OpenAI today began rolling out GPT-5.1: a new update to GPT-5 that refines conversational tone, improves instruction-following, and balances speed vs deep reasoning by automatically routing prompts to Instant or Thinking models. The update brings new personality options and reliability gains for structured tasks and is currently rolling out to paid tiers.

Three months after GPT-5’s debut, GPT-5.1 is a usability-focused update aimed at fixing long-standing complaints about robotic replies and flaky instruction-following. Rather than introduce radical new capabilities, OpenAI has tuned how the model communicates, reasons, and prioritises compute, a pragmatic step to improve everyday productivity for enterprise and consumer users alike.

GPT-5.1: warmth, personality and smarter routing

OpenAI says GPT-5.1 brings improvements to both its Instant and Thinking models: the two execution modes that power ChatGPT. The Instant model is tuned to sound “warmer, more intelligent, and better at following your instructions.” The update also adds new “personality” options (default, friendly, efficient, professional, candid, and quirky), giving users more control over tone.

On the reasoning front, GPT-5.1’s Thinking model has been tuned for efficiency: it processes simpler tasks faster, while taking more deliberate time on complex or analytical ones. That means quicker answers for routine prompts and deeper thinking where it counts — without users toggling settings manually.

OpenAI highlighted improved instruction adherence in tests: GPT-5.1 correctly obeyed prompts such as “reply in six words”, a task earlier versions often failed: a tangible win for structured writing, coding and education workflows.

Scaling Customer Experience with AI-Driven Support

• Customer support: Faster, friendlier instant replies for routine queries; the Thinking model can handle escalation paths that need multi-step reasoning.

• Developer productivity: Better adherence to instruction formats (code snippets, issue templates) reduces post-editing overhead.

• Research & legal: Complex, multi-step analysis benefits from the Thinking model’s slower, deeper passes.

• Content production: Personality controls let marketing and comms teams tune voice quickly for different audiences.

Rollout Strategy and Access Planning

GPT-5.1 is a meaningful UX and reliability upgrade, but it’s not a silver bullet. Key considerations for enterprise adopters:

• Reliability & hallucination risk: Improved instruction-following helps, but enterprises must still validate outputs for regulated or safety-critical uses.

• Cost and latency tradeoffs: Deeper reasoning uses more compute; organisations should weigh accuracy needs against cost.

• Customisation & guardrails: Personality options are helpful, but enterprises will want policy and safety controls tied to tone and content standards.

• Rollout & access: GPT-5.1 is rolling out to Pro, Plus, Go and Business plans first; free users get access later. Organisations should plan pilot programmes on paid tiers.

GPT-5.1 is a pragmatic, user-centric update that improves conversational quality and task reliability while introducing flexible tone control. For enterprises, the real test will be whether these refinements translate into measurable time savings, fewer human edits, and safer deployments in production workflows.