From 79e7345dccbbdb279afdb56b10284f7166a6a6a2 Mon Sep 17 00:00:00 2001
From: Simon Cropp <simon.cropp@gmail.com>
Date: Thu, 25 Dec 2025 22:45:32 +1100
Subject: [PATCH] Add Cursor CLI detection to AiCliDetector

Introduces detection for the Cursor CLI by checking for the CURSOR_AGENT environment variable. Updates related tests and documentation to include the new IsCursor property.
---
 readme.md                                 | 3 ++-
 src/DiffEngine.Tests/AiCliDetectorTest.cs | 1 +
 src/DiffEngine/AiCliDetector.cs           | 9 ++++++++-
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/readme.md b/readme.md
index d8499ade..ba7f6231 100644
--- a/readme.md
+++ b/readme.md
@@ -178,10 +178,11 @@ There are also individual properties to check for each specific AI CLI
 <a id='snippet-AiCliDetectorProps'></a>
 ```cs
 var isCopilot = AiCliDetector.IsCopilot;
+var isCursor = AiCliDetector.IsCursor;
 var isAider = AiCliDetector.IsAider;
 var isClaudeCode = AiCliDetector.IsClaudeCode;
 ```
-<sup><a href='/src/DiffEngine.Tests/AiCliDetectorTest.cs#L9-L15' title='Snippet source file'>snippet source</a> | <a href='#snippet-AiCliDetectorProps' title='Start of snippet'>anchor</a></sup>
+<sup><a href='/src/DiffEngine.Tests/AiCliDetectorTest.cs#L9-L16' title='Snippet source file'>snippet source</a> | <a href='#snippet-AiCliDetectorProps' title='Start of snippet'>anchor</a></sup>
 <!-- endSnippet -->
 
 
diff --git a/src/DiffEngine.Tests/AiCliDetectorTest.cs b/src/DiffEngine.Tests/AiCliDetectorTest.cs
index acacd970..49acc380 100644
--- a/src/DiffEngine.Tests/AiCliDetectorTest.cs
+++ b/src/DiffEngine.Tests/AiCliDetectorTest.cs
@@ -9,6 +9,7 @@ public void Props()
         #region AiCliDetectorProps
 
         var isCopilot = AiCliDetector.IsCopilot;
+        var isCursor = AiCliDetector.IsCursor;
         var isAider = AiCliDetector.IsAider;
         var isClaudeCode = AiCliDetector.IsClaudeCode;
 
diff --git a/src/DiffEngine/AiCliDetector.cs b/src/DiffEngine/AiCliDetector.cs
index bb822b90..28a780c6 100644
--- a/src/DiffEngine/AiCliDetector.cs
+++ b/src/DiffEngine/AiCliDetector.cs
@@ -18,11 +18,18 @@ static AiCliDetector()
         // https://docs.anthropic.com/en/docs/build-with-claude/claude-cli
         IsClaudeCode = variables.Contains("CLAUDECODE") || variables.Contains("CLAUDE_CODE_ENTRYPOINT");
 
+        // Cursor
+        // https://cursor.com/docs/agent/terminal
+        IsCursor = variables.Contains("CURSOR_AGENT");
+
         Detected = IsCopilot ||
                    IsAider ||
-                   IsClaudeCode;
+                   IsClaudeCode ||
+                   IsCursor;
     }
 
+    public static bool IsCursor { get; set; }
+
     public static bool IsCopilot { get; }
 
     public static bool IsAider { get; }