OpenAI launched GPT-5.5 as its new flagship model for "real work and powering agents," immediately available in ChatGPT and Codex but with delayed API access due to enhanced safety requirements. The model features improved token efficiency and supports longer multi-step execution with tool use and self-checking. Pricing is set at $5/$30 per million tokens for GPT-5.5 and $30/$180 for GPT-5.5 Pro, roughly double the cost of GPT-5.4.

The release includes significant Codex upgrades such as browser control, document handling, and OS-wide dictation. Early reactions are mixed but generally positive, noting improvements in coding and long-horizon tasks, though some benchmarks show incremental gains and hallucination issues persist. Third-party ecosystem support like Hermes Agent integration appeared quickly.