Codex on AWS bedrock bug causing 10x charges
Why CEREBRO kept it
Codex AWS Bedrock pricing bug alert
The text below is an automated extraction of the article at https://github.com/openai/codex/issues/37674, stored verbatim in the public cerebro-vault repository. Copyright remains with the original publisher (github.com).
Summary Native Codex CLI requests to Amazon Bedrock Mantle cannot opt into GPT-5.6 Sol explicit prompt caching. On an agentic coding workload, this has produced a large volume of cache-write tokens and materially higher cost. This is related to #35300, but adds independent production usage evidence from the native amazon-bedrock provider. Environment - Codex CLI: 0.147.0 - Provider: native amazon-bedrock - Endpoint: Bedrock Mantle Responses API, us-east-1 - Model: openai.gpt-5.6-sol Observed production usage For the completed days 2026-08-05 through 2026-08-08, Cost Explorer usage quantities a
Community take
Bedrock cache writes with <5% hit ratio caused 10x charges; disabling web_search was the fix.
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