Usage, Analyze (beta), and More Durable Attribution

This month we shipped the new git ai usage command and a lot of improvements to attribution and agent integrations.

git ai usage — local AI usage stats without a network connection or an account. Aggregates locally recorded events by period and repo: git ai usage --period 7d --repo myrepo --json.
Refreshed git ai stats and git ai whoami — stats output is easier to parse at a glance, and whoami is reorganized into API, authentication, identity, and telemetry sections. API-key-only users no longer look like a broken logged-out state.
git ai analyze — an early beta of an agent-facing command for researching AI coding activity: ask the analytics backend aggregate questions, pull the sessions behind an answer, and grade transcripts at scale. It's designed to be driven by your coding agent — point it at a question and it discovers the rest from the built-in help. Expect rough edges while it's in beta.
Rewrite operations, rewritten — a ground-up rewrite of how authorship moves through rebase, squash, amend, cherry-pick, restacks, reset, stash, and revert. One object-based core fed by daemon trace2 ingestion replaces the old per-operation machinery, root-causing the attribution loss some teams saw under heavy load. An attribution fuzzer now runs randomized rewrite sequences in CI to keep it that way.
Agent format changes, absorbed — Copilot CLI 1.0.62+ switched to Claude-format tool names, Codex Desktop sends namespaced names like functions.apply_patch, and Cursor added an ApplyPatch tool — each silently left AI edits untracked. All recognized now, along with UTF-16 hook payloads from Cursor (common with CJK content) and shell-command attribution for custom agent-v1 harnesses.
Rebase and cherry-pick edge cases — pull --rebase no longer drops authorship notes when the daemon starts cold, aliases like git up preserve authorship through the rebase, cherry-picks from local remote-tracking refs resolve correctly, and one stale checkpoint entry no longer aborts notes for an entire commit.
A leaner daemon — bounded memory across the board: pull-time attribution no longer diffs entire pulled ranges, stash/pop no longer duplicates checkpoint history, checkpoint file contents are shared instead of copied five times, and every SQLite connection gets a cache cap. Plus a bigger trace socket buffer so bursty operations on large change-sets can't stall git itself.
Custom setups — CODEX_HOME and GEMINI_CLI_HOME are respected for hook installs and transcript sweeps, Droid settings with JSONC comments install cleanly, and metrics upload now authenticates against all API URLs so self-hosted backends actually receive data.
Config and identity — author.name/author.email overrides for machines where the Git committer isn't who's coding, git ai status --diff-only works as documented, and api_base_url, allow_superuser, transcript_streaming_lookback_days, and custom_attributes are all manageable through git ai config.