feat(setup): show git status in the setup window and explain the Git-URL failure

MCPForUnity/Editor/Dependencies/DependencyManager.cs

@@ -60,6 +60,9 @@ public static DependencyCheckResult CheckAllDependencies()
                 var uvStatus = detector.DetectUv();
                 result.Dependencies.Add(uvStatus);
 
+                // Check git (optional: Package Manager Git-URL installs only)
+                result.Dependencies.Add(detector.DetectGit());
+
                 // Generate summary and recommendations
                 result.GenerateSummary();
                 GenerateRecommendations(result, detector);

MCPForUnity/Editor/Dependencies/PlatformDetectors/IPlatformDetector.cs

@@ -27,6 +27,11 @@ public interface IPlatformDetector
         /// </summary>
         DependencyStatus DetectUv();
 
+        /// <summary>
+        /// Detect git on this platform. Optional: only the Package Manager's Git-URL install path needs it.
+        /// </summary>
+        DependencyStatus DetectGit();
+
         /// <summary>
         /// Get platform-specific installation recommendations
         /// </summary>

MCPForUnity/Editor/Dependencies/PlatformDetectors/PlatformDetectorBase.cs

@@ -64,6 +64,67 @@ public virtual DependencyStatus DetectUv()
         }
 
 
+        // Git is not needed to run the bridge, only to add or update the package from a Git URL
+        // in the Package Manager, which is the install path most users take (issue #1216). It is
+        // reported as optional so a missing git never blocks setup, but the row tells the user why
+        // "Error when executing git command" appeared and how to clear it.
+        public const string GitInstallUrl = "https://git-scm.com/downloads";
+
+        public virtual DependencyStatus DetectGit()
+        {
+            var status = new DependencyStatus("Git", isRequired: false)
+            {
+                InstallationHint = GitInstallUrl
+            };
+
+            try
+            {
+                if (!TryFindInPath("git", out string gitPath))
+                {
+                    status.ErrorMessage = "git not found";
+                    status.Details = "Only needed to add or update MCP for Unity from a Git URL in the Package Manager.";
+                    return status;
+                }
+
+                if (ExecPath.TryRun(gitPath, "--version", null, out string stdout, out string stderr, 5000)
+                    && TryParseGitVersion(string.IsNullOrWhiteSpace(stdout) ? stderr : stdout, out string version))
+                {
+                    status.IsAvailable = true;
+                    status.Version = version;
+                    status.Path = gitPath;
+                    status.Details = "If the Package Manager still reports 'not in a git directory', git is refusing a folder "
+                        + "owned by another user: run  git config --global --add safe.directory <project folder>";
+                    return status;
+                }
+
+                status.ErrorMessage = "git found but did not report a version";
+                status.Path = gitPath;
+            }
+            catch (Exception ex)
+            {
+                status.ErrorMessage = $"Error detecting git: {ex.Message}";
+            }
+
+            return status;
+        }
+
+        /// <summary>Parses "git version 2.45.1.windows.1" or "git version 2.39.5 (Apple Git-154)" into "2.45.1.windows.1" / "2.39.5".</summary>
+        internal static bool TryParseGitVersion(string output, out string version)
+        {
+            version = null;
+            string line = (output ?? string.Empty).Trim();
+            const string prefix = "git version ";
+            if (!line.StartsWith(prefix, StringComparison.OrdinalIgnoreCase))
+            {
+                return false;
+            }
+
+            string rest = line.Substring(prefix.Length).Trim();
+            int end = rest.IndexOfAny(new[] { ' ', '\r', '\n' });
+            version = end >= 0 ? rest.Substring(0, end) : rest;
+            return version.Length > 0 && char.IsDigit(version[0]);
+        }
+
         protected bool TryParseVersion(string version, out int major, out int minor)
         {
             major = 0;

MCPForUnity/Editor/Windows/MCPSetupWindow.cs

@@ -25,6 +25,9 @@ public class MCPSetupWindow : EditorWindow
         private VisualElement uvIndicator;
         private Label uvVersion;
         private Label uvDetails;
+        private VisualElement gitIndicator;
+        private Label gitVersion;
+        private Label gitDetails;
         private Label statusMessage;
         private VisualElement installationSection;
         private Label installationInstructions;
@@ -88,6 +91,9 @@ public void CreateGUI()
             uvIndicator = rootVisualElement.Q<VisualElement>("uv-indicator");
             uvVersion = rootVisualElement.Q<Label>("uv-version");
             uvDetails = rootVisualElement.Q<Label>("uv-details");
+            gitIndicator = rootVisualElement.Q<VisualElement>("git-indicator");
+            gitVersion = rootVisualElement.Q<Label>("git-version");
+            gitDetails = rootVisualElement.Q<Label>("git-details");
             statusMessage = rootVisualElement.Q<Label>("status-message");
             installationSection = rootVisualElement.Q<VisualElement>("installation-section");
             installationInstructions = rootVisualElement.Q<Label>("installation-instructions");
@@ -328,6 +334,13 @@ private void UpdateUI()
                 UpdateDependencyStatus(uvIndicator, uvVersion, uvDetails, uvDep);
             }
 
+            // Update git status (optional dependency: never blocks readiness)
+            var gitDep = _dependencyResult.Dependencies.Find(d => d.Name == "Git");
+            if (gitDep != null)
+            {
+                UpdateDependencyStatus(gitIndicator, gitVersion, gitDetails, gitDep);
+            }
+
             // Offer the one-click uv installer only when uv is actually missing
             bool uvMissing = uvDep != null && !uvDep.IsAvailable;
             if (installUvButton != null)
@@ -367,8 +380,12 @@ private void UpdateDependencyStatus(VisualElement indicator, Label versionLabel,
                 indicator.RemoveFromClassList("valid");
                 indicator.AddToClassList("invalid");
                 versionLabel.text = "Not Found";
-                detailsLabel.text = dep.ErrorMessage ?? "Not available";
-                detailsLabel.style.color = new StyleColor(Color.red);
+                // A missing optional dependency is information, not a blocker: show what it is
+                // for in the neutral colour instead of the red used for required ones.
+                detailsLabel.text = dep.IsRequired
+                    ? dep.ErrorMessage ?? "Not available"
+                    : dep.Details ?? dep.ErrorMessage ?? "Not available";
+                detailsLabel.style.color = new StyleColor(dep.IsRequired ? Color.red : Color.gray);
             }
         }
     }

MCPForUnity/Editor/Windows/MCPSetupWindow.uxml

@@ -11,7 +11,7 @@
             <ui:VisualElement class="section">
                 <ui:Label text="System Requirements" class="section-title" />
                 <ui:VisualElement class="section-content">
-                    <ui:Label text="MCP for Unity requires Python 3.10+ and UV package manager to function." class="help-text description-text" />
+                    <ui:Label text="MCP for Unity requires Python 3.10+ and UV package manager to function. Git is only needed to install or update the package from a Git URL." class="help-text description-text" />
 
                     <!-- Dependency Status -->
                     <ui:VisualElement name="dependency-list">
@@ -34,6 +34,16 @@
                             </ui:VisualElement>
                             <ui:Label name="uv-details" class="help-text dependency-details" />
                         </ui:VisualElement>
+
+                        <!-- Git Status (optional) -->
+                        <ui:VisualElement class="dependency-item">
+                            <ui:VisualElement class="dependency-row">
+                                <ui:Label text="Git (optional)" class="dependency-name" />
+                                <ui:Label name="git-version" text="..." class="setting-value" />
+                                <ui:VisualElement name="git-indicator" class="status-indicator-small" />
+                            </ui:VisualElement>
+                            <ui:Label name="git-details" class="help-text dependency-details" />
+                        </ui:VisualElement>
                     </ui:VisualElement>
 
                     <!-- Overall Status Message -->

TestProjects/UnityMCPTests/Assets/Tests/EditMode/GitDetectionTests.cs

@@ -0,0 +1,66 @@
+using System.Linq;
+using MCPForUnity.Editor.Dependencies;
+using MCPForUnity.Editor.Dependencies.Models;
+using MCPForUnity.Editor.Dependencies.PlatformDetectors;
+using NUnit.Framework;
+
+namespace MCPForUnityTests.Editor
+{
+    public class GitDetectionTests
+    {
+        [TestCase("git version 2.45.1.windows.1", "2.45.1.windows.1")]
+        [TestCase("git version 2.39.5 (Apple Git-154)", "2.39.5")]
+        [TestCase("  git version 2.43.0\n", "2.43.0")]
+        public void TryParseGitVersion_ExtractsTheVersionToken(string output, string expected)
+        {
+            Assert.IsTrue(PlatformDetectorBase.TryParseGitVersion(output, out string version));
+            Assert.AreEqual(expected, version);
+        }
+
+        [TestCase("")]
+        [TestCase(null)]
+        [TestCase("'git' is not recognized as an internal or external command")]
+        [TestCase("git version ")]
+        [TestCase("git version beta")]
+        public void TryParseGitVersion_RejectsAnythingThatIsNotAGitVersionLine(string output)
+        {
+            Assert.IsFalse(PlatformDetectorBase.TryParseGitVersion(output, out _));
+        }
+
+        [Test]
+        public void CheckAllDependencies_ReportsGitAsOptional()
+        {
+            var result = DependencyManager.CheckAllDependencies();
+            var git = result.Dependencies.FirstOrDefault(d => d.Name == "Git");
+
+            Assert.IsNotNull(git, "The dependency check should always include a Git row");
+            Assert.IsFalse(git.IsRequired, "Git must never block setup; only Git-URL installs need it");
+            Assert.AreEqual(PlatformDetectorBase.GitInstallUrl, git.InstallationHint);
+            if (git.IsAvailable)
+            {
+                Assert.IsFalse(string.IsNullOrEmpty(git.Version));
+                Assert.IsFalse(string.IsNullOrEmpty(git.Path));
+            }
+            else
+            {
+                Assert.IsFalse(string.IsNullOrEmpty(git.ErrorMessage));
+            }
+        }
+
+        [Test]
+        public void MissingGit_DoesNotMakeTheSystemNotReady()
+        {
+            // Mirrors what the setup window computes: Python and uv present, git absent.
+            var result = new DependencyCheckResult();
+            result.Dependencies.Add(new DependencyStatus("Python") { IsAvailable = true, Version = "3.12.0" });
+            result.Dependencies.Add(new DependencyStatus("uv Package Manager") { IsAvailable = true, Version = "0.8.0" });
+            result.Dependencies.Add(new DependencyStatus("Git", isRequired: false) { IsAvailable = false, ErrorMessage = "git not found" });
+
+            result.GenerateSummary();
+
+            Assert.IsTrue(result.IsSystemReady);
+            Assert.IsTrue(result.HasMissingOptional);
+            Assert.IsEmpty(result.GetMissingRequired());
+        }
+    }
+}

website/docs/getting-started/install.md

@@ -18,6 +18,8 @@ Three install paths are supported. Pick one. **Git URL** is the fastest if you j
 
 ## Option 1 — Git URL (fastest)
 
+This path needs `git` on your PATH (the Package Manager runs it). If it reports `Error when executing git command`, see [troubleshooting](../guides/troubleshooting.md#package-manager-error-when-executing-git-command--not-in-a-git-directory).
+
 In Unity, open **Window → Package Manager**, click the **`+`** button, choose **Add package from git URL...**, and paste:
 
 ```text

website/docs/guides/troubleshooting.md

@@ -165,6 +165,23 @@ This is a Unity bug (UUM-132096), not an MCP for Unity one.
 
 ---
 
+## Package Manager: "Error when executing git command" / "not in a git directory"
+
+Adding the package from a Git URL makes the Package Manager shell out to `git`. Two things make that fail:
+
+1. **git is not installed or not on PATH.** Install it from [git-scm.com](https://git-scm.com/downloads) and restart Unity so the Editor picks up the new PATH. The setup window (**Window → MCP for Unity → Local Setup Window**) shows a **Git (optional)** row so you can confirm the Editor sees it.
+2. **git refuses the folder.** Newer git versions decline to run inside a directory owned by a different user account (external drives, shared folders, projects created by another account). The Package Manager surfaces this as `fatal: not in a git directory`. Tell git the folder is yours:
+
+```bash
+git config --global --add safe.directory "/path/to/the/parent/folder"
+```
+
+Trusting the parent folder covers every project inside it. Restart Unity and add the package again.
+
+Git is only needed for this install path; the bridge itself does not use it, so a missing git never blocks setup.
+
+*Reported by [@Cherrymocha](https://github.com/CoplayDev/unity-mcp/issues/1216).*
+
 ## Codex: `resources/read failed: unknown MCP server`
 
 The `mcpforunity://` URI names the *resource*, not the server. Some clients take a separate server key on a resource read.