Show HN: Mysti – Claude, Codex, and Gemini debate your code, then synthesize

Posted by bahaAbunojaim 12/23/2025

Show HN: Mysti – Claude, Codex, and Gemini debate your code, then synthesize(github.com)

Hey HN! I'm Baha, creator of Mysti.

The problem: I pay for Claude Pro, ChatGPT Plus, and Gemini but only one could help at a time. On tricky architecture decisions, I wanted a second opinion.

The solution: Mysti lets you pick any two AI agents (Claude Code, Codex, Gemini) to collaborate. They each analyze your request, debate approaches, then synthesize the best solution.

Your prompt → Agent 1 analyzes → Agent 2 analyzes → Discussion → Synthesized solution

Why this matters: each model has different training and blind spots. Two perspectives catch edge cases one would miss. It's like pair programming with two senior devs who actually discuss before answering.

What you get: * Use your existing subscriptions (no new accounts, just your CLI tools) * 16 personas (Architect, Debugger, Security Expert, etc) * Full permission control from read-only to autonomous * Unified context when switching agents

Tech: TypeScript, VS Code Extension API, shells out to claude-code/codex-cli/gemini-cli

License: BSL 1.1, free for personal and educational use, converts to MIT in 2030 (would love input on this, does it make sense to just go MIT?)

GitHub: https://github.com/DeepMyst/Mysti

Would love feedback on the brainstorm mode. Is multi-agent collaboration actually useful or am I just solving my own niche problem?

216 points | 178 commentspage 4

dunkmaster 12/27/2025|

Any benchmarks? For example vs a single model?

bahaAbunojaim 12/27/2025|

It would be great if the community can run some benchmarks and post it on the repo, planning to do that sometime in Jan

RobotToaster 12/27/2025||

That sounds like it could get expensive?

bahaAbunojaim 12/27/2025|

Not if you optimize the tokens used. This is what DeepMyst actually do, one of the things we offer is token optimization where we can reduce up to 80% of the context so even if you use twice the optimized context you will end up with 60% less tokens.

Note that this functionality is not yet integrated with Mysti but we are planning to add it in the near future and happy to accelerate.

I think token optimization will help with larger projects, longer context and avoiding compact.

tomsmithtld 12/27/2025||

the "full" mode where agents critique each other seems more interesting than quick synthesis. curious whether you've seen cases where the debate produces something neither model would've suggested alone?

bahaAbunojaim 12/28/2025|

I was working on a project where I tried Claude code to optimize processing of taichi Kernel and it kept using structure that didn’t work with taichi lang limitations so it kept going on a loop, did the same with codex and faced the same issue then tried to have both agents discuss it and it worked! It saved me several hours

bahaAbunojaim 12/27/2025||

UPDATE: License is now MIT! Super excited to see your contributions and feedback!

Alifatisk 12/27/2025||

This reminds me a lot of eye2.ai, but outside of coding

bahaAbunojaim 12/27/2025|

I will check it out indeed. What is common between the two?

Alifatisk 12/27/2025||

I guess both consult multiple llms and draw conclusion from them to cover blindspots

bahaAbunojaim 12/27/2025||

I think the main difference is that Mysti consults with agents rather than the underlying LLM and in the future potentially the agents can switch LLMs as well

ekropotin 12/27/2025||

How it’s different from PAL MCP (ex ZEN MCP)?

bahaAbunojaim 12/27/2025|

With an MCP the agent needs to write the context to be passed to the MCP then the MCP would run the underlying CLI with that context. Mysti works differently by sharing context directly with the CLIs.

p1esk 12/27/2025||

Why limit to 2 agents? I typically use all 3.

bahaAbunojaim 12/27/2025|

Planning to make it work without that limit, did that to avoid complexity but contributions are welcome

I think once I add cursor and cline then will also try to make it work with any number of agents

nickphx 12/27/2025||

how would using multiple services that are incapable of performing the work correctly result in better work?

bahaAbunojaim 12/27/2025|

This follows a concept called wisdom of the crowd

lostmsu 1/1/2026||

Huh? I just put something along the lines of: "use Gemini (`gemini <query>`) and Claude (`claude -p <query>`) for design review before trying to implement anything and for code review before reporting task completion" in a user-wide AGENTS.md

matt3210 12/27/2025|

For only 3x the cost

bahaAbunojaim 12/27/2025|

Not if you optimize the context