What's Changed

• test(proxy): add regression tests for vertex passthrough model names … by @michelligabriele in https://github.com/BerriAI/litellm/pull/19855
• fix: guardrails issues streaming-response regex by @Harshit28j in https://github.com/BerriAI/litellm/pull/19901
• fix: add fix for migration issue and and stable image by @Harshit28j in https://github.com/BerriAI/litellm/pull/19843
• fix: filter unsupported beta headers for AWS Bedrock Invoke API by @jayy-77 in https://github.com/BerriAI/litellm/pull/19877
• fix: allow tool_choice for Azure GPT-5 chat models by @jayy-77 in https://github.com/BerriAI/litellm/pull/19813
• fix: tool with antropic #19800 by @zifeo in https://github.com/BerriAI/litellm/pull/19805
• inspect BadRequestError after all other policy types by @demoray in https://github.com/BerriAI/litellm/pull/19878
• fix(main): use local tiktoken cache in lazy loading by @Chesars in https://github.com/BerriAI/litellm/pull/19774
• fix(gemini): subtract implicit cached tokens from text_tokens for correct cost calculation by @Chesars in https://github.com/BerriAI/litellm/pull/19775
• fix Prompt Studio history to load tools and system messages by @naaa760 in https://github.com/BerriAI/litellm/pull/19920