CLAUDE CODE 2.1.122–2.1.123: BEDROCK TIER SWITCH, BETTER OTEL TYPES, AND AN OAUTH LOOP FIX
Anthropic shipped Claude Code 2.1.122–2.1.123 with a Bedrock tier switch, saner OpenTelemetry types, and a fix for an OAuth 401 retry loop. v2.1.122 adds ANTHR...
Anthropic shipped Claude Code 2.1.122–2.1.123 with a Bedrock tier switch, saner OpenTelemetry types, and a fix for an OAuth 401 retry loop.
v2.1.122 adds ANTHROPIC_BEDROCK_SERVICE_TIER to set the X-Amzn-Bedrock-Service-Tier header (default, flex, priority) for routing on Bedrock, plus a pile of reliability fixes and tweaks. See the notes here.
Observability got cleaner: OTel numeric attributes now ship as numbers (not strings), and there’s a new claude_code.at_mention event. Vertex AI/Bedrock structured-output errors and count_tokens behind proxies were fixed in v2.1.122, and an OAuth 401 loop when disabling experimental betas was resolved in v2.1.123.
You can now steer Bedrock usage by tier to trade cost vs. latency without code changes.
OTel attributes emit as numbers, which simplifies metrics, filters, and alerting.
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terminal
Set ANTHROPIC_BEDROCK_SERVICE_TIER to flex/priority and verify the header, queue times, and cost/latency deltas.
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terminal
Confirm OTel exporters and dashboards handle numeric attributes; re-test structured-output on Vertex AI/Bedrock for no errors.
Legacy codebase integration strategies...
- 01.
Upgrade to 2.1.122+ and audit OTel pipelines/dashboards for attribute type changes from string to number.
- 02.
If CLAUDE_CODE_DISABLE_EXPERIMENTAL_BETAS=1 is used (SSO/locked-down environments), confirm OAuth sign-in no longer loops (2.1.123).
Fresh architecture paradigms...
- 01.
Bake ANTHROPIC_BEDROCK_SERVICE_TIER into config to standardize routing by workload (cost-sensitive vs. latency-critical).
- 02.
Rely on the improved OTel events for cleaner SLOs and at-mention resolution tracing.
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