ChatGPT 5.5 "Spud" just dropped... did it destroy Opus 4.7?

Join AI Foundations: https://www.skool.com/ai-foundations Work with us: https://aifoundations.io/apply Our FREE Resources: https://aifoundations.io/resources GPT 5.5 launched April 23rd 2026, and this is the honest review with benchmarks and a live test in Codex against Claude Opus 4.7. The video covers the OpenAI blog post highlights, the benchmarks where GPT 5.5 wins (long context, terminal, ARC AGI 2, CyberGym), the benchmarks where Opus 4.7 still wins (SWE-Bench Pro, MCP Atlas, Humanity's Last Exam without tools), who each model is actually for, and a hands-on test that spawns three Codex background agents in parallel to build a dungeon game, a landing page, and an artificial life simulation in under 12 minutes. GPT 5.5 is OpenAI's new flagship model, available in ChatGPT, Codex, and the OpenAI API. It targets four verticals: agentic coding, computer use, knowledge work, and early scientific research. OpenAI claims higher quality outputs with significantly fewer tokens and fewer retries, and senior engineers report it is noticeably stronger than GPT 5.4 and Claude 4.7 at reasoning, autonomy, and catching issues in advance. The model scored 74% on a long-context benchmark versus 32.2% for the next model, leads on Terminal Bench and CyberGym, and was used with a custom harness to discover a proof of a long-standing asymptotic fact about off-diagonal Ramsey numbers, later verified in Lean. Claude Opus 4.7 still leads on SWE-Bench Pro, Finance Agent V1.1, MCP Atlas, and Humanity's Last Exam without tools. The summary: GPT 5.5 is the long-context, terminal, and hardest-reasoning model. Opus 4.7 is the production code, MCP agent, and reasoning-without-tools model. Chapters 0:00 GPT 5.5 Just Dropped: Initial Reaction 1:09 GPT 5.5 Launches April 23rd 2026 1:35 What GPT 5.5 Excels At 1:45 OpenAI's Move Into Knowledge Work And Cowork's Territory 3:22 Higher Quality Outputs With Fewer Tokens 4:00 The Demo Apps Built With GPT 5.5 4:59 GPT 5.5 vs GPT 5.4 vs Claude 4.7: Engineer Reviews 5:54 Why Coding Harnesses Beat Cowork Style Tools 7:44 Scientific Research And The Co-Scientist Claim 9:17 The Ramsey Numbers Proof That Knocked My Socks Off 10:45 Benchmarks Where GPT 5.5 Wins 12:41 Benchmarks Where Opus 4.7 Still Wins 14:07 Who Each Model Is Actually For 15:19 Final Summary: GPT 5.5 vs Opus 4.7 15:53 Live Test In Codex With GPT 5.5 16:44 Spawning Three Background Agents In Parallel 19:27 Reviewing The Three Projects: Game, Landing Page, Sim 20:06 Playing The Dungeon Game 20:47 Final Verdict On GPT 5.5 #chatgpt #codex #claude