Does GPT-5 Codex live up to the hype?

Today we are testing GPT-5 codex to see if it is really the best coding agent on the market. ANNOUNCEMENT If you like these tests, check out Jakob's new creativity-focused benchmark at https://vibebench.ai PROMPTS Planet https://featurecrew.io/prompts/planet/v1.txt https://featurecrew.io/prompts/planet/v2.txt City https://featurecrew.io/prompts/city/v1.txt https://featurecrew.io/prompts/city/v2.txt Dungeon https://featurecrew.io/prompts/dungeon/v1.txt https://featurecrew.io/prompts/dungeon/v2.txt

Channel: The Feature CrewGenerated by anonymousDuration: 15mPublished Sep 22, 2025
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Video Chapters

Original Output

0:00 Journey into the future: Unpacking GPT-5 Codex's capabilities.
0:58 First contact: Witnessing the birth of a procedural world.
3:00 A leap in design: Our planet now breathes with atmosphere and biomes.
4:03 Lessons from the cosmos: The procedural planet project concludes.
4:43 Blueprint for tomorrow: Embarking on the city generation challenge.
5:02 Urban chaos or genius? Our first city takes shape, with surprises.
7:07 The metropolis awakens: Behold a vibrant, organized cityscape.
9:25 Into the unknown: Charting a course for our dungeon crawler adventure.
12:03 Victory! Our procedural dungeon is ready for brave adventurers.
13:11 The final verdict: Reflecting on Codex's role as a coding companion.

Timestamps by StampBot 🤖

Unprocessed Timestamp Content

0:00 Welcome to the future crew, let's talk GPT-5 Codex
0:15 Getting started with the 3D planet generation test, single HTML file
0:58 Behold, the first procedural planet, not quite Earth, but it rotates
1:42 Running parallel tests: the power of asynchronous code generation
2:39 The multi-file planet: a slightly more organized, still very blue world
3:00 Improved planet with clearer atmosphere, distinct land, and water biomes
4:03 Planet generation conclusion: better water, messed up heights, but it works
4:43 Next up: city generator simulation in HTML, prepare for urban planning
5:02 First city simulation attempt: quite dark, featuring flying cars and rivers
6:10 This city generator is chaos: cars fly, buildings intersect, much like real life
7:07 Multi-file city simulation: a much improved, colorful, and organized metropolis
8:24 City simulation takeaway: better structure, distinct districts, still some oddities
9:25 Diving into the dungeon crawler challenge, let's hope it works
10:13 Single file dungeon crawler: it failed, a sad day for adventurers
10:34 Multi-file dungeon crawler is our last hope, let's see its organized glory
12:03 Success! The procedural dungeon crawler is playable, complete with enemies
13:11 Overall thoughts: Codex is a great coding assistant, reliable, but not intelligent

Timestamps by StampBot 🤖