From d7b613d147e95d7e856d28a202cc198d510b46b0 Mon Sep 17 00:00:00 2001
From: Tom Boucher <trekkie@nomorestars.com>
Date: Fri, 17 Apr 2026 09:30:20 -0400
Subject: [PATCH] fix(hooks): check CLAUDECODE env var in read-guard skip
 (#2344) (#2352)

Closes #2344

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
---
 hooks/gsd-read-guard.js                       |  4 +-
 ...ug-2344-read-guard-claudecode-env.test.cjs | 98 +++++++++++++++++++
 2 files changed, 100 insertions(+), 2 deletions(-)
 create mode 100644 tests/bug-2344-read-guard-claudecode-env.test.cjs

diff --git a/hooks/gsd-read-guard.js b/hooks/gsd-read-guard.js
index 335a372d3..1ec61cd01 100644
--- a/hooks/gsd-read-guard.js
+++ b/hooks/gsd-read-guard.js
@@ -36,8 +36,8 @@ process.stdin.on('end', () => {
       process.exit(0);
     }
 
-    // Claude Code natively enforces read-before-edit — skip the advisory (#1984)
-    if (process.env.CLAUDE_SESSION_ID) {
+    // Claude Code natively enforces read-before-edit — skip the advisory (#1984, #2344)
+    if (process.env.CLAUDE_SESSION_ID || process.env.CLAUDECODE) {
       process.exit(0);
     }
 
diff --git a/tests/bug-2344-read-guard-claudecode-env.test.cjs b/tests/bug-2344-read-guard-claudecode-env.test.cjs
new file mode 100644
index 000000000..c38596933
--- /dev/null
+++ b/tests/bug-2344-read-guard-claudecode-env.test.cjs
@@ -0,0 +1,98 @@
+/**
+ * Regression test for bug #2344
+ *
+ * gsd-read-guard.js checked process.env.CLAUDE_SESSION_ID to detect the
+ * Claude Code runtime and skip its advisory. However, Claude Code CLI exports
+ * CLAUDECODE=1, not CLAUDE_SESSION_ID. The skip never fired, so the
+ * READ-BEFORE-EDIT advisory injected on every Edit/Write call inside Claude
+ * Code — producing noise in long-running sessions.
+ *
+ * Fix: check CLAUDECODE (and CLAUDE_SESSION_ID for back-compat) before
+ * emitting the advisory.
+ */
+
+process.env.GSD_TEST_MODE = '1';
+
+const { test, describe, beforeEach, afterEach } = require('node:test');
+const assert = require('node:assert/strict');
+const fs = require('node:fs');
+const path = require('node:path');
+const { execFileSync } = require('node:child_process');
+
+const { createTempDir, cleanup } = require('./helpers.cjs');
+
+const HOOK_PATH = path.join(__dirname, '..', 'hooks', 'gsd-read-guard.js');
+
+function runHook(payload, envOverrides = {}) {
+  const input = JSON.stringify(payload);
+  const env = {
+    ...process.env,
+    CLAUDE_SESSION_ID: '',
+    CLAUDECODE: '',
+    ...envOverrides,
+  };
+  try {
+    const stdout = execFileSync(process.execPath, [HOOK_PATH], {
+      input,
+      encoding: 'utf-8',
+      timeout: 5000,
+      stdio: ['pipe', 'pipe', 'pipe'],
+      env,
+    });
+    return { exitCode: 0, stdout: stdout.trim(), stderr: '' };
+  } catch (err) {
+    return {
+      exitCode: err.status ?? 1,
+      stdout: (err.stdout || '').toString().trim(),
+      stderr: (err.stderr || '').toString().trim(),
+    };
+  }
+}
+
+describe('bug #2344: read guard skips on CLAUDECODE env var', () => {
+  let tmpDir;
+
+  beforeEach(() => { tmpDir = createTempDir('gsd-read-guard-2344-'); });
+  afterEach(() => { cleanup(tmpDir); });
+
+  test('skips advisory when CLAUDECODE=1 is set (Claude Code CLI env)', () => {
+    const filePath = path.join(tmpDir, 'existing.js');
+    fs.writeFileSync(filePath, 'const x = 1;\n');
+
+    const result = runHook(
+      { tool_name: 'Edit', tool_input: { file_path: filePath, old_string: 'const x = 1;', new_string: 'const x = 2;' } },
+      { CLAUDECODE: '1' }
+    );
+
+    assert.equal(result.exitCode, 0);
+    assert.equal(result.stdout, '', 'advisory must not fire when CLAUDECODE=1');
+  });
+
+  test('skips advisory when CLAUDE_SESSION_ID is set (back-compat)', () => {
+    const filePath = path.join(tmpDir, 'existing.js');
+    fs.writeFileSync(filePath, 'const x = 1;\n');
+
+    const result = runHook(
+      { tool_name: 'Edit', tool_input: { file_path: filePath, old_string: 'const x = 1;', new_string: 'const x = 2;' } },
+      { CLAUDE_SESSION_ID: 'test-session-123' }
+    );
+
+    assert.equal(result.exitCode, 0);
+    assert.equal(result.stdout, '', 'advisory must not fire when CLAUDE_SESSION_ID is set');
+  });
+
+  test('still injects advisory when neither CLAUDECODE nor CLAUDE_SESSION_ID is set', () => {
+    const filePath = path.join(tmpDir, 'existing.js');
+    fs.writeFileSync(filePath, 'const x = 1;\n');
+
+    const result = runHook(
+      { tool_name: 'Edit', tool_input: { file_path: filePath, old_string: 'const x = 1;', new_string: 'const x = 2;' } },
+      { CLAUDECODE: '', CLAUDE_SESSION_ID: '' }
+    );
+
+    assert.equal(result.exitCode, 0);
+    assert.ok(result.stdout.length > 0, 'advisory should fire on non-Claude-Code runtimes');
+    const output = JSON.parse(result.stdout);
+    assert.ok(output.hookSpecificOutput?.additionalContext?.includes('Read'));
+  });
+});