diff --git a/.custodian-brief.md b/.custodian-brief.md
index 14b2afe..d978404 100644
--- a/.custodian-brief.md
+++ b/.custodian-brief.md
@@ -2,12 +2,20 @@
 # Custodian Brief — markitect-filter
 
 **Domain:** markitect  
-**Last synced:** 2026-05-14 21:32 UTC  
+**Last synced:** 2026-05-15 11:00 UTC  
 **State Hub:** http://127.0.0.1:8000 *(adjust if running on a remote machine)*
 
 ## Active Workstreams
 
-*(none — repo may need first-session setup)*
+### Source Attachment Manifest Compatibility
+Progress: 0/5 done  |  workstream_id: `16e5c830-31e3-4070-9e27-65d28ed06595`
+
+**Open tasks:**
+- · P3.1 - Align attachment metadata with Markitect source contracts  `d119daca`
+- · P3.2 - Add EPUB3 embedded resource metadata  `ebcbf480`
+- · P3.3 - Add PDF attachment and image-signal metadata  `d8b7b820`
+- · P3.4 - Preserve checksums and provenance  `ca539c01`
+- · P3.5 - Provide handoff fixtures for render manifests  `f2213a20`
 
 ---
 ## MCP Orientation (when available)