--- title: "What to Build With GPT-6 Astra That Wasn't Worth Trying Before" author: "Ecem Karaman" source: "https://aiwithecem.com/guides/build-with-astra" published: 2026-09-18 tools: ["ChatGPT","Codex"] topics: ["Building","AI Agents"] --- # What to Build With GPT-6 Astra That Wasn't Worth Trying Before On your usual tasks, GPT-6 Astra may not feel dramatically different from the models you already use. The bigger change is in what's now realistic to attempt: playable, explorable and 3D things that used to need a developer, a designer or a studio. Here's where Astra is actually different, five builds to try, and a prompt to find your own. **Details checked against [OpenAI's GPT-6 Astra announcement](https://openai.com/index/gpt-6-astra/), the [Astra model guide](https://developers.openai.com/api/docs/guides/latest-model?model=gpt-6-astra) and [model page](https://developers.openai.com/api/docs/models/gpt-6-astra) on September 18, 2026.** > **In this guide** > > 1. [Where Astra is different](#where-astra-is-different) > 2. [Where to run it](#where-to-run-it) > 3. [Five things to build](#five-things-to-build) > 4. [Where it trips](#where-it-trips) > 5. [Find your own build](#find-your-own-build) > 6. [This weekend](#this-weekend) ## Where Astra is different | Strength | What it means for you | | -------- | --------------------- | | **Computer use in real software** | It works inside tools like Blender, Excel, Power BI and CAD, not just in chat | | **Visual judgment** | Websites, games and renderings come out closer to usable on the first pass | | **Long, steerable tasks** | You can add requirements mid-task without it losing the original goal | | **Following templates** | Decks, docs and spreadsheets match your existing format and style | | **Huge context** | A 1M-token window, with strong recall even near the limit | ## Where to run it - **ChatGPT:** rolling out to Plus, Pro, Business and Enterprise. Enterprise admins have to turn it on. - **Sites in ChatGPT:** build, host and share a web app or game from a prompt. Start in ChatGPT Work or the desktop app. Not available on Free or Go. - **Codex:** for anything that touches files, repos or desktop software. - **API:** `gpt-6-astra`, at $10 per million input tokens and $50 per million output tokens. ## Five things to build **1. An explainer people can play.** Turn your core idea into a two-minute game where the rules make the argument. If you advise teams on coordination, let the player add people to a project and watch the handoffs pile up. *Why Astra:* games plus visual judgment, and Sites can host the result. ```text Build a short browser game that teaches this idea: [your idea]. The player should discover it through the rules, not read it. Keep it under 2 minutes, then give a one-line takeaway at the end. Publish it as a Site. ``` **2. A proposal clients can adjust.** Instead of one fixed plan, give clients sliders for scope, timeline and team size, and show what each change does to the others. *Why Astra:* it's built for long, multi-step work and polished web output. ```text Here's my proposal: [paste]. Pull out the assumptions linking scope, time and resources. Build an interactive page where a client can change them and see the trade-offs, with my recommended option marked. ``` **3. A decision simulator.** Arguments like "we need another hire" usually hide different assumptions. A simulator makes each assumption something you can change and inspect. *Why Astra:* strong spreadsheet and analysis work, and you can steer it mid-task as you think of new assumptions. ```text Build a simple simulator for this decision: [decision]. List every assumption as an input I can change, show the outcome, and flag which assumption the result is most sensitive to. ``` **4. A 3D walkthrough or learning object.** A room you're planning, a product prototype, or a concept that makes more sense when you can rotate it. *Why Astra:* computer use in Blender and game engines is one of its standout demos. Run this in Codex, with Blender installed. ```text Use Blender to build a simple 3D model of [floor plan / object / concept] from these references: [attach]. Add a short camera walkthrough and export a video and a .glb file. ``` **5. Your expertise as a tool.** Package the questions you always ask, the patterns you spot and the mistakes you rule out into something people can work through without booking your time. *Why Astra:* it asks focused questions when your answer changes the result, then builds and hosts the Site. ```text Interview me about how I [your expertise]: the questions I ask, the red flags I look for, and what I recommend when. Then build an interactive advisor Site that walks someone through it and ends with a clear next step. ``` ## Where it trips - **It asks more questions.** It may stop to check when you expected it to keep going. If you want it to run, say so up front, and list the decisions it should still check with you. - **Answers get long.** It leans toward detailed, heavily formatted output. Specify the length and format you want. - **Safety checks can pause work.** In ChatGPT and Codex you may be asked to review an action. In the API, the task stops. - **Big prompts cost more.** Prompts over 272K input tokens are billed at a higher rate for the whole request. - **A working first version isn't a good one.** It can build a game quickly. Making it fun, clear or persuasive is still your job. ## Find your own build Look at what people in other jobs make that you never could, like game studios, video editors and product designers. Then ask which of those would help your work. ```text I work as [role] and my audience is [who]. List 8 things people in other fields make (games, simulators, 3D models, interactive tools, videos) that could help my work if I could now build them. For each, give one concrete version I could build in a weekend and what it would replace. ``` ## This weekend - [ ] Run the prompt above and pick **one** idea - [ ] Build a rough first version with Astra in a single session - [ ] Give it one round of specific feedback - [ ] Show it to one real person, and watch what they do with it before you explain anything - [ ] Decide: keep, cut, or turn into a template for the next one **Go deeper:** [GPT-6 Astra announcement](https://openai.com/index/gpt-6-astra/) · [How to Start a Big Project in Claude Code](/guides/big-projects-claude-code) · [Claude Code vs Codex](/guides/claude-code-vs-codex) · [ChatGPT, End to End](/guides/chatgpt-end-to-end)