What's Changed

Optimizers

• Validate GEPA metric signature by @okhat in https://github.com/stanfordnlp/dspy/pull/8697
• MIPROv2: Warn on deprecated requires_permission_to_run by @TomeHirata in https://github.com/stanfordnlp/dspy/pull/8635
• Fix mlflow<>gepa by @LakshyAAAgrawal @chenmoneygithub in https://github.com/stanfordnlp/dspy/pull/8691, https://github.com/stanfordnlp/dspy/pull/8696

LMs & Adapters

• Allow custom chunk type in stream by @chenmoneygithub in https://github.com/stanfordnlp/dspy/pull/8679
• Support OpenAI response api in LM by @TomeHirata in https://github.com/stanfordnlp/dspy/pull/8692
• Fix issues in BAMLAdapter by @chenmoneygithub in https://github.com/stanfordnlp/dspy/pull/8654
• Handle gpt-5-nano as reasoning model by @okhat in https://github.com/stanfordnlp/dspy/pull/8693

Maintenance

• Add test to ensure saving/loading backward compatibility by @chenmoneygithub in https://github.com/stanfordnlp/dspy/pull/8680
• Add type hints for Module.call and Module.acall to return Prediction by @jsummerfield in https://github.com/stanfordnlp/dspy/pull/8681
• chore: fix error message: gpt-5o -> gpt-5 by @Shangyint in https://github.com/stanfordnlp/dspy/pull/8686