Poly vs Coshell for multiplayer AI coding

Coshell and Poly make the same claim, that a team should steer one AI coding agent together in one live session, and deliver it in opposite ways. Coshell is a self-hosted "drive" built on OpenCode: you run it on your own laptop or server for $0, bring your own model keys, and your team joins one shared session with a named prompt queue, plan approvals and a shared preview. Poly (usepoly.co) is hosted: nobody installs or configures anything, nobody holds a key, the AI asks before each change, and every turn carries a receipt. Coshell is the choice for a technical team that wants to own its compute. Poly is the choice for a small group that wants to open a tab and build.

What Coshell does

Coshell, formerly ShellTab, launched as a fork of OpenCode in May 2026. A drive runs on your machine or a one-click cloud deploy and dials out to Coshell's edge, so nothing listens on a public port. Inside, one live session holds the whole team: prompts queue with a name on each, you can follow a teammate's view and cursor, a Plan tab approves a plan with per-line comments, every dev-server port becomes a shared browser tab, and commits are authored to whoever prompted. "Overlap" holds a second agent's edit to the same lines and arbitrates. It works with Claude Code, Codex and, by its count, 70 or more models on your own keys. Self-hosting is free and unmetered; Enterprise adds SSO, audit logs and on-prem support.

Where Coshell is stronger

• Free on your own compute. No seats, no metering, your keys, your machine.
• Model breadth. Dozens of models through OpenCode, including free and self-hosted ones.
• Surfaces. A terminal client, a VS Code extension, Slack, phone, and a grid view of several sessions.
• Overlap. A referee for two agents editing the same lines, which Poly does not need because a room runs one turn at a time.

Where Poly is stronger

• Nothing to run. Coshell's first step is installing and hosting a drive, or a cloud deploy. Poly's first step is a browser tab, and every account starts with free credits and no card.
• Approval per change, from any seat. Coshell approves plans; Poly's approval modes put every file change and command on every member's screen before it happens.
• Receipts. Poly names who ran each turn and what it cost. Coshell attributes commits to the prompter but has no per-turn cost.
• No keys anywhere. Coshell runs on your keys, on a machine your teammates share. Poly's platform keys never enter a sandbox and members never hold one.
• A channel the AI cannot read. Coshell's session chat includes an assistant that answers in it. Poly's group chat and polls are hidden from the agent by design.
• Built for people who do not code. Coshell's personas are engineering managers, remote teams and agencies. Poly's room is designed so the person who cannot code can prompt, approve and undo.

Which should you pick?

• A technical team that wants to self-host on its own compute with its own keys, and is comfortable operating it: Coshell.
• You want many models, including free and local ones: Coshell.
• A small group, including non-engineers, that wants to open a browser and build, with approvals and receipts: Poly.
• A pair that wants the argument about the plan to stay out of the prompt: Poly.