Poly vs Zed Delta for steering a coding agent together

Zed's Delta and Poly both let several people steer one live coding agent in the same session. Delta, from Zed Industries and in public beta since September 16, 2026, organizes work in agent threads that bundle the conversation and the code; everyone in a thread can send messages, steer the agent, edit files and comment, and drafts from several people go to the agent as one turn, each attributed to its author. Delta has no agent permission system: it does not ask before calling tools. Poly (usepoly.co) is a browser room where every member prompts in one timeline and any member can approve each change before it happens, with a receipt per turn. Delta is for engineering teams, especially Zed users, who want to replace pull requests. Poly is for a small group, including people who don't code, who want a say before the AI acts.

What Delta does

Zed announced Delta on August 12, 2026 as "a multiplayer environment for coding with agents and reviewing what they build," and opened a public beta on September 16. A thread holds the agent conversation and the code checkout. Everyone in it sees each other's drafts as they type, and pending drafts are sent together as one agent turn, each attributed to its author. The thread's owner controls access, and model usage is billed to whoever sends. Threads are created in Delta's desktop app (Mac, Linux, Windows) for a repository with a Git remote; teammates can join on the web or a phone browser, where turns use Delta-hosted models and can't run commands. Models come from ChatGPT Plus or Pro, Copilot and Grok subscriptions, with a Claude subscription listed as coming, or from API keys for Anthropic, OpenAI, Google, OpenRouter and OpenCode. Delta's docs say agents are not sandboxed.

Where Delta is stronger

• Zed. A fast editor with an existing user base, and review built in: Zed has turned off pull requests on Delta's own repository.
• Everyone writes the turn. Several people's drafts go to the agent together, each with its author.
• Your subscriptions. ChatGPT, Copilot and Grok subscriptions, plus API keys from many providers and local models on desktop.
• Price, for now. Free during the public beta.

Where Poly is stronger

• A say before it acts. Delta does not ask before calling tools. In Poly, the room's mode decides what waits for approval, and any member can approve or reject from their own screen.
• A sandbox. Every Poly turn runs in an isolated sandbox with allowlist-only network access. Delta's agents are not sandboxed.
• Start from a browser. A Poly room needs no desktop app and no Git remote, and the AI can run commands from any seat.
• Built for people who don't code. A timeline, plain-language cards and a live preview of the app.
• Models included. Claude, GPT, Grok, Kimi and Muse, with no subscription or key to bring, and a receipt per turn showing the model, time and cost.

Pricing, side by side

Delta: free during the public beta, per Zed's September 16 post; its pricing page lists Zed's plans, Personal $0 with your own keys, Pro $10 a month with $5 of tokens, and Business $30 per seat. Poly: free to start; $20 or $50 a month for each person who runs the AI, models included, and everyone else in the room is free.

Which should you pick?

• An engineering team, especially Zed users, that wants agent threads to replace pull requests: Delta.
• A team that wants everyone to co-write each prompt, on subscriptions it already has: Delta.
• A group that wants approval before the AI acts, and every turn sandboxed: Poly.
• People who don't code, or anyone who wants to start in a browser with nothing to install: Poly.

More options are in Multiplayer AI tools.