feat(gemini): Gemini CLI plan review integration

README.md

@@ -4,7 +4,7 @@
 
 # Plannotator
 
-Interactive Plan & Code Review for AI Coding Agents. Mark up and refine your plans or code diffs using a visual UI, share for team collaboration, and seamlessly integrate with **Claude Code**, **OpenCode**, **Pi**, and **Codex**.
+Interactive Plan & Code Review for AI Coding Agents. Mark up and refine your plans or code diffs using a visual UI, share for team collaboration, and seamlessly integrate with **Claude Code**, **Copilot CLI**, **Gemini CLI**, **OpenCode**, **Pi**, and **Codex**.
 
 **Plan Mode Demos:**
 <table>
@@ -54,6 +54,7 @@ Plannotator lets you privately share plans, annotations, and feedback with colle
 
 - [Claude Code](#install-for-claude-code)
 - [Copilot CLI](#install-for-copilot-cli)
+- [Gemini CLI](#install-for-gemini-cli)
 - [OpenCode](#install-for-opencode)
 - [Pi](#install-for-pi)
 - [Codex](#install-for-codex)
@@ -116,6 +117,39 @@ See [apps/copilot/README.md](apps/copilot/README.md) for details.
 
 ---
 
+## Install for Gemini CLI
+
+**Install the `plannotator` command:**
+
+**macOS / Linux / WSL:**
+
+```bash
+curl -fsSL https://plannotator.ai/install.sh | bash
+```
+
+**Windows PowerShell:**
+
+```powershell
+irm https://plannotator.ai/install.ps1 | iex
+```
+
+The installer auto-detects Gemini CLI (checks for `~/.gemini`) and configures the plan review hook and policy. It also installs `/plannotator-review` and `/plannotator-annotate` slash commands.
+
+**Then in Gemini CLI:**
+
+```
+/plan                              # Enter plan mode — plans open in your browser
+/plannotator-review                # Code review for current changes
+/plannotator-review <pr-url>       # Review a GitHub pull request
+/plannotator-annotate <file.md>    # Annotate a markdown file
+```
+
+Requires Gemini CLI 0.36.0 or later.
+
+See [apps/gemini/README.md](apps/gemini/README.md) for details.
+
+---
+
 ## Install for OpenCode
 
 Add to your `opencode.json`:

apps/gemini/README.md

@@ -0,0 +1,89 @@
+# Plannotator for Gemini CLI
+
+Interactive plan review, code review, and markdown annotation for Google Gemini CLI.
+
+## Install
+
+**Install the `plannotator` command:**
+
+**macOS / Linux / WSL:**
+
+```bash
+curl -fsSL https://plannotator.ai/install.sh | bash
+```
+
+**Windows PowerShell:**
+
+```powershell
+irm https://plannotator.ai/install.ps1 | iex
+```
+
+The installer auto-detects Gemini CLI (checks for `~/.gemini`) and configures:
+
+- **Policy file** at `~/.gemini/policies/plannotator.toml` — allows `exit_plan_mode` without the TUI confirmation dialog
+- **Hook** in `~/.gemini/settings.json` — intercepts `exit_plan_mode` and opens the browser review UI
+- **Slash commands** at `~/.gemini/commands/` — `/plannotator-review` and `/plannotator-annotate`
+
+## How It Works
+
+### Plan Mode Integration
+
+When you use `/plan` in Gemini CLI:
+
+1. The agent creates a plan and calls `exit_plan_mode`
+2. The user policy auto-allows `exit_plan_mode` (skipping the TUI dialog)
+3. The `BeforeTool` hook intercepts the call, reads the plan from disk, and opens the Plannotator review UI in your browser
+4. You review the plan, optionally add annotations
+5. **Approve** → the plan is accepted and the agent proceeds
+6. **Deny** → the agent receives your feedback and revises the plan
+
+### Available Commands
+
+| Command | Description |
+|---------|-------------|
+| `/plannotator-review` | Open interactive code review for current changes or a PR URL |
+| `/plannotator-review <pr-url>` | Review a GitHub pull request |
+| `/plannotator-annotate <file>` | Open interactive annotation UI for a markdown file |
+
+## Manual Setup
+
+If the installer didn't auto-configure your settings (e.g. `~/.gemini/settings.json` already existed), add the hook manually:
+
+```json
+{
+  "hooks": {
+    "BeforeTool": [
+      {
+        "matcher": "exit_plan_mode",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "plannotator",
+            "timeout": 345600
+          }
+        ]
+      }
+    ]
+  }
+}
+```
+
+## Environment Variables
+
+| Variable | Description |
+|----------|-------------|
+| `PLANNOTATOR_REMOTE` | Set to `1` for remote mode (devcontainer, SSH). Uses fixed port and skips browser open. |
+| `PLANNOTATOR_PORT` | Fixed port to use. Default: random locally, `19432` for remote sessions. |
+| `PLANNOTATOR_BROWSER` | Custom browser to open. macOS: app name or path. Linux/Windows: executable path. |
+| `PLANNOTATOR_SHARE` | Set to `disabled` to turn off URL sharing. |
+
+## Requirements
+
+- Gemini CLI 0.36.0 or later
+- `plannotator` binary on PATH
+
+## Links
+
+- [Website](https://plannotator.ai)
+- [GitHub](https://github.com/backnotprop/plannotator)
+- [Docs](https://plannotator.ai/docs/getting-started/installation/)

apps/gemini/commands/plannotator-annotate.toml

@@ -0,0 +1,10 @@
+description = "Open interactive annotation UI for a markdown file or folder"
+prompt = """
+## Markdown Annotations
+
+!{plannotator annotate {{args}}}
+
+## Your task
+
+Address the annotation feedback above. The user has reviewed the markdown file and provided specific annotations and comments.
+"""

apps/gemini/commands/plannotator-review.toml

@@ -0,0 +1,10 @@
+description = "Open interactive code review for current changes or a PR URL"
+prompt = """
+## Code Review Feedback
+
+!{plannotator review {{args}}}
+
+## Your task
+
+If the review above contains feedback or annotations, address them. If no changes were requested, acknowledge and continue.
+"""

apps/gemini/hooks/plannotator.toml

@@ -0,0 +1,8 @@
+# Plannotator policy for Gemini CLI
+# Allows exit_plan_mode without TUI confirmation so the browser UI is the sole gate.
+# Installed to: ~/.gemini/policies/plannotator.toml
+
+[[rule]]
+toolName = "exit_plan_mode"
+decision = "allow"
+priority = 100

apps/gemini/hooks/settings-snippet.json

@@ -0,0 +1,16 @@
+{
+  "hooks": {
+    "BeforeTool": [
+      {
+        "matcher": "exit_plan_mode",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "plannotator",
+            "timeout": 345600
+          }
+        ]
+      }
+    ]
+  }
+}

apps/hook/server/index.ts

@@ -749,12 +749,30 @@ if (args[0] === "sessions") {
 
   let planContent = "";
   let permissionMode = "default";
+  let isGemini = false;
+  let planFilename = "";
+  let event: Record<string, any>;
   try {
-    const event = JSON.parse(eventJson);
-    planContent = event.tool_input?.plan || "";
+    event = JSON.parse(eventJson);
+
+    // Detect harness: Gemini sends plan_filename (file on disk), Claude Code sends plan (inline)
+    planFilename = event.tool_input?.plan_filename || event.tool_input?.plan_path || "";
+    isGemini = !!planFilename;
+
+    if (isGemini) {
+      // Reconstruct full plan path from transcript_path and session_id:
+      // transcript_path = <projectTempDir>/chats/session-...json
+      // plan lives at   = <projectTempDir>/<session_id>/plans/<plan_filename>
+      const projectTempDir = path.dirname(path.dirname(event.transcript_path));
+      const planFilePath = path.join(projectTempDir, event.session_id, "plans", planFilename);
+      planContent = await Bun.file(planFilePath).text();
+    } else {
+      planContent = event.tool_input?.plan || "";
+    }
+
     permissionMode = event.permission_mode || "default";
-  } catch {
-    console.error("Failed to parse hook event from stdin");
+  } catch (e: any) {
+    console.error(`Failed to parse hook event from stdin: ${e?.message || e}`);
     process.exit(1);
   }
 
@@ -768,7 +786,7 @@ if (args[0] === "sessions") {
   // Start the plan review server
   const server = await startPlannotatorServer({
     plan: planContent,
-    origin: detectedOrigin,
+    origin: isGemini ? "gemini-cli" : detectedOrigin,
     permissionMode,
     sharingEnabled,
     shareBaseUrl,
@@ -802,41 +820,56 @@ if (args[0] === "sessions") {
   // Cleanup
   server.stop();
 
-  // Output JSON for PermissionRequest hook decision control
-  if (result.approved) {
-    // Build updatedPermissions to preserve the current permission mode
-    const updatedPermissions = [];
-    if (result.permissionMode) {
-      updatedPermissions.push({
-        type: "setMode",
-        mode: result.permissionMode,
-        destination: "session",
-      });
+  // Output decision in the appropriate format for the harness
+  if (isGemini) {
+    if (result.approved) {
+      console.log(result.feedback ? JSON.stringify({ systemMessage: result.feedback }) : "{}");
+    } else {
+      console.log(
+        JSON.stringify({
+          decision: "deny",
+          reason: planDenyFeedback(result.feedback || "", "exit_plan_mode", {
+            planFilePath: planFilename,
+          }),
+        })
+      );
     }
+  } else {
+    // Claude Code: PermissionRequest hook decision
+    if (result.approved) {
+      const updatedPermissions = [];
+      if (result.permissionMode) {
+        updatedPermissions.push({
+          type: "setMode",
+          mode: result.permissionMode,
+          destination: "session",
+        });
+      }
 
-    console.log(
-      JSON.stringify({
-        hookSpecificOutput: {
-          hookEventName: "PermissionRequest",
-          decision: {
-            behavior: "allow",
-            ...(updatedPermissions.length > 0 && { updatedPermissions }),
+      console.log(
+        JSON.stringify({
+          hookSpecificOutput: {
+            hookEventName: "PermissionRequest",
+            decision: {
+              behavior: "allow",
+              ...(updatedPermissions.length > 0 && { updatedPermissions }),
+            },
           },
-        },
-      })
-    );
-  } else {
-    console.log(
-      JSON.stringify({
-        hookSpecificOutput: {
-          hookEventName: "PermissionRequest",
-          decision: {
-            behavior: "deny",
-            message: planDenyFeedback(result.feedback || "", "ExitPlanMode"),
+        })
+      );
+    } else {
+      console.log(
+        JSON.stringify({
+          hookSpecificOutput: {
+            hookEventName: "PermissionRequest",
+            decision: {
+              behavior: "deny",
+              message: planDenyFeedback(result.feedback || "", "ExitPlanMode"),
+            },
           },
-        },
-      })
-    );
+        })
+      );
+    }
   }
 
   process.exit(0);

apps/marketing/src/components/landing/HeroSection.astro

@@ -62,6 +62,15 @@ import AnnoReplace from './AnnoReplace.astro';
           <img src="/assets/icon-copilot.svg" alt="" class="w-4 h-4 icon-copilot" />
           <span>Copilot</span>
         </button>
+        <button
+          class="agent-btn"
+          data-agent="gemini"
+          data-command="curl -fsSL https://plannotator.ai/install.sh | bash"
+          data-video=""
+        >
+          <img src="/assets/icon-gemini.png" alt="" class="w-4 h-4" />
+          <span>Gemini</span>
+        </button>
         <button
           class="agent-btn"
           data-agent="opencode"
@@ -214,6 +223,14 @@ import AnnoReplace from './AnnoReplace.astro';
         ],
         detail: 'Then run in Copilot CLI:'
       },
+      gemini: {
+        steps: [
+          '/plannotator-review',
+          '/plannotator-annotate <file.md>',
+          'Use /plan for plan review with browser approval'
+        ],
+        detail: 'Then use in Gemini CLI:'
+      },
       pi: {
         detail: 'Or try without installing: pi -e npm:@plannotator/pi-extension'
       },

packages/editor/App.tsx

@@ -1307,9 +1307,9 @@ const App: React.FC = () => {
                     }}
                     disabled={isSubmitting}
                     isLoading={isSubmitting}
-                    dimmed={origin === 'claude-code' && allAnnotations.length > 0}
+                    dimmed={(origin === 'claude-code' || origin === 'gemini-cli') && allAnnotations.length > 0}
                   />
-                  {origin === 'claude-code' && allAnnotations.length > 0 && (
+                  {(origin === 'claude-code' || origin === 'gemini-cli') && allAnnotations.length > 0 && (
                     <div className="absolute top-full right-0 mt-2 px-3 py-2 bg-popover border border-border rounded-lg shadow-xl text-xs text-foreground w-56 text-center opacity-0 invisible group-hover/approve:opacity-100 group-hover/approve:visible transition-all pointer-events-none z-50">
                       <div className="absolute bottom-full right-4 border-4 border-transparent border-b-border" />
                       <div className="absolute bottom-full right-4 mt-px border-4 border-transparent border-b-popover" />