Google adds Plan Mode to Gemini CLI, enabled by default

Gemini CLI switched on Plan Mode for all users on March 11, turning the command‑line agent into a read‑only research assistant that cannot modify files except its own internal plans [2]. The new mode forces the tool to use only safe, read‑only utilities—such as read_file, grep_search, and glob—while it explores a codebase, maps dependencies, and asks clarification questions before proposing any implementation [2].

Users can activate Plan Mode in three ways: set it as the default approval mode via the /settings command, launch the CLI with the flag --approval-mode=plan, or invoke it on the fly with the /plan command or the Shift+Tab shortcut [1][3]. When entered, Gemini CLI pauses any active processing, presents its findings, and waits for the user to approve, iterate, or cancel the generated plan. The plan is saved as a Markdown file in a dedicated plans directory, where developers can edit it directly in their preferred editor, add comments, and have the agent automatically re‑evaluate the revised steps [1].

The design mirrors traditional software engineering practices: first research, then design, and finally plan before any code changes. By restricting tools to read‑only operations, Google aims to eliminate accidental edits and give developers a safe sandbox for complex tasks such as database migrations or security audits. Custom “skills” can further tailor the planning process, injecting domain‑specific checks—like data safety for migrations or accessibility standards for UI work—into the plan generation [1].

While Plan Mode is secure by default, users can adjust its policies by editing the plan.toml file or adding custom rules in ~/.gemini/policies/. However, any tool approvals granted in other modes do not automatically carry over, preserving the read‑only guarantee unless explicitly allowed [1].

The rollout raises the question of adoption: will developers embrace the extra step of planning within the CLI, or will the friction deter usage in fast‑paced environments? Google’s next move may hinge on how seamlessly Plan Mode integrates with existing workflows and whether the added safety translates into measurable productivity gains.