Five things worth your attention if you build with AI, about 3 minutes. Join free and get 13 ready-to-paste Starter Prompts for coding agents, vibe coding and game dev right away.
MODEL
1 OpenAI ships GPT-6.1 Terra at half the price
The new middle model targets computer use, visual reasoning and writing. API prices are $1 per million input tokens and $5 per million output, 50% below GPT-5.6 Terra and GPT-6.1 Sol. At max effort it solves 50.3% of Terminal-Bench 4.0, up from 21.5% for GPT-5.6 Terra.
Why builders care: It's gpt-6.1-terra in the API now. OpenAI still points you to Sol or Astra for the hardest coding work, so try Terra on high-volume agent and form-filling jobs first.
2 Mirendil's first model, Fern, holds 10M tokens of context
The new lab pretrained Fern from scratch for a window of up to 10 million tokens, which it puts at about half a million lines of code. Fern 0.1 is the first and smallest of three models, and access is listed as coming soon.
Why builders care: It's aimed at whole-repo work, long logs and agent traces. Retrieval at that length is one thing, reasoning across it is another, so wait for independent tests before planning around it.
3 Cursor's Agent SDK makes an agent a folder of code
instructions.md is the prompt, each file in tools/ is a typed action, and agent-sdk eval checks which tools ran and what the bot replied. Agents wake on GitHub, Slack, webhooks or cron, and deploy to Cursor or your own servers. Version 0.3.0 is the GA release.
Why builders care: Your review bots and triagers get version control and tests like the rest of your code. Start with npx @cursor/agent-sdk init ./my-bot.
4 Kotaro Uchikoshi says mid-size studios now have to use AI
In a Famitsu interview, the Zero Escape writer said a game his team worked on for about a year and a half was fully canceled after a publisher change of direction. He argued mid-size teams now compete with small AI-assisted indies, and that ideas stay human while AI handles endless polish passes.
Why builders care: His pitch is using AI to sweat the details, not to cut corners. That framing works well with a skeptical team.
5 Repo of the day: tstack, Theo's everyday agent skills
Nine MIT-licensed skills for Claude Code and Codex covering the pull request lifecycle: proving a change, a three-model review "council," filing, babysitting CI, rebasing and merging.
Why builders care: Saying "full send" lets the agent merge on its own. Use full-stop if you want the last click.
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