GPT Models
tiktoken 0.8.1 Ships o200k_harmony Encoding for GPT-5.5
Reported: April 11, 2026 — tiktoken 0.8.1 When OpenAI ships a new model, tiktoken typically follows with a release that registers the model’s encoding and.
GPT-5.4 Structured Outputs Broke My Pydantic Schemas
The additionalProperties trap in GPT-5.4’s April refresh The April 2026 GPT-5.4 snapshot tightened how the OpenAI API enforces JSON Schema on the.
The Democratization of Reasoning: How Emerging Open Source Models Are Rivaling GPT-5 Performance
Introduction The landscape of artificial intelligence is undergoing a seismic shift, marking a pivotal moment in GPT Open Source News.