diff --git a/app/core/brief_agent.py b/app/core/brief_agent.py
index 7fcd00f..954f890 100644
--- a/app/core/brief_agent.py
+++ b/app/core/brief_agent.py
@@ -21,6 +21,7 @@ from app.core.deep_agent import (
     _relational_memory_injection,
     _run_single_agent_stream,
     _trace_id_from_context,
+    build_brief_multi_project_manifest,
 )
 from app.core.langfuse_client import compile_prompt, get_prompt_or_fallback
 
@@ -159,6 +160,8 @@ async def run_home_brief(
     Yields (event_type, data) tuples identical to _run_single_agent_stream.
     Do NOT post-process output through _normalize_tagged_list_lines.
     """
+    from app.agents.folder_agent import FOLDER_TOOLS
+
     trace_id = _trace_id_from_context(context)
     today = date.today().isoformat()
     language = _resolve_language(context)
@@ -171,7 +174,10 @@ async def run_home_brief(
     if today not in system_prompt:
         system_prompt += f"\nToday is {today}."
 
-    tools = _build_read_tools(user_id, trace_id)
+    brief_manifest = await build_brief_multi_project_manifest()
+    system_prompt = system_prompt + ("\n\n" + brief_manifest if brief_manifest else "")
+
+    tools = [*_build_read_tools(user_id, trace_id), *FOLDER_TOOLS]
     async for event in _run_single_agent_stream(
         user_id=user_id,
         system_prompt=system_prompt,
diff --git a/app/core/deep_agent.py b/app/core/deep_agent.py
index e5ac86e..1388c77 100644
--- a/app/core/deep_agent.py
+++ b/app/core/deep_agent.py
@@ -110,6 +110,35 @@ async def _fetch_project_manifest(project_id: str) -> dict | None:
         return None
 
 
+async def build_brief_multi_project_manifest() -> str:
+    """Build a compact multi-project manifest for the daily brief agent.
+
+    Calls execute_on_client('list_projects_with_folder_manifests') and keeps
+    the top 5 most-recently-modified files per project.
+    """
+    try:
+        result = await execute_on_client(
+            action="list_projects_with_folder_manifests",
+            data={},
+        )
+    except Exception:
+        return ""
+    projects = (result or {}).get("projects") or []
+    if not projects:
+        return ""
+    blocks: list[str] = ["<linked_folders>"]
+    for p in projects:
+        files = sorted(p.get("files", []), key=lambda f: f.get("mtimeMs", 0), reverse=True)[:5]
+        if not files:
+            continue
+        blocks.append(f"project: {p.get('projectName','?')} [{p.get('projectId','?')}]")
+        blocks.append(f"  path: {p.get('folderPath','?')}  (scanned {p.get('lastScannedAt','?')})")
+        for f in files:
+            blocks.append(f"  - /{f['relPath']}  [{f.get('kind','text')}]  {f.get('summary','')}")
+    blocks.append("</linked_folders>")
+    return "\n".join(blocks)
+
+
 def _datetime_context_injection(context: dict[str, Any]) -> str:
     """Build a comprehensive DATE CONTEXT block with pre-computed ms-epoch boundaries for common ranges."""
     fp = context.get("format_prefs")
diff --git a/tests/test_manifest_injection.py b/tests/test_manifest_injection.py
index 2405b77..7bb6e48 100644
--- a/tests/test_manifest_injection.py
+++ b/tests/test_manifest_injection.py
@@ -1,7 +1,13 @@
 from __future__ import annotations
 
+from unittest.mock import AsyncMock, patch
+
+import pytest
+
 from app.core.deep_agent import format_folder_manifest, MANIFEST_TOKEN_BUDGET
 
+pytestmark = pytest.mark.asyncio
+
 
 def test_format_folder_manifest_basic():
     manifest = {
@@ -33,3 +39,31 @@ def test_format_folder_manifest_truncates_past_budget():
 def test_format_folder_manifest_null_returns_empty():
     assert format_folder_manifest(None) == ""
     assert format_folder_manifest({"files": []}) == ""
+
+
+async def test_brief_multi_project_manifest_top_5_per_project():
+    fake_response = [
+        {
+            "projectId": "p1", "projectName": "Acme", "folderPath": "/a",
+            "lastScannedAt": "now",
+            "files": [
+                {"relPath": f"f{i}.md", "kind": "text", "summary": "s", "mtimeMs": i}
+                for i in range(10)
+            ],
+        },
+        {
+            "projectId": "p2", "projectName": "Beta", "folderPath": "/b",
+            "lastScannedAt": "now",
+            "files": [{"relPath": "x.md", "kind": "text", "summary": "s", "mtimeMs": 1}],
+        },
+    ]
+    with patch(
+        "app.core.deep_agent.execute_on_client",
+        new=AsyncMock(return_value={"projects": fake_response}),
+    ):
+        from app.core.deep_agent import build_brief_multi_project_manifest
+        out = await build_brief_multi_project_manifest()
+    # Project 1 has 10 files, only top 5 by mtimeMs should appear
+    assert out.count("[p1]") <= 5
+    # Project 2 has 1 file, must appear
+    assert "[p2]" in out or "Beta" in out