Developer spends 10 hours tracing AWS timeout to a self-inflicted credentials bug

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Developer Themis Lex deployed an AI-powered PDF assessment tool called Themis Lex to AWS Amplify for the Women in AI Accelerator Spring 2026 Build Challenge, only to encounter a 28-second timeout error immediately after launch. The app, which uses Claude via AWS Bedrock to generate role-specific AI guidance for court clerks, appeared to work perfectly in local development. The root cause turned out to be a hardcoded credentials object in the AWS SDK client that passed empty strings instead of omitting the field, effectively blocking the SDK's automatic credential provider chain. Because the failure occurred before any application logic ran, the try/catch block logged nothing, making the bug resemble a platform timeout rather than a code error. After ten and a half hours of debugging and a series of fixes including switching to response streaming and a lighter AI model, the app was successfully shipped.

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