Compiled the curl flags I use most for API debugging. Highlights:

• -w flag for detailed timing (shows DNS, TLS, and server processing time separately)
• --resolve for testing against specific IPs without changing DNS
• --retry with exponential backoff for flaky endpoints
• .curlrc for default settings

The timing breakdown alone has saved me hours of debugging — you immediately see whether the bottleneck is DNS resolution, TLS handshake, or actual server processing time.