What's Changed

Features & Enhancements

• Tooling / APIs

  • Add ToolCall.execute for smoother tool execution (#8825, @TomeHirata)

• Networking / Headers

  • Add DSPy User-Agent header (#8887, @TomeHirata)
  • Update headers when specified (#8893, @TomeHirata)

• Arbor / RL

  • Arbor GRPO Sync Update (#8939, @Ziems)

Bug Fixes & Reliability

• Streaming / Buffers

  • Fix chunk loss in long streaming with native response field (#8881, @TomeHirata)
  • Make the buffer condition more precise (#8907, @TomeHirata)
  • fix: add fallback on missing end marker during streaming (#8890, @enitrat)

• Adapters

  • fix(JSONAdapter): escape logic when JSON mode but no structured outputs (#8871, @isaacbmiller)
  • fix: XML adapter markers (#8876, @enitrat)
  • Fix test_xml_adapter_full_prompt (#8904, @TomeHirata)

• Responses / APIs

  • Fix responses API (#8880, @chenmoneygithub)
  • Fix response_format handling for responses API (#8911, @TomeHirata)

• Core / LM

  • Fix error handling in dspy parallel (#8860, @TomeHirata)
  • fix(LM): default temperature and max_tokens to None (#8908, @isaacbmiller)

• MIPRO

  • fix(MIPROv2): select between task_model and prompt_model (#8877, @isaacbmiller)

Security & Privacy

• Exclude API keys from saved programs (#8941, @Copilot)

Refactors & Maintenance

• Refactor URL construction in ArborReinforceJob to use urljoin (#8951, @Ziems)
• Update type hint of ClientSession (#8894, @TomeHirata)
• Long line in function signature (style) (#8914, @chenmoneygithub)
• Fix lint of LM (#8884, @chenmoneygithub)

Documentation

• Add Learn MCP page (#8903, @TomeHirata)
• Fix MIPRO paper link in RAG tutorial (#8937, @TomeHirata)
• [Docstring] Add docstring for Adapter (#8915, @chenmoneygithub)
• [Docs] Google-style docstrings for dspy/primitives/example Example class (#8949, @Davshiv20)
• [Docs] Google-style docstrings for Signature.prepend/append/insert/delete (#8945, @gnetsanet)
• Better tutorial sidebar—do not auto-expand all tutorials (#8912, @chenmoneygithub)

Tests & Stability

• Deflake the real LM test (#8924, @chenmoneygithub)

New Contributors

• @enitrat made their first contribution in https://github.com/stanfordnlp/dspy/pull/8890
• @Copilot made their first contribution in https://github.com/stanfordnlp/dspy/pull/8941
• @Davshiv20 made their first contribution in https://github.com/stanfordnlp/dspy/pull/8949
• @gnetsanet made their first contribution in https://github.com/stanfordnlp/dspy/pull/8945

Full Changelog: https://github.com/stanfordnlp/dspy/compare/3.0.4b1...3.0.4b2