Field Notes: AI — March 2026

The month in one paragraph

March 2026 looked like platform cleanup at scale. OpenAI simplified model selection behavior in ChatGPT, retired GPT-5.1 there, rolled out GPT-5.4 mini, and expanded connected app posture across tools like Box, Notion, Linear, and Dropbox. The operator signal was clear: routing and integration quality mattered more than adding yet another model label.

Industry leader watch

• OpenAI platform: streamlined model strategy and pushed practical app-connectivity improvements.
• Anthropic/Gemini/open stacks: continued to compete, but buyers increasingly valued integration reliability and admin predictability.
• Tool ecosystem: became less about one flagship model and more about interoperability with existing work systems.

Tooling and workflow trends

• Model routing over model hype: teams optimized defaults, fallbacks, and policy-based selection.
• Connected workflow execution: app integrations became part of core "done" criteria for assistant features.
• KPI accountability: model/platform updates were judged by user and ops outcomes, not launch fanfare.

Dev-tool pulse

• OpenAI changes: GPT-5.1 retirement in ChatGPT, GPT-5.4 mini rollout, and connected-app integration updates.
• Ecosystem lesson: platform simplification plus app connectivity delivered more value than constant model menu expansion.

Operator math (TeX)

$$\Delta KPI = KPI_{\text{post-change}} - KPI_{\text{pre-change}}$$