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Changelog

Pin SDK versions in production.

2026-09-27: Free preview

  • Jein opens as a free preview: a free account with 500,000 free input tokens a month, no credit card and no payment details.
  • Jev-compatible API: POST /v1/systemone and GET /v1/models take the same requests as Jev, so the Jev SDKs work with a changed base URL and key.
  • Two pinned checkpoints: English laya-0.3.20 and laya-multilingual-0.3.20. laya-latest and the Jev aliases route non-English state text to the multilingual checkpoint; responses name the model that ran and set x-jein-routed-language. Pin laya-0.3.20 to stay on English.
  • GET /v1/models lists every accepted model name, including the Jev compatibility aliases.
  • A Sandbox in the dashboard runs requests without code.