Overview
Open Responses is launching as a vendor-neutral JSON API specification for communicating with hosted LLMs, based on OpenAI’s Responses API. This standardizes how different AI tools can talk to each other, with major launch partners including OpenRouter, Hugging Face, LM Studio, vLLM, Ollama and Vercel already committed.
Key Facts
- Based on OpenAI’s newer Responses API rather than Chat Completions - supports advanced features like reasoning traces from the start
- Launch partners include OpenRouter, Hugging Face, LM Studio, vLLM, Ollama and Vercel - covers nearly every major model hosting and serving platform
- OpenRouter participation alone means - access to almost every existing LLM model through one standardized interface
- Includes compliance testing tools and React app - developers can verify their implementations work correctly
- Missing client-side conformance testing - gap in ensuring client libraries handle all specification details properly
Why It Matters
This matters because it could end vendor lock-in for AI applications - developers won’t need to rewrite code when switching between different LLM providers, and the ecosystem can build interoperable tools instead of proprietary silos.