diff --git a/mempalace/hooks_cli.py b/mempalace/hooks_cli.py
index 19a71e2..4672e85 100644
--- a/mempalace/hooks_cli.py
+++ b/mempalace/hooks_cli.py
@@ -379,10 +379,15 @@ def _extract_themes(messages: list[str], max_themes: int = 3) -> list[str]:
 def _save_diary_direct(
     transcript_path: str,
     session_id: str,
+    wing: str = "",
     toast: bool = False,
 ) -> dict:
     """Write a diary checkpoint by calling the tool function directly (no MCP roundtrip).
 
+    If `wing` is set, the entry lands in that wing (typically the project wing
+    derived from the transcript path). Otherwise falls back to `tool_diary_write`'s
+    default of `wing_session-hook`.
+
     Returns {"count": N, "themes": [...]} on success, {"count": 0} on failure.
     """
     messages = _extract_recent_messages(transcript_path)
@@ -407,6 +412,7 @@ def _save_diary_direct(
             agent_name="session-hook",
             entry=entry,
             topic="checkpoint",
+            wing=wing,
         )
         if result.get("success"):
             _log(f"Diary checkpoint saved: {result.get('entry_id', '?')}")
@@ -481,6 +487,24 @@ def _parse_harness_input(data: dict, harness: str) -> dict:
     }
 
 
+def _wing_from_transcript_path(transcript_path: str) -> str:
+    """Derive a project wing name from a Claude Code transcript path.
+
+    Claude Code stores transcripts at:
+        ~/.claude/projects/-home-<user>-Projects-<project>/session.jsonl
+    We extract <project> and return ``wing_<project>`` to match the
+    AAAK_SPEC convention (``wing_user``, ``wing_agent``, ``wing_code``,
+    ``wing_<project>``…). Falls back to ``wing_sessions``.
+    """
+    # Normalize path separators for cross-platform (Windows backslashes)
+    normalized = transcript_path.replace("\\", "/")
+    match = re.search(r"-Projects-([^/]+?)(?:/|$)", normalized)
+    if match:
+        project = match.group(1).lower().replace(" ", "_")
+        return f"wing_{project}"
+    return "wing_sessions"
+
+
 def hook_stop(data: dict, harness: str):
     """Stop hook: block every N messages for auto-save."""
     parsed = _parse_harness_input(data, harness)
@@ -543,11 +567,15 @@ def hook_stop(data: dict, harness: str):
             silent = True
             toast = False
 
+        project_wing = _wing_from_transcript_path(transcript_path)
+
         if silent:
             # Save directly via Python API — systemMessage renders in terminal
             result = {"count": 0}
             if transcript_path:
-                result = _save_diary_direct(transcript_path, session_id, toast=toast)
+                result = _save_diary_direct(
+                    transcript_path, session_id, wing=project_wing, toast=toast
+                )
                 _ingest_transcript(transcript_path)
             _maybe_auto_ingest(transcript_path)
             # Only advance save marker after successful save
@@ -580,7 +608,8 @@ def hook_stop(data: dict, harness: str):
             if transcript_path:
                 _ingest_transcript(transcript_path)
             _maybe_auto_ingest(transcript_path)
-            _output({"decision": "block", "reason": STOP_BLOCK_REASON})
+            reason = STOP_BLOCK_REASON + f" Write diary entry to wing={project_wing}."
+            _output({"decision": "block", "reason": reason})
     else:
         _output({})
 
diff --git a/mempalace/mcp_server.py b/mempalace/mcp_server.py
index 6fe8225..606ecfb 100644
--- a/mempalace/mcp_server.py
+++ b/mempalace/mcp_server.py
@@ -918,10 +918,10 @@ def tool_kg_stats():
 # ==================== AGENT DIARY ====================
 
 
-def tool_diary_write(agent_name: str, entry: str, topic: str = "general"):
+def tool_diary_write(agent_name: str, entry: str, topic: str = "general", wing: str = ""):
     """
-    Write a diary entry for this agent. Each agent gets its own wing
-    with a diary room. Entries are timestamped and accumulate over time.
+    Write a diary entry for this agent. Entries are timestamped and
+    accumulate over time in a diary room.
 
     This is the agent's personal journal — observations, thoughts,
     what it worked on, what it noticed, what it thinks matters.
@@ -932,7 +932,10 @@ def tool_diary_write(agent_name: str, entry: str, topic: str = "general"):
     except ValueError as e:
         return {"success": False, "error": str(e)}
 
-    wing = f"wing_{agent_name.lower().replace(' ', '_')}"
+    if wing:
+        wing = sanitize_name(wing)
+    else:
+        wing = f"wing_{agent_name.lower().replace(' ', '_')}"
     room = "diary"
     col = _get_collection(create=True)
     if not col:
@@ -987,24 +990,38 @@ def tool_diary_write(agent_name: str, entry: str, topic: str = "general"):
         return {"success": False, "error": str(e)}
 
 
-def tool_diary_read(agent_name: str, last_n: int = 10):
+def tool_diary_read(agent_name: str, last_n: int = 10, wing: str = ""):
     """
     Read an agent's recent diary entries. Returns the last N entries
     in chronological order — the agent's personal journal.
+
+    When ``wing`` is provided, reads from that wing instead of the
+    agent's default ``wing_<agent_name>`` wing.  This lets hooks
+    direct diary reads to a project-specific wing derived from
+    the transcript path.
     """
     try:
         agent_name = sanitize_name(agent_name, "agent_name")
+        if wing:
+            wing = sanitize_name(wing)
     except ValueError as e:
         return {"error": str(e)}
     last_n = max(1, min(last_n, 100))
-    wing = f"wing_{agent_name.lower().replace(' ', '_')}"
+    if not wing:
+        wing = f"wing_{agent_name.lower().replace(' ', '_')}"
     col = _get_collection()
     if not col:
         return _no_palace()
 
     try:
         results = col.get(
-            where={"$and": [{"wing": wing}, {"room": "diary"}]},
+            where={
+                "$and": [
+                    {"wing": wing},
+                    {"room": "diary"},
+                    {"agent": agent_name},
+                ]
+            },
             include=["documents", "metadatas"],
             limit=10000,
         )
@@ -1497,6 +1514,10 @@ TOOLS = {
                     "type": "string",
                     "description": "Topic tag (optional, default: general)",
                 },
+                "wing": {
+                    "type": "string",
+                    "description": "Target wing for this diary entry (optional). If omitted, uses wing_{agent_name}. Use this to write diary entries to a project wing instead of an agent-specific wing.",
+                },
             },
             "required": ["agent_name", "entry"],
         },
@@ -1515,6 +1536,10 @@ TOOLS = {
                     "type": "integer",
                     "description": "Number of recent entries to read (default: 10)",
                 },
+                "wing": {
+                    "type": "string",
+                    "description": "Wing to read diary entries from (optional). If omitted, reads from wing_{agent_name}.",
+                },
             },
             "required": ["agent_name"],
         },
diff --git a/tests/test_hooks_cli.py b/tests/test_hooks_cli.py
index d981489..a5af129 100644
--- a/tests/test_hooks_cli.py
+++ b/tests/test_hooks_cli.py
@@ -20,6 +20,7 @@ from mempalace.hooks_cli import (
     _parse_harness_input,
     _sanitize_session_id,
     _validate_transcript_path,
+    _wing_from_transcript_path,
     hook_stop,
     hook_session_start,
     hook_precompact,
@@ -233,7 +234,27 @@ def test_stop_hook_saves_silently_at_interval(tmp_path):
     # Saves silently — systemMessage notification with themes, no block
     assert result["systemMessage"].startswith("\u2726 15 memories woven into the palace")
     assert "hooks" in result["systemMessage"]
-    mock_save.assert_called_once_with(str(transcript), "test", toast=False)
+    # tmp_path has no "-Projects-" segment, so _wing_from_transcript_path falls back to "wing_sessions"
+    mock_save.assert_called_once_with(str(transcript), "test", wing="wing_sessions", toast=False)
+
+
+def test_stop_hook_derives_wing_from_transcript_path(tmp_path):
+    """When transcript path looks like a Claude Code path, wing is derived from it."""
+    project_dir = tmp_path / ".claude" / "projects" / "-home-jp-Projects-myproject"
+    project_dir.mkdir(parents=True)
+    transcript = project_dir / "session.jsonl"
+    _write_transcript(
+        transcript,
+        [{"message": {"role": "user", "content": f"msg {i}"}} for i in range(SAVE_INTERVAL)],
+    )
+    save_result = {"count": 15, "themes": []}
+    with patch("mempalace.hooks_cli._save_diary_direct", return_value=save_result) as mock_save:
+        _capture_hook_output(
+            hook_stop,
+            {"session_id": "test", "stop_hook_active": False, "transcript_path": str(transcript)},
+            state_dir=tmp_path,
+        )
+    mock_save.assert_called_once_with(str(transcript), "test", wing="wing_myproject", toast=False)
 
 
 def test_stop_hook_tracks_save_point(tmp_path):
@@ -281,6 +302,28 @@ def test_precompact_allows(tmp_path):
     assert result == {}
 
 
+# --- _wing_from_transcript_path ---
+
+
+def test_wing_from_transcript_path_extracts_project():
+    path = "/home/jp/.claude/projects/-home-jp-Projects-memorypalace/session.jsonl"
+    assert _wing_from_transcript_path(path) == "wing_memorypalace"
+
+
+def test_wing_from_transcript_path_fallback():
+    assert _wing_from_transcript_path("/some/random/path.jsonl") == "wing_sessions"
+
+
+def test_wing_from_transcript_path_windows_backslashes():
+    path = "C:\\Users\\jp\\.claude\\projects\\-home-jp-Projects-myapp\\session.jsonl"
+    assert _wing_from_transcript_path(path) == "wing_myapp"
+
+
+def test_wing_from_transcript_path_lowercases():
+    path = "/home/jp/.claude/projects/-home-jp-Projects-MyProject/session.jsonl"
+    assert _wing_from_transcript_path(path) == "wing_myproject"
+
+
 # --- _log ---