Claude Code hangs on "thinking" in new sessions — never produces output

Description

When opening a new Claude Code session, Claude frequently gets stuck in the "thinking" state and never produces a response. No output is shown regardless of what prompt I send. This happens intermittently — some new sessions work fine, others hang indefinitely.

Returning to a previously working session (that was still open) works normally.

Steps to reproduce

1. Open a new Claude Code session in an existing project
2. Send any message (even a simple "hello")
3. Claude shows thinking/processing but never responds
4. This happens intermittently

Workarounds tried

• Waiting extended periods — does not resolve
• Sending different prompts — no effect
• Returning to a previously opened session — works fine

Environment

• Claude Code version: 2.1.71
• macOS: 26.2 (Build 25C56)
• Node.js: v22.21.1
• Shell: zsh
• Architecture: Darwin (Apple Silicon)

Configuration context

• Project has 4 PreToolUse hooks (all with timeouts: 5-60s)
• settings.local.json has ~142 permission allow rules
• 2 MCP servers enabled (Notion, Figma)
• ~80+ skills registered
• Using AWS Bedrock provider (custom model IDs configured in env)

Expected behavior

New sessions should start and respond to prompts normally.

Actual behavior

New sessions hang on thinking with no output. No error messages shown.