OpenAI has launched GPT-5 as the new default model for ChatGPT users while simultaneously releasing AgentKit, a comprehensive enterprise platform for building and deploying AI agents. The dual announcement represents OpenAI's most significant enterprise-focused product launch since GPT-4, directly addressing the growing demand for integrated AI agent development tools.
GPT-5 Becomes Default ChatGPT Model
GPT-5 is now rolling out as the default model for all ChatGPT users, replacing GPT-4o for signed-in users across Plus, Pro, Team, and Free tiers. Enterprise and Education users will receive access next week.
The new model introduces three operational modes:
- Auto Mode: Automatically selects optimal performance settings for most users
- Fast Mode: Prioritizes rapid response times for time-sensitive tasks
- Thinking Mode: Enables deeper reasoning for complex problem-solving
ChatGPT Plus users receive 3,000 messages per week with GPT-5 Thinking, with additional capacity available through GPT-5 Thinking mini after reaching limits.
Enterprise Model Access Expansion
Paid users can now toggle "Show additional models" in ChatGPT web settings to access advanced models including o3, o4-mini, 4.1, and GPT-5 Thinking mini. The o3 reasoning model is scheduled for release in January 2025.
AgentKit: Complete AI Agent Development Platform
AgentKit represents OpenAI's answer to enterprise demands for integrated agent development tools. Until now, building AI agents required "juggling fragmented tools," according to OpenAI's announcement.
Core AgentKit Components
Agent Builder enables visual workflow design, allowing developers to create complex agent behaviors through drag-and-drop interfaces rather than traditional coding approaches.
Connector Registry provides pre-built integrations with enterprise systems, databases, and APIs, eliminating the need for custom integration development in many cases.
The platform enables developers to "embed agentic UIs faster using new building blocks," significantly reducing development time for enterprise AI implementations.
Real-World Enterprise Implementation
OpenAI demonstrated AgentKit capabilities through Ramp's procurement agent implementation. The system allows employees to type requests like "I need five more ChatGPT business seats," and the agent automatically:
- Parses the natural language request
- Checks against company expense policies
- Completes procurement processes that previously took weeks
- Delivers results in minutes rather than days
Enterprise AI Agent Market Response
The AgentKit launch directly addresses growing enterprise frustration with AI as "a simple information retrieval tool." Companies increasingly demand AI systems that function as "productivity engines that automate complex business processes."
OpenAI's move comes as enterprises struggle with fragmented AI implementations. Recent surveys indicate that while 92% of companies plan to increase AI investments over the next three years, only 1% consider themselves "mature" in AI deployment.
Market Timing and Competition
The launch positions OpenAI to compete directly with enterprise-focused AI platforms from Salesforce, Microsoft, and Google. AgentKit's visual workflow approach mirrors successful enterprise automation platforms while adding advanced AI capabilities.
Technical Architecture Improvements
AgentKit addresses common enterprise AI challenges:
- Integration Complexity: Pre-built connectors eliminate months of custom development
- Workflow Design: Visual tools enable business users to modify agent behaviors
- Scalability: Cloud-native architecture supports enterprise-level deployments
- Security: Enterprise-grade security controls and compliance features
Industry Impact and Workforce Implications
The combined GPT-5 and AgentKit launch accelerates AI agent adoption across enterprise workflows. McKinsey research estimates AI could add $4.4 trillion in productivity growth potential through corporate automation.
Early implementations suggest significant workforce transformation potential. Ramp's procurement automation example demonstrates how multi-week processes can be reduced to minutes, potentially affecting procurement, compliance, and administrative roles across industries.
Enterprise Adoption Barriers
Despite advanced capabilities, significant implementation challenges remain:
- 77% of organizations rate their data quality as average, poor, or very poor for AI readiness
- Only 3% of departments have achieved advanced automation via AI/ML technologies
- Integration with legacy enterprise systems requires extensive testing and validation
OpenAI's platform approach attempts to address these challenges through standardized integration tools and visual workflow design, potentially reducing technical barriers to enterprise AI agent deployment.
Strategic Market Positioning
The AgentKit platform represents OpenAI's evolution from AI model provider to comprehensive enterprise software vendor. The move directly competes with established enterprise automation platforms while offering superior AI capabilities.
For enterprises, the launch provides a potential solution to the "AI experimentation to production" gap that has limited widespread adoption. The platform's focus on visual design and pre-built integrations could accelerate enterprise AI agent deployment timelines from months to weeks.
The dual release of GPT-5 and AgentKit signals OpenAI's commitment to enterprise market leadership as AI agents transition from experimental tools to core business productivity platforms.