Saturday's brief is mostly things you can install before lunch. Two of them hand your agent more power, so the third story, a sandbox that limits what that agent can touch, is the one I'd set up first.
No sponsored or affiliate links in this digest — the links below are sources only.
Story I
REA gives your coding agent a reverse-engineering toolkit, and the repo just passed 377K stars
REA is an MIT-licensed MCP server that connects Claude Code, Codex, Cursor, Gemini CLI and other agents to tools for inspecting native binaries, Electron apps, .NET assemblies and websites. You point it at a feature you like, and the agent explains how it works with evidence, then builds a version for your project. Analysis runs locally. JavaScript and Electron targets need no extra engine; native ones use Hopper, Ghidra or IDA. The repo shows 377,958 stars and about 94K forks as of today. Anything that lives on the vendor's server stays out of reach, per the FAQ.
Link: github.com/morluto/rea
Try it now
Run npx rea-agents setup, pick your agent, approve the config changes and restart it. Then ask: "Understand how search works in [app you own], show me the evidence for each conclusion, and write FEATURES.md separating what runs locally from what depends on a remote server. Don't modify the original app." Stick to software you own or are authorized to inspect.
Story II
Claude code-rendered video has its own prompt libraries now: 703 prompts in one repo, 59 film styles in another
The trend is Claude writing a web page that draws every frame, with headless Chrome capturing it and ffmpeg stitching the MP4. No video model is involved. The biggest collection, awesome-opus5-5-videos, holds 703 prompts, each tied to the creator's original post, and has 10,426 stars. lemo-opuscar adds 59 ready film styles to Claude Code, and mg-styles-15 ships 15 styles with the full prompt and source for each. Expect motion graphics and explainers. Realistic people are out, and the same prompt gives a different film every run.
Link: github.com/yihui-dev/awesome-opus5-5-videos
Try it now
In an empty folder with Node, Chrome and ffmpeg installed, open Claude Code and paste the one-liner that started a lot of this: "make a modern slick and punchy video for a modern startup that works on inference". Swap in your own product. If you want more control, grab a prompt from the repo's prompts folder that matches the look you're after and change only the subject.
Story III
Anthropic's sandbox-runtime puts file and network limits on any process, no container required
sandbox-runtime (srt) is the OS-level sandbox behind Claude Code's sandboxed bash tool, released as an Apache 2.0 npm package that works for any CLI, MCP server or agent. It uses Seatbelt on macOS and bubblewrap on Linux. Windows support is alpha. Reads are allowed by default, writes are denied unless allowed, and network traffic is blocked unless the domain is on your allowlist. Anthropic says sandboxing cut permission prompts in internal Claude Code use by 84%. The project is still labeled a beta research preview.
Link: github.com/anthropics/sandbox-runtime
Try it now
Install with npm install -g @anthropic-ai/sandbox-runtime (Node 22.12+; Linux also needs bubblewrap, socat and ripgrep). Allowlist one domain in ~/.srt-settings.json, then compare srt "curl anthropic.com" with srt "curl example.com". To wrap a local MCP server, change its command in .mcp.json from npx to srt and pass the original command as arguments.
Story IV
Kimi K3.1 Pro trails Opus 5.5 by 0.7 points on Terminal-Bench 4.0 and costs $2 in, $10 out
Moonshot AI released Kimi K3.1 Pro, a 2.8T-parameter MoE with 104B active and a 1M-token context, taking text, images and video. Moonshot reports 65.7% on Terminal-Bench 4.0 against 66.4% for Claude Opus 5.5, and a lead on SWE-Marathon. Those are its own numbers. Science-heavy terminal tasks are the weak spot, more than 25 points behind. The API is OpenAI-compatible at $2 input and $10 output per million tokens, down from $3/$15 for K3. Open weights are promised by November 4, so self-hosting isn't possible yet.
Link: platform.kimi.ai
Try it now
Top up $1 on platform.kimi.ai to unlock the API, then point any OpenAI SDK at Kimi's endpoint with model kimi-k3.1-pro. Thinking is always on, temperature is fixed at 1.0, and reasoning effort defaults to max, so set it to low for quick tests. Return the full assistant message on each turn; the docs warn that dropping reasoning history hurts output. Run your hardest repo task through it next to your current model.
— The Vibe Gate news desk. We read the firehose so you can keep building.