OpenAI released GPT-5.2 on December 10, 2025, marking another volley in the AI model wars. With claims of 30% fewer factual errors and a perfect score on the AIME 2025 math benchmark, it's OpenAI's response to growing pressure from Google's Gemini 3 and Anthropic's Claude Opus 4.5. Here's everything you need to know.

What's New in GPT-5.2

According to OpenAI's official announcement, GPT-5.2 brings several key improvements over GPT-5.1:

  • 30% fewer factual errors - GPT-5.2 Thinking produces errors 30% less frequently than GPT-5.1
  • Perfect AIME 2025 score - 100% on challenging mathematics problems (AIME is the American Invitational Mathematics Examination)
  • Improved reasoning - GPT-5.2 Thinking outperformed GPT-5.1 across 10 key benchmarks highlighted by OpenAI

The release comes amid what CNBC reports as a "code red" situation at OpenAI. Sam Altman reportedly sent a memo to staff outlining an urgent effort to improve ChatGPT as competitors gain ground.

Why OpenAI Is Under Pressure

Despite ChatGPT's dominance with over 800 million weekly users, OpenAI faces increasingly stiff competition:

  • Google's Gemini 3 launched November 18, 2025 and topped multiple industry benchmarks
  • Anthropic's Claude Opus 4.5 released November 24, 2025 with 80.9% on SWE-bench Verified - the highest coding score ever
  • Gemini and Grok are leading AI chatbots in user growth, according to Comscore

According to Artificial Analysis, an independent AI benchmarking organization, Google's Gemini 3 Pro briefly claimed the top spot on their global AI index - a significant shift in the competitive landscape.

Current Model Comparison: December 2025

Coding Performance

For developers and businesses building AI-powered applications, coding capability remains the key differentiator:

Model SWE-bench Verified Release Date
Claude Opus 4.5 80.9% Nov 24, 2025
GPT-5.1-Codex-Max 77.9% Nov 19, 2025
Gemini 3 Pro 76.2% Nov 18, 2025

Key insight: Claude Opus 4.5 remains the coding champion with 80.9% on SWE-bench Verified. According to Anthropic, Opus 4.5 "scored higher on our most challenging internal engineering assessment than any human job candidate in the company's history."

Reasoning Performance

On Humanity's Last Exam - 2,500 expert-level questions designed to push AI to its limits - the standings as of late November were:

Model Score
Gemini 3 Pro (Deep Think) 41.0%
Gemini 3 Pro (Standard) 37.5%
GPT-5 35.2%

GPT-5.2's Humanity's Last Exam scores haven't been independently verified yet, but OpenAI claims improvements across reasoning benchmarks.

Pricing Comparison

Cost remains a major factor for businesses choosing between models:

Model Input (per 1M tokens) Output (per 1M tokens)
GPT-5.1 $1.25 $10.00
Gemini 3 Pro (≤200K) $2.00 $12.00
Claude Opus 4.5 $5.00 $25.00

GPT-5.1 remains the most affordable frontier model. Claude Opus 4.5 is 4x more expensive but delivers the best coding performance.

The Agentic AI Foundation: A New Chapter

In a surprising move, OpenAI, Anthropic, and Block (formerly Square) announced the formation of the Agentic AI Foundation (AAIF) on December 9, 2025. According to TechCrunch, this Linux Foundation-backed initiative aims to prevent AI agents from "splintering into a mess of incompatible, locked-down products."

Key contributions include:

  • Anthropic: Donating MCP (Model Context Protocol)
  • Block: Contributing Goose
  • OpenAI: Bringing AGENTS.md

Platinum members include Amazon Web Services, Bloomberg, Cloudflare, Google, and Microsoft. This collaboration suggests the major players recognize that standardization benefits everyone.

Context Windows: The Memory Battle

Model Context Window
Gemini 3 Pro 1 million tokens
GPT-5.1 (API) 400K tokens
Claude Opus 4.5 264K tokens

Gemini 3 Pro's 1 million token context window remains unmatched - useful for analyzing entire codebases or processing very long documents.

Which Model Should You Choose in December 2025?

Choose GPT-5.2 If:

  • Budget is a priority (most affordable frontier model)
  • You need personality customization (8 preset personalities)
  • Factual accuracy is critical (30% fewer errors claimed)
  • You want the largest ecosystem of plugins and integrations

Choose Gemini 3 Pro If:

  • You need massive context (1 million tokens)
  • Reasoning performance matters most (tops Humanity's Last Exam)
  • You want Generative UI capabilities
  • You're already in Google's ecosystem

Choose Claude Opus 4.5 If:

  • Coding quality is paramount (80.9% SWE-bench - unmatched)
  • Security is critical (best prompt injection resistance)
  • You're building autonomous agents
  • Enterprise reliability matters

The Bottom Line

GPT-5.2 is a solid incremental improvement that addresses some of GPT-5.1's weaknesses, particularly around factual accuracy. However, it doesn't dramatically change the competitive landscape:

  • For coding: Claude Opus 4.5 remains king
  • For reasoning: Gemini 3 Pro leads
  • For value: GPT-5.1/5.2 offers the best price-to-performance
  • For context: Gemini 3 Pro's 1M tokens is unmatched

The AI model race shows no signs of slowing. With the Agentic AI Foundation forming and all three companies investing billions in infrastructure, 2026 promises even more competition.

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