

• Add ToolAnnotations support in FastMCP and lowlevel servers by @bhosmer-ant in #482

Other changes

• Docs: Change README to correct pip installation command for MCP CLI support by @codingjenny in #394

• Fix python -m command error by @xuzexin-hz in #387

• Docs : Enhance README to suggest commands for creating a new UV project before adding mcp dependency. by @anupsajjan in #408

• Fix lifespan_context access example in README by @SigureMo in #437

• Match ruff version on CI and local by @Kludex in #471

• Fix @mcp.tool() Failing to Detect Context Argument When Type Variables Are Used in Context by @jkawamoto in #358

• Support custom client info throughout client APIs by @jerome3o-anthropic in #474

• Fix tests for Pydantic 2.11 by @medaminezghal in #465

• Move uvicorn import to usage by @danlapid in #502

• Python lint: Ruff rules for comprehensions and performance by @cclauss in #512

• Format files with ruff by @ihrpr in #562

• replace inefficient use of to_jsonable_python by @samuelcolvin in #545

• add a timeout arguments on per-request basis (as per MCP specifications) by @grll in #601

• add pytest-pretty dev dependency by @samuelcolvin in #546

• Properly clean up response streams in BaseSession by @bhosmer-ant in #515

New Contributors

• @codingjenny made their first contribution in #394
• @xuzexin-hz made their first contribution in #387
• @anupsajjan made their first contribution in #408
• @SigureMo made their first contribution in #437
• @jkawamoto made their first contribution in #358
• @medaminezghal made their first contribution in #465
• @danlapid made their first contribution in #502
• @cclauss made their first contribution in #512
• @grll made their first contribution in #601
• @bhosmer-ant made their first contribution in #482
• @praboud-ant made their first contribution in #255

Full Changelog: v1.6.0...v1.7.0

What's Changed

• Fix #201: Move incoming message stream from BaseSession to ServerSession by @dsp-ant in #325
• default log level info by @barnuri in #366
• ci: test multiple python versions by @Kludex in #345
• Add mkdocs by @Kludex in #367
• Fix #355: Fix type error with lifespan context by @dsp-ant in #368
• refactor: Make types.py strictly typechecked. by @dsp-ant in #336
• Fix typo in starlette import in README by @conorbranagan in #374
• Fixes to stdio_client to support Windows more robustly by @saqadri in #372
• Fix/base64 handling (Issue #342) by @evalstate in #343

New Contributors

• @barnuri made their first contribution in #366
• @conorbranagan made their first contribution in #374
• @saqadri made their first contribution in #372
• @evalstate made their first contribution in #343

Full Changelog: v1.5.0...v1.6.0

What's Changed

• Strict types on the client side by @Kludex in #285
• lint docs examples by @samuelcolvin in #286
• Avoid double JSON encoding/decoding by @Kludex in #287
• Improve readability of CLI help option by @Kludex in #295
• Option to mount SSE server to existing ASGI server by @comfuture in #312
• Add callback for logging message notification to client by @ihrpr in #314
• add cwd to StdioServerParameters by @samuelcolvin in #292
• docs(examples): fixing the prompts example by @Niraj-Fonseka in #318
• Add strict mode to pyright by @Kludex in #315
• Enhancement: make stderr of server subprocess configurable by @sheffler in #191
• Update init.py by @arthrod in #335
• Update types.py by @NinoRisteski in #243
• enable custom path of sse server by @elsejj in #246
• Use default environment even when env is provided by @maxguru in #327

New Contributors

• @samuelcolvin made their first contribution in #286
• @comfuture made their first contribution in #312
• @ihrpr made their first contribution in #314
• @Niraj-Fonseka made their first contribution in #318
• @arthrod made their first contribution in #335
• @NinoRisteski made their first contribution in #243
• @elsejj made their first contribution in #246
• @maxguru made their first contribution in #327

Full Changelog: v1.4.1...v1.4.2

What's Changed

• Update README to clarify installing mcp to project vs running mcp by @john0312 in #277
• Revert "refactor: reorganize message handling for better type safety and clarity" by @Kludex in #282

New Contributors

• @john0312 made their first contribution in #277

Full Changelog: v1.4.0...v1.4.1

What's Changed

• Update URL validation to allow file and other nonstandard schemas by @hmwildermuth in #207
• Add client handling for sampling, list roots, ping by @jerome3o-anthropic in #218
• Updated typing on request context for the server to use server session by @jerome3o-anthropic in #217
• Fix #177: Returning multiple tool results by @dsp-ant in #222
• Use proper generic for Context by @Kludex in #245
• Drop AbstractAsyncContextManager for proper type hint to BaseSession by @Kludex in #257
• Add ServerSessionT type var to Context by @Kludex in #271
• Create Client websocket.py by @calclavia in #179
• Close unclosed resources in the whole project by @Kludex in #267
• Add support for Linux configuration path in get_claude_config_path by @emsi in #270
• Release on GitHub release by @Kludex in #276
• Changed default log level to error by @Michaelzag in #258
• refactor: reorganize message handling for better type safety and clarity by @dsp-ant in #239

New Contributors

• @hmwildermuth made their first contribution in #207
• @Kludex made their first contribution in #245
• @calclavia made their first contribution in #179
• @emsi made their first contribution in #270
• @Michaelzag made their first contribution in #258

Full Changelog: v1.3.0...v1.4.0