Claude Code v2.1.214 Fixes Session Cost and Token Telemetry Double-Counting on Multi-Frame Streams

Claude Code Changelog·high signal

Session cost and token telemetry were double-counting on streams that emit multiple cumulative `message_delta` frames, meaning reported spend was inflated for exactly the long, heavily-streamed sessions where cost tracking matters most. If you've been budgeting agent runs off `/cost` or OTel token metrics in recent weeks, your baselines are wrong on the high side. The same release adds `message.uuid`, `client_request_id`, and `tool_source` attributes to OpenTelemetry log events for message-level correlation and tool provenance.