fix(init): support git worktree hook shims

AGENTS.md

@@ -98,6 +98,7 @@ Gemini-specific event handling:
 - **`pre-push`**: Auto-pushes `refs/notes/agentnote` to remote. Uses `AGENTNOTE_PUSHING` recursion guard.
 
 Existing hooks are backed up and chained. Compatible with husky/lefthook.
+Git worktrees are supported by keeping session buffers in each worktree's own git dir while sharing the repo-local CLI shim from the common git dir. This must work for bare and non-bare repositories, arbitrary worktree directory layouts, and Agent View-style worktree commits after init from the main checkout.
 
 ### Core modules
 

CLAUDE.md

@@ -98,6 +98,7 @@ Gemini-specific event handling:
 - **`pre-push`**: Auto-pushes `refs/notes/agentnote` to remote. Uses `AGENTNOTE_PUSHING` recursion guard.
 
 Existing hooks are backed up and chained. Compatible with husky/lefthook.
+Git worktrees are supported by keeping session buffers in each worktree's own git dir while sharing the repo-local CLI shim from the common git dir. This must work for bare and non-bare repositories, arbitrary worktree directory layouts, and Agent View-style worktree commits after init from the main checkout.
 
 ### Core modules
 

docs/architecture.md

@@ -184,6 +184,14 @@ Append-only JSONL files, accumulated during a session, rotated after each commit
     └── pre_blobs-<id>.jsonl         # archived at next turn boundary
 ```
 
+In git worktrees, this local temp layer intentionally lives under that
+worktree's own git dir (`.git/worktrees/<name>/agentnote` for a non-bare
+repository, or the equivalent worktree git dir for a bare repository). This
+keeps active session pointers, heartbeats, and uncommitted JSONL buffers
+isolated per worktree regardless of where the user chooses to place the
+worktree directory, while git notes remain shared through the repository's
+common git database.
+
 **Layer 2 — Git notes (`refs/notes/agentnote`)**
 
 The permanent record. One JSON note per commit, written at commit time. Pushable, fetchable, shareable with the team.
@@ -391,6 +399,14 @@ Three git hooks handle commit integration and notes sharing:
 | `post-commit` | After commit succeeds | Reads session ID from the finalized trailer on HEAD, calls `agent-note record <session-id>` to write git note. If `prepare-commit-msg` explicitly marked a stale-heartbeat fallback, calls `agent-note record --fallback-head`, which only records when a session post-edit blob matches a committed HEAD blob. If the current process exposes an adapter-supported session environment such as `CODEX_THREAD_ID`, it may also call `agent-note record --fallback-env` when HEAD still has no Agent Note after the trailer/head attempt; fresh mutating transcript work can become commit-level attribution even when exact `files_touched` is unavailable. Direct file-matched env fallback rows may pull in bounded preceding decision-context prompts for display, but only the matched rows affect attribution. Idempotent — skips if note already exists. |
 | `pre-push` | Before push to remote | Pushes `refs/notes/agentnote` to the actual remote (`$1`) and waits for `push-notes` to finish. Recursion-guarded via `AGENTNOTE_PUSHING` env var. |
 
+Git hooks are installed into the hook directory reported by Git, not by assuming
+`.git/hooks`. For worktrees, the hook script may run with a worktree-specific
+`$GIT_DIR`, so `post-commit` and `pre-push` first try that worktree's local
+Agent Note shim and then fall back to the common git dir shim shared by all
+worktrees. This works for both bare and non-bare repositories, including custom
+worktree directory layouts. It lets a main checkout `agent-note init` support
+commits made inside Claude Agent View-style worktrees.
+
 Session freshness is verified via per-session heartbeat file (`sessions/<id>/heartbeat`). Heartbeat is refreshed by normalized hook events during long turns. `Stop` does NOT invalidate the heartbeat — it fires when the AI finishes responding, not when the session ends. Gemini `SessionEnd` is a real session termination and removes the heartbeat. Missing heartbeat in `prepare-commit-msg` skips trailer injection. Stale heartbeat writes a one-shot fallback marker for brand-new commits only; `post-commit` consumes that marker and records only if the active session has post-edit blob evidence that matches the committed HEAD blobs. Agent-hosted terminals may also expose the current session through adapter-specific environment variables. Today, Codex exposes `CODEX_THREAD_ID`, which lets `post-commit` recover a fresh Codex transcript even when `.git/agentnote/session` points at a stale or unrelated session.
 
 Plain git hook trailer injection also requires file evidence. File-change records or pre-edit blobs count as safe evidence because they can be matched back to committed files. Prompts alone are not enough for plain git hooks: a fresh prompt-only active session might belong to another agent or terminal workflow. Agent hook trailer injection can still preserve prompt-only work because the commit command itself was observed inside the agent. Transcript paths are supporting metadata, not recordable data by themselves. Heartbeat, `SessionStart`, and `transcript_path` metadata alone do not receive dangling `Agentnote-Session` trailers.
@@ -402,11 +418,22 @@ Environment fallback is narrower than trailer injection. It does not trust `.git
 `agent-note init` installs git hooks respecting the repository's hook directory:
 
 ```bash
-# Determine hook directory
-HOOK_DIR=$(git config get core.hooksPath || echo ".git/hooks")
+# Determine the effective hook directory. Git resolves this for normal
+# checkouts, bare repositories, custom core.hooksPath, and worktrees.
+HOOK_DIR=$(git rev-parse --git-path hooks)
 ```
 
-If `core.hooksPath` is set (e.g., by husky, lefthook, or custom configuration), hooks are installed there instead of `.git/hooks/`. This ensures compatibility with any hook manager.
+Git owns hook path resolution. Agent Note therefore asks Git for the effective
+hook directory instead of reconstructing it from `.git/` paths or
+`core.hooksPath`. This keeps hook installation correct for hook managers,
+bare repositories, custom worktree layouts, and Claude Agent View-style
+worktrees.
+
+At runtime, hook scripts first try the worktree-local Agent Note shim under the
+Git-reported `$GIT_DIR`. If that shim does not exist, they fall back to the
+common git-dir shim shared by all worktrees. This lets `agent-note init` run
+from either the main checkout or a linked worktree while still supporting
+commits made from any related worktree.
 
 When an existing hook file is found, agent-note chains to it — the original hook runs first, then agent-note's logic runs. This avoids overwriting user or tool-managed hooks.
 

docs/knowledge/investigations.md

@@ -67,6 +67,17 @@ PR #72 で `--fallback-env` を導入し、PR #74 で stale trailer retry と bo
 
 ## Resolved Investigations
 
+### Claude Agent View / git worktree commit で note が落ちる可能性
+
+- 対象: `agent-note init` が生成する `post-commit` / `pre-push` hook、repo-local CLI shim、worktree 上の plain git commit。
+- 背景: Claude Agent View は background Agent の編集前に `.claude/worktrees/...` 配下の git worktree へ移動する。`git worktree` では `git rev-parse --git-dir` が main repository の `.git` ではなく `.git/worktrees/<name>` を返す。一方、hooks は common git dir 側の hooks を使う。
+- 過去対応: `4c08e7f fix: support git worktree by using git rev-parse --git-dir` により、`.git` が file になる worktree でも実 git dir を解決できるようになっていた。これは session buffer を worktree ごとに分けるためには正しい対応だった。
+- 残っていた問題: main checkout で `agent-note init` した場合、repo-local shim は main 側の `.git/agentnote/bin/agent-note` に作られる。しかし worktree commit の hook 実行時の `$GIT_DIR` は `.git/worktrees/<name>` なので、`$GIT_DIR/agentnote/bin/agent-note` だけを見ると shim が見つからない。結果として trailer があっても `post-commit` が `record` を実行できず、git note が作られない可能性があった。
+- Entire から得た判断: Entire は git worktree を session 分離境界として扱う設計を採っている。Agent Note でも session buffer / active pointer / heartbeat は worktree ごとに分離する方が正しい。ただし CLI shim と hooks は common git dir を共有できるため、session data と executable discovery は分けて考える必要がある。
+- 修正: `agentnoteDir()` は従来通り worktree-specific git dir を使い、session buffer を worktree ごとに分ける。一方で `commonAgentnoteDir()` を追加し、`agent-note init` は current worktree git dir と common git dir の両方に deterministic CLI shim を作る。生成 hook は `$GIT_DIR/agentnote/bin/agent-note` を優先し、見つからなければ `git rev-parse --git-common-dir` の shim を使う。`resolveHookDir()` は fallback 時に `git rev-parse --git-path hooks` を使い、Git が実際に使う hook path に揃える。
+- 追加修正: worktree 対応で hook path が絶対パスになるケースが増えたことで、既存 hook chaining の `String.replace()` replacement 文字列に含まれる `$` / `$'` が JavaScript の replacement token として展開されるバグが表面化した。function replacement に変更し、shell-special path でも backup hook path を壊さないようにした。
+- Regression coverage: `packages/cli/src/commands/init.test.ts` で、main checkout で `agent-note init` した後に `.claude/worktrees/agent-view` worktree を作り、Claude hook event で file evidence を作成し、worktree 内の plain `git commit` から git note が作られることを確認する。この test は worktree-local shim が存在しないことも確認し、common shim fallback を必ず通す。追加 matrix では bare repository (`repo.bare/branch/...`) と non-bare repository の両方、repo 内 nested path、repo 外 custom sibling path、space を含む arbitrary worktree path を通し、Git worktree のディレクトリ命名ルールに依存しないことを固定する。さらに `git worktree add` の主要 mode (`--detach`, `--orphan`, `--lock`, `--relative-paths`)、duplicate basename worktree、`git worktree move` 後の path、worktree-specific `core.hooksPath` を通し、Git worktree の private git dir / common git dir / hook path が変わる仕様境界を regression test に含める。
+
 ### PR #76 deletion-only AI Ratio が 0% になる
 
 - 対象 PR: `#76`