An append-only audit log caught two accounting bugs in a 216-star usage tracker

Short summary

An append-only audit log ingesting every Claude Code assistant message caught two accounting bugs in splitrail, a Rust usage tracker for agentic CLIs. The first bug: Claude Code rewrites session JSONL files in place during resume/compact, causing messages to vanish from recomputed totals — fixed in splitrail 3.6.0 with a SQLite history store. The second bug: splitrail's file discovery caps at directory depth 2, making 54% of live messages in subagent transcripts structurally invisible. Both were fixed within twelve days.

• •Append-only log keyed by message.id caught two bugs in splitrail's Claude Code usage tracking
• •Bug 1: session JSONL rewrites during resume/compact caused historical usage to vanish — fixed via SQLite history store in 3.6.0
• •Bug 2: subagent transcripts at directory depth ≥4 were invisible to splitrail's depth-2 file discovery — 54% of messages missing
• •Token-exact reconciliation: both implementations agreed on 18,548,947 output tokens across 13.5k messages

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