Plan first, then build

Turning it on

Every thread is in either Build or Plan mode, shown on the mode button in the composer. To switch:

• press ⇧Tab in the composer;
• type /plan, or /build (also /default) to go back;
• use Thread › Plan Mode, or Switch to Plan Mode in the command palette.

A project can start its new threads in plan mode: set Mode in the project’s Project Defaults… (see Projects and threads).

Working with the plan

1. Describe what you want and send it. The agent investigates with read-only actions and may ask you questions, which you answer inline.
2. When it proposes a plan, a Plan ready card appears above the composer with the plan itself. You can collapse it to a preview, open it in the transcript, copy it or hide it.
3. To change the plan, just type: in plan mode a new message refines the plan rather than starting the work.
4. When you’re happy, click Implement. Coincide switches the thread to build mode and asks the agent to implement the plan.

Because the plan stays in the thread, you can also switch agents between planning and building: one agent plans, and another receives the plan in its recap and carries it out.

How each agent plans

Coincide uses each agent’s own plan mode where it has one, so the agent’s safeguards apply. Where it doesn’t, Coincide asks for a plan in the prompt.

Limits to keep in mind

• For Grok Build and Antigravity, plan mode is a request in the prompt. A well-behaved agent follows it, but nothing technically stops an edit. If that matters, also choose Ask for approval so every command and edit needs your OK; see Approvals and questions.
• Even with native plan modes, agents can still read files and run read-only commands, and what they read goes to their provider like any turn.
• Switching back to build mode returns the agent to the thread’s normal mode and access setting with the next message.
• The Implement button sends a short message (“Implement the plan.”) in build mode; you can instead switch with ⇧Tab and write your own instructions.