docs: tagged checkpoints do work on cloud-protected VPGs (#11)

README.md

@@ -64,7 +64,22 @@ Git never had the file. RPO is the journal, not last night's backup.
 
 vSphere ZVM 10.x and ZCA on AWS/Azure, same REST paths. HVM is out (separate swagger). Failover Live is not a tool.
 
-Tagged checkpoints cannot be inserted when the **protected** site is Azure or AWS (Zerto API). Point this server at the vSphere protected ZVM.
+Tagged checkpoints **do** work when the protected site is Azure or AWS. The 9.0 API
+reference says they cannot be inserted; that is wrong on 10.9.10, where both were
+accepted and the task reached `Completed`.
+
+What differs is latency and granularity, both set by the **protected** site:
+
+| protected at | journal gap | tag visible after |
+|---|---|---|
+| vSphere | 5s | ~4s |
+| Azure | 60s | ~34s |
+| AWS | 630s | ~128s |
+
+The tagged checkpoint is also stamped about 30s *after* the insert request, so on a
+cloud-protected VPG a prompt mutation can land *inside* the checkpoint meant to
+precede it. Recover from the newest checkpoint that already existed when the guard
+ran, not from the tag.
 
 ## Not this product
 

skills/zerto-rewind/SKILL.md

@@ -70,7 +70,10 @@ so a stuck session blocks the next recovery. Find it with
 ## Facts that bite
 
 - A tagged checkpoint is crash-consistent, not app-quiesced.
-- Tagged checkpoints are not supported when the **protected** site is Azure or AWS. Talk to the vSphere protected ZVM.
+- Tagged checkpoints work on Azure and AWS protected VPGs, but they appear late:
+  ~34s (Azure) and ~128s (AWS) versus ~4s on vSphere, and the checkpoint is stamped
+  about 30s after you ask for it. On those VPGs the tag can end up *after* your
+  change, so treat the newest checkpoint that already existed as the rewind point.
 - 10.9 FLR Operator RBAC fails; Administrator is the documented workaround.
 - FLR cannot run during clone, test, live failover, or EJC.
 - Linux FLR: files >1.5GB are a bad idea; some characters in names are refused.

src/zerto_rewind_mcp/checkpoints.py

@@ -93,7 +93,10 @@ async def wait_for_tag(
     raise ZertoError(
         f"Tagged checkpoint {tag!r} did not appear on VPG {vpg_identifier} "
         f"within {timeout_s:.0f}s. Do not mutate. "
-        "If the protected site is Azure or AWS, tagged checkpoints are not supported."
+        "On a cloud-protected VPG the tag routinely takes longer than this to appear "
+        "(measured ~34s on Azure, ~128s on AWS), so this timeout may simply be too "
+        "short rather than the insert having failed. Check the Zerto task before "
+        "assuming it did not land."
     )
 
 

src/zerto_rewind_mcp/protection.py

@@ -137,8 +137,7 @@ def find_from_rows(query: str, rows: list[dict[str, Any]]) -> FindResult:
             outcome="none",
             query=query,
             message=(
-                f"VM {vm.vm_name} ({vm.vm_identifier}) has no VPG. "
-                "Unprotected: refuse the change."
+                f"VM {vm.vm_name} ({vm.vm_identifier}) has no VPG. Unprotected: refuse the change."
             ),
             vm=vm,
         )

src/zerto_rewind_mcp/server.py

@@ -133,8 +133,9 @@ async def zerto_create_tagged_checkpoint(
     the Zerto API accepts, so this is the only place that context can live.
 
     Name format: ai:<agent> | <action> | vm=<vm> | change=<change_id> | <utc>
-    Docs: tagged checkpoints are not supported when the protected site is Azure or AWS;
-    run this against the vSphere protected ZVM.
+    Works on Azure and AWS protected VPGs despite what the 9.0 API reference says,
+    but the tag appears late there (~34s Azure, ~128s AWS) and is stamped after the
+    request, so it may sit after a prompt mutation.
     """
     try:
         result = await _find(query)

src/zerto_rewind_mcp/status.py

@@ -127,7 +127,6 @@ def can_tag(status: int | None, substatus: int | None) -> tuple[bool, str | None
         return False, f"VPG status is {status_name(status)}; not MeetingSLA"
     if substatus in SYNCING:
         return False, (
-            f"VPG is {substatus_name(substatus)}; "
-            "checkpoints are not durable until sync ends"
+            f"VPG is {substatus_name(substatus)}; checkpoints are not durable until sync ends"
         )
     return True, None