Product Thumbnail

agmsg

Stop copy-pasting between your AI coding agents

Open Source
Developer Tools
Artificial Intelligence
GitHub
Visit WebsiteSee on Product HuntTwitterGithub

Hunted byKoichi FujikawaKoichi Fujikawa

Stop being the copy-paste relay between your AI coding agents. agmsg lets Claude Code, Codex, Gemini CLI, and Copilot CLI message each other directly through a shared SQLite database — no daemon, no network, no Python. Just bash + sqlite3, installed as an Agent Skill. Unlike built-in subagents (single-vendor, ephemeral) or MCP (an agent calling tools), agmsg is vendor-agnostic and persistent. Run several agents — even multiple Claude Code instances — in one room, working together.

Top comment

Hey Product Hunt 👋 I'm Koichi. I run Claude Code as my daily driver and Codex for the hard stuff. Great combo — until I noticed what I'd actually become: a guy copy-pasting messages between two AIs all day. Copy Claude's output, paste into Codex, copy the reply, paste back. Dozens of times a day. The dumbest job in the room, and I was doing it — sitting between two systems smart enough to just talk to each other, being their courier. So I made them talk directly. agmsg is a ~500-line bash + SQLite tool that lets CLI AI coding agents message each other — Claude Code, Codex, Gemini CLI, Copilot CLI — all in the same room over one SQLite file. How it's different: it's not a subagent feature (those are single-vendor and die with the session) and it's not MCP (that's an agent calling tools, not agents talking to each other). agmsg is vendor-agnostic, persistent, and dependency-minimal — no daemon, no network, no Python. It installs as an Agent Skill, so you never patch the agent itself. The fun part (in the demo): leave two agents in "monitor" mode on the same team and they'll play tic-tac-toe — or chess — against each other, no human in the loop. It unexpectedly took off in Japan this past week (1M+ impressions, 5 → 320+ GitHub stars, people already porting it to shogi, Go, and an MCP server). Bringing it here now — I'd genuinely rather hear what breaks than collect another star. 🙏

Comment highlights

forgive my dumb ass for asking this. still an AI noob. for any conversation that happens in claude for instance (not code related), will this help it migrate to say antigravity?

the sqlite-as-message-bus choice is the part i like — no daemon is the right call. the thing i'd worry about with multiple claude code instances in one room is two of them grabbing the same task before either writes back. how do you handle the claim/lock step?


I'm also thinking about how to pit several neural networks against each other to create the best results only for the topic of YouTube videos.

The "sitting between two systems being their courier" framing is painfully accurate - I do this every day with Claude + a browser-driving agent. Shared SQLite over MCP is the right primitive: zero dependency hell, persistent across sessions, and you can grep history later. Following.

The copy-paste shuffle between Cursor, Claude Code and the rest is a real daily tax, so a shared message bus between agents is a smart framing. Does it preserve context and diffs on handoff, or mainly the prompt text?

The persistent room is the part I'd actually use day to day, the 'agents talking' framing kind of undersells it! Does agmsg arbitrate turns at all (a lock, a token) or is sqlite just guaranteeing nobody drops a message and ordering stays the agents' problem?

been playing the copy-paste courier between claude code and codex for months - feels embarrassing in hindsight. the sqlite approach is just right, no extra process to manage and the whole thread is right there to inspect. curious how turn-taking holds up with 3+ agents but the 2-agent case is exactly what i need

Treating agent-to-agent communication as a first-class primitive rather than bolting it on with shared clipboard or file hacks is genuinely clever. We've run into real pain keeping context synchronized across parallel agent tasks, where state drift creates subtle bugs. How do you handle concurrent write conflicts when two agents message the same SQLite channel simultaneously?

The agent-to-agent message routing is the right abstraction. Instead of shared memory you're treating agents as async message consumers. We've hit context fragmentation when chaining Claude with specialized tools and the copy-paste tax compounds fast. How does agmsg handle partial context handoffs when one agent's output exceeds another's context window limit?

the part that jumps out isn't the agents talking to each other — it's that the room is persistent. it's one sqlite file you can open with sqlite3 and read the whole thread, start to finish. running claude code in a plan → implement → review loop, what always bit me was context dying with each subagent, so i'd hand-roll a state file to carry decisions across passes. a room that outlives the session is exactly that, minus the bookkeeping.

The human courier btw two AIs line made me laugh because that's basically what I've been doing lately. How well does this hold up when more than two agents are involved?

For me the copy-paste isn't even the worst part... it's that the second agent loses the why and confidently rewrites stuff the first one got right. Non-technical builder bouncing between Claude Code and Cursor daily. Does agmsg carry intent across the handoff, or just the code and context?

This is exactly the kind of weird but practical tool that makes sense once you use multiple coding agents. Copying output from Claude Code into Codex and back again gets old fast. A simple SQLite-based “room” for agents to talk to each other feels much cleaner than turning the human into the message bus.

About agmsg on Product Hunt

Stop copy-pasting between your AI coding agents

agmsg launched on Product Hunt on June 9th, 2026 and earned 165 upvotes and 27 comments, placing #5 on the daily leaderboard. Stop being the copy-paste relay between your AI coding agents. agmsg lets Claude Code, Codex, Gemini CLI, and Copilot CLI message each other directly through a shared SQLite database — no daemon, no network, no Python. Just bash + sqlite3, installed as an Agent Skill. Unlike built-in subagents (single-vendor, ephemeral) or MCP (an agent calling tools), agmsg is vendor-agnostic and persistent. Run several agents — even multiple Claude Code instances — in one room, working together.

agmsg was featured in Open Source (68.5k followers), Developer Tools (513.7k followers), Artificial Intelligence (470.5k followers) and GitHub (41.3k followers) on Product Hunt. Together, these topics include over 205k products, making this a competitive space to launch in.

Who hunted agmsg?

agmsg was hunted by Koichi Fujikawa. A “hunter” on Product Hunt is the community member who submits a product to the platform — uploading the images, the link, and tagging the makers behind it. Hunters typically write the first comment explaining why a product is worth attention, and their followers are notified the moment they post. Around 79% of featured launches on Product Hunt are self-hunted by their makers, but a well-known hunter still acts as a signal of quality to the rest of the community. See the full all-time top hunters leaderboard to discover who is shaping the Product Hunt ecosystem.

Want to see how agmsg stacked up against nearby launches in real time? Check out the live launch dashboard for upvote speed charts, proximity comparisons, and more analytics.