API request fails with Twilio error lacking documentation page or 'more_info' link. Builder sees generic HTTP 400/5xx or code without explanation (e.g., \"Message body is required\" not found in docs at time). SDK throws RestException with message/code but no resolution path.

Twilio REST API returns structured errors with HTTP status, message, optional code (e.g., 21602), and more_info URL. While most (~500+) codes have dedicated docs, new features, edge cases, deprecations, or rare carrier errors may lack pages or have incomplete info. Community fills gaps via SO/GitHub, but SDKs/responses sometimes surface generic HTTP errors without codes. Docs claim 'full list' but real-world shows occasional gaps.