diff --git a/src/main/services/ptyManager.ts b/src/main/services/ptyManager.ts
index 6ec398a54..0fc375371 100644
--- a/src/main/services/ptyManager.ts
+++ b/src/main/services/ptyManager.ts
@@ -52,6 +52,7 @@ const AGENT_ENV_VARS = [
   'AZURE_OPENAI_API_ENDPOINT',
   'AZURE_OPENAI_API_KEY',
   'AZURE_OPENAI_KEY',
+  'CLAUDE_CONFIG_DIR',
   'CODEBUFF_API_KEY',
   'COPILOT_CLI_TOKEN',
   'CURSOR_API_KEY',
diff --git a/src/main/utils/shellEnv.ts b/src/main/utils/shellEnv.ts
index 0d3632254..21e001ebe 100644
--- a/src/main/utils/shellEnv.ts
+++ b/src/main/utils/shellEnv.ts
@@ -287,5 +287,19 @@ export function initializeShellEnvironment(): void {
     console.log('[shellEnv] SSH_AUTH_SOCK not detected');
   }
 
+  // Detect CLAUDE_CONFIG_DIR from login shell when not already in process.env.
+  // Electron GUI apps on macOS don't inherit the user's shell profile, so the
+  // var may be missing even if the user has it in ~/.zshrc / ~/.bash_profile.
+  const existingClaudeConfigDir = process.env.CLAUDE_CONFIG_DIR?.trim();
+  if (!existingClaudeConfigDir) {
+    const claudeConfigDir = getShellEnvVar('CLAUDE_CONFIG_DIR');
+    if (claudeConfigDir) {
+      process.env.CLAUDE_CONFIG_DIR = claudeConfigDir;
+      console.log('[shellEnv] Detected CLAUDE_CONFIG_DIR');
+    }
+  } else {
+    process.env.CLAUDE_CONFIG_DIR = existingClaudeConfigDir;
+  }
+
   initializeLocaleEnvironment();
 }
diff --git a/src/renderer/terminal/TerminalSessionManager.ts b/src/renderer/terminal/TerminalSessionManager.ts
index 4e01f009d..fa44aaa5a 100644
--- a/src/renderer/terminal/TerminalSessionManager.ts
+++ b/src/renderer/terminal/TerminalSessionManager.ts
@@ -487,6 +487,29 @@ export class TerminalSessionManager {
         element.style.height = '100%';
       }
 
+      // Fit the terminal immediately after opening so that connectPty() (which
+      // runs asynchronously, waiting on fetchSnapshot IPC) receives the actual
+      // terminal dimensions rather than the fallback initial size.  Without this,
+      // the PTY is spawned at the wrong size and Claude Code's React Ink TUI
+      // receives a SIGWINCH right after startup, which desynchronises its
+      // statusLine line-count counter and breaks statusLine rendering.
+      try {
+        const width = this.container.clientWidth;
+        const height = this.container.clientHeight;
+        if (
+          width >= MIN_RENDERABLE_TERMINAL_WIDTH_PX &&
+          height >= MIN_RENDERABLE_TERMINAL_HEIGHT_PX
+        ) {
+          this.fitAddon.fit();
+          this.options.initialSize = {
+            cols: Math.max(MIN_TERMINAL_COLS, this.terminal.cols),
+            rows: Math.max(MIN_TERMINAL_ROWS, this.terminal.rows),
+          };
+        }
+      } catch {
+        // If fit fails (e.g. zero-size container), leave initialSize unchanged.
+      }
+
       const selectionDisposable = this.terminal.onSelectionChange(() => {
         if (!this.autoCopyOnSelection || this.disposed) return;
         if (!this.terminal.hasSelection()) return;
diff --git a/src/test/main/shellEnv.test.ts b/src/test/main/shellEnv.test.ts
new file mode 100644
index 000000000..3fd2562a6
--- /dev/null
+++ b/src/test/main/shellEnv.test.ts
@@ -0,0 +1,146 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
+
+const execSyncMock = vi.fn();
+
+vi.mock('child_process', () => ({
+  execSync: (...args: any[]) => execSyncMock(...args),
+}));
+
+// Prevent socket-detection calls in detectSshAuthSock from touching real fs
+vi.mock('fs', () => {
+  const mock = {
+    statSync: vi.fn().mockImplementation(() => {
+      throw new Error('ENOENT');
+    }),
+    readdirSync: vi.fn().mockReturnValue([]),
+  };
+  return { ...mock, default: mock };
+});
+
+describe('getShellEnvVar', () => {
+  beforeEach(() => {
+    vi.resetModules();
+    vi.clearAllMocks();
+  });
+
+  it('returns the trimmed value from the shell', async () => {
+    execSyncMock.mockReturnValue('/custom/claude/config\n');
+    const { getShellEnvVar } = await import('../../main/utils/shellEnv');
+    expect(getShellEnvVar('CLAUDE_CONFIG_DIR')).toBe('/custom/claude/config');
+  });
+
+  it('returns undefined when the shell outputs nothing', async () => {
+    execSyncMock.mockReturnValue('');
+    const { getShellEnvVar } = await import('../../main/utils/shellEnv');
+    expect(getShellEnvVar('CLAUDE_CONFIG_DIR')).toBeUndefined();
+  });
+
+  it('returns undefined without calling execSync for invalid var names', async () => {
+    const { getShellEnvVar } = await import('../../main/utils/shellEnv');
+    expect(getShellEnvVar('invalid-name')).toBeUndefined();
+    expect(execSyncMock).not.toHaveBeenCalled();
+  });
+
+  it('returns undefined when execSync throws', async () => {
+    execSyncMock.mockImplementation(() => {
+      throw new Error('shell unavailable');
+    });
+    const { getShellEnvVar } = await import('../../main/utils/shellEnv');
+    expect(getShellEnvVar('CLAUDE_CONFIG_DIR')).toBeUndefined();
+  });
+});
+
+describe('initializeShellEnvironment — CLAUDE_CONFIG_DIR', () => {
+  let savedClaudeConfigDir: string | undefined;
+  let savedLang: string | undefined;
+
+  beforeEach(() => {
+    vi.resetModules();
+    vi.clearAllMocks();
+
+    savedClaudeConfigDir = process.env.CLAUDE_CONFIG_DIR;
+    savedLang = process.env.LANG;
+
+    delete process.env.CLAUDE_CONFIG_DIR;
+
+    // Set a UTF-8 locale so initializeLocaleEnvironment() exits early and
+    // doesn't issue its own execSync calls, keeping the mock simple.
+    process.env.LANG = 'en_US.UTF-8';
+
+    // Default: execSync returns empty (no SSH_AUTH_SOCK from launchctl, no
+    // CLAUDE_CONFIG_DIR from shell, no locale vars).
+    execSyncMock.mockReturnValue('');
+  });
+
+  afterEach(() => {
+    if (savedClaudeConfigDir === undefined) {
+      delete process.env.CLAUDE_CONFIG_DIR;
+    } else {
+      process.env.CLAUDE_CONFIG_DIR = savedClaudeConfigDir;
+    }
+
+    if (savedLang === undefined) {
+      delete process.env.LANG;
+    } else {
+      process.env.LANG = savedLang;
+    }
+  });
+
+  it('sets CLAUDE_CONFIG_DIR from the login shell when absent from process.env', async () => {
+    execSyncMock.mockImplementation((cmd: string) => {
+      if (typeof cmd === 'string' && cmd.includes('CLAUDE_CONFIG_DIR')) {
+        return '/shell/custom/claude\n';
+      }
+      return '';
+    });
+
+    const { initializeShellEnvironment } = await import('../../main/utils/shellEnv');
+    initializeShellEnvironment();
+
+    expect(process.env.CLAUDE_CONFIG_DIR).toBe('/shell/custom/claude');
+  });
+
+  it('does not override CLAUDE_CONFIG_DIR already present in process.env', async () => {
+    process.env.CLAUDE_CONFIG_DIR = '/existing/path';
+    execSyncMock.mockReturnValue('/shell/custom/claude\n');
+
+    const { initializeShellEnvironment } = await import('../../main/utils/shellEnv');
+    initializeShellEnvironment();
+
+    expect(process.env.CLAUDE_CONFIG_DIR).toBe('/existing/path');
+  });
+
+  it('treats whitespace-only CLAUDE_CONFIG_DIR as unset and falls back to shell', async () => {
+    process.env.CLAUDE_CONFIG_DIR = '   ';
+    execSyncMock.mockImplementation((cmd: string) => {
+      if (typeof cmd === 'string' && cmd.includes('CLAUDE_CONFIG_DIR')) {
+        return '/shell/custom/claude\n';
+      }
+      return '';
+    });
+
+    const { initializeShellEnvironment } = await import('../../main/utils/shellEnv');
+    initializeShellEnvironment();
+
+    expect(process.env.CLAUDE_CONFIG_DIR).toBe('/shell/custom/claude');
+  });
+
+  it('trims a padded CLAUDE_CONFIG_DIR already present in process.env', async () => {
+    process.env.CLAUDE_CONFIG_DIR = '  /existing/path  ';
+    execSyncMock.mockReturnValue('/shell/custom/claude\n');
+
+    const { initializeShellEnvironment } = await import('../../main/utils/shellEnv');
+    initializeShellEnvironment();
+
+    expect(process.env.CLAUDE_CONFIG_DIR).toBe('/existing/path');
+  });
+
+  it('leaves CLAUDE_CONFIG_DIR unset when the shell returns nothing', async () => {
+    execSyncMock.mockReturnValue('');
+
+    const { initializeShellEnvironment } = await import('../../main/utils/shellEnv');
+    initializeShellEnvironment();
+
+    expect(process.env.CLAUDE_CONFIG_DIR).toBeUndefined();
+  });
+});