diff --git a/AI_CHANGELOG_TASK_BACKLOG_REFRESH.md b/AI_CHANGELOG_TASK_BACKLOG_REFRESH.md
new file mode 100644
index 0000000..50c4253
--- /dev/null
+++ b/AI_CHANGELOG_TASK_BACKLOG_REFRESH.md
@@ -0,0 +1,13 @@
+# AI Modification Log: Task Backlog Refresh
+
+Date: 2026-06-29
+
+## Summary
+
+- Updated `CODEX_HANDOFF.md` to reflect that the active working branch is `ai` tracking `origin/ai`.
+- Recorded the current requested follow-up task before editing the X/Y/Z x86_64 config files.
+- Added backlog item #35 to track config intent comments and config-specific optimization todos.
+
+## Verification
+
+- Confirmed the worktree was clean on `ai...origin/ai` before this documentation update.
diff --git a/CODEX_HANDOFF.md b/CODEX_HANDOFF.md
index 2e07bbd..e5dd07e 100644
--- a/CODEX_HANDOFF.md
+++ b/CODEX_HANDOFF.md
@@ -9,9 +9,11 @@ This file is the stable restart point for future Codex sessions in this reposito
 ## Current State
 
 - Repository: `X-OpenWrt-New`
-- Branch: `master`
+- Branch: `ai`
+- Remote tracking branch: `origin/ai`
 - Latest completed task batch: continued the GitHub Actions X/Y/Z optimization backlog through multiple high-priority and low-risk maintainability/script items.
-- Latest task commit at handoff update time: `5f3650c validate workflow dispatch inputs`
+- Latest task commit at handoff update time: `1629605 docs update codex handoff`
+- Current requested task: update the todo handoff, then add comments to `Configs/x86_64-X`, `Configs/x86_64-Y`, and `Configs/x86_64-Z`, plus a dedicated config optimization todo list.
 - Backlog file: `NOTES_GHA_XYZ_OPTIMIZATION.md`
 
 ## Completed Backlog Items
@@ -44,6 +46,10 @@ Each code fix has a corresponding `AI_CHANGELOG_*.md` file.
 
 ## Remaining Work
 
+Immediate continuation:
+
+- #35: Document the X/Y/Z x86_64 config intent. Add header comments to `Configs/x86_64-X`, `Configs/x86_64-Y`, and `Configs/x86_64-Z`, then list config-specific optimization points as todos.
+
 The next unresolved backlog items need broader design or more careful behavior decisions:
 
 - #13: Consolidate X/Y/Z workflows. This is a large refactor; prefer a reusable workflow or matrix workflow with a separate review pass.
diff --git a/NOTES_GHA_XYZ_OPTIMIZATION.md b/NOTES_GHA_XYZ_OPTIMIZATION.md
index b70c5ec..d59a252 100644
--- a/NOTES_GHA_XYZ_OPTIMIZATION.md
+++ b/NOTES_GHA_XYZ_OPTIMIZATION.md
@@ -30,6 +30,15 @@ Related directories:
 - `Scripts`: shared build/env/update helper scripts.
 - `CustomFiles`: patches, dependency files and Kconfig fragments injected by scripts.
 
+## Current Progress
+
+Updated: 2026-06-29
+
+- Active work branch: `ai`, tracking `origin/ai`.
+- Completed backlog items in the current AI task series: #1-#12, #14-#16, #20-#22, #27, #28, and #30.
+- The current continuation task is #35: document the X/Y/Z x86_64 config intent and add a config optimization todo list.
+- Larger unresolved items remain below; prefer one scoped commit per backlog item unless batching is requested.
+
 ## Optimization Backlog
 
 ### High Priority
@@ -236,6 +245,11 @@ Related directories:
     - Problem: commented `KERNEL_PATCHVER` lines do not affect OpenWrt config and can mislead later edits.
     - Suggested fix: remove stale comments or move kernel selection into the correct build mechanism.
 
+35. Document X/Y/Z config intent and optimization todos.
+    - Files: `Configs/x86_64-X`, `Configs/x86_64-Y`, `Configs/x86_64-Z`, `NOTES_X86_CONFIG_OPTIMIZATION.md`
+    - Problem: the three x86_64 profiles do not clearly state their intended role, shared maintenance rules, or follow-up cleanup path.
+    - Suggested fix: add safe comment headers to each config and maintain a dedicated todo list for config-specific optimization work.
+
 ## Suggested First Fix Batch
 
 1. Fix Z upload path typo and Z mosdns build-order issue.