Add agent-bill to Monitoring & Analytics

[yange0793-dot]

What

agent-bill — a zero-dependency Node CLI that turns local Claude Code + Codex session logs into a token & cost bill: breakdowns by model / day / project, a per-session ranking (--sessions), and a self-contained dark-theme HTML report (--html).

Why it belongs here (quality standards)

• Directly related to Codex CLI: parses ~/.codex/sessions/** natively (incremental last_token_usage accumulation, which handles the mid-session resets of total_token_usage) alongside ~/.claude/projects/** — both tools in one report.
• Clear unique value vs. existing entries (ccusage, tokscale, abtop): the two tools define cached tokens in opposite ways — Codex's input_tokens includes cache hits (subset semantics), Claude Code's input_tokens excludes them (separate counters). agent-bill normalizes both into non-cached / cache-read / cache-write at the parser layer, pinned by tests, so cost estimates aren't silently wrong for one of the two tools. It also never prices unrecognized models — tokens are counted, the model is named in the report, no invented costs.
• Zero npm dependencies, zero network requests — reads local JSONL files, prints a report; auditable in one sitting.
• Actively maintained: v0.4.1 released today, CI on every push, MIT.

npx github:yange0793-dot/agent-bill

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