diff --git a/functions/agents-vault.fish b/functions/agents-vault.fish
index 6cdd3ea..baebb21 100644
--- a/functions/agents-vault.fish
+++ b/functions/agents-vault.fish
@@ -84,6 +84,12 @@
 #   it defaults to off so a backgrounded push can never hang or prompt
 #   invisibly underneath a starting agent.
 #
+#   The agy knowledge copy is merge-only. Files are copied into the vault
+#   but are never removed from it, so a fact deleted upstream from agy's
+#   knowledge store persists in the vault indefinitely, and a restore or a
+#   fresh clone brings it back. Prune such an entry from the vault by hand
+#   if it must really be gone.
+#
 #   Three further variables exist only so the test suite can run against
 #   throwaway directories instead of the real home, and are not meant for
 #   everyday use. __fish_agent_vault_claude_root overrides Claude's
@@ -288,20 +294,36 @@ function agents-vault --description 'track curated agent memory in a host-scoped
     # it). Never out of thin air -- ~/.claude/memory does not exist by
     # default, and fabricating it would invent state Claude never asked
     # for and permanently claim the path.
-    if test -d "$glive"; or test -L "$glive"; or test (count $gvault_content) -gt 0
+    # -e rather than -d on the live side so a *broken* global path (a stray
+    # regular file where the directory belongs) is noticed and reported on
+    # every run, instead of being silently skipped and mistaken for the
+    # absent-by-default case.
+    if test -e "$glive"; or test -L "$glive"; or test (count $gvault_content) -gt 0
+        # Best-effort, exactly like the agy copy above. Global memory is
+        # optional and frequently absent, and this block runs before the
+        # per-project link, so a fault here must warn and continue rather
+        # than return: aborting would let a stray file or a permission
+        # problem at ~/.claude/memory kill the per-project memory backup
+        # and its commit for every project, on every agent launch. The
+        # secondary feature must not take the primary one down with it.
+        #
+        # Continuing is safe: _agents_repo_ensure_symlink validates and
+        # refuses before it mutates anything, so its failure window is the
+        # same whether the caller returns or carries on. $changed stays
+        # untouched unless the link actually succeeded, and nothing is
+        # recorded to make a later run believe the global memory is linked
+        # when it is not -- the next run re-enters this block and retries.
         if not mkdir -p "$gvault"
-            echo "$c_err""agents-vault: could not create $gvault$c_reset" >&2
-            return 1
-        end
-        set -l gmsg (_agents_repo_ensure_symlink "$glive" "$gvault")
-        set -l grc $status
-        if test $grc -ne 0
-            echo "$c_err""agents-vault: could not link $glive$c_reset" >&2
-            return 1
-        end
-        if test -n "$gmsg"
-            set changed 1
-            test $verbose -eq 1; and echo "$c_ok$gmsg$c_reset"
+            echo "$c_warn""agents-vault: could not create $gvault; skipping global memory$c_reset" >&2
+        else
+            set -l gmsg (_agents_repo_ensure_symlink "$glive" "$gvault")
+            set -l grc $status
+            if test $grc -ne 0
+                echo "$c_warn""agents-vault: could not link $glive; global memory not backed up$c_reset" >&2
+            else if test -n "$gmsg"
+                set changed 1
+                test $verbose -eq 1; and echo "$c_ok$gmsg$c_reset"
+            end
         end
     end
 
diff --git a/tests/test-agents-vault.fish b/tests/test-agents-vault.fish
index 1f5a400..33fbdec 100644
--- a/tests/test-agents-vault.fish
+++ b/tests/test-agents-vault.fish
@@ -620,6 +620,65 @@ set -e __fish_agent_vault_claude_root
 set -g __fish_agent_vault_claude_home $HERMETIC_HOME/claude
 set -g __fish_agent_vault_agy_root $HERMETIC_HOME/agy
 
+#   ────────────── a failed global link must not abort the run ────────────
+# The global block runs before the per-project link and before the commit,
+# and global memory is optional and frequently absent. A fault there must
+# never take the primary per-project backup down with it: otherwise a
+# stray file or a permission problem at ~/.claude/memory would break
+# memory backup for every project, on every agent launch.
+echo ""
+echo "== agents-vault (global link failure is non-fatal) =="
+
+set -l vroot8 (mktemp -d); set -ga TMPDIRS $vroot8
+set -l croot8 (mktemp -d); set -ga TMPDIRS $croot8
+set -l chome8 (mktemp -d); set -ga TMPDIRS $chome8
+set -l agy8 (mktemp -d); set -ga TMPDIRS $agy8
+set -g __fish_agent_vault_dir $vroot8/agent-vault
+set -g __fish_agent_vault_claude_root $croot8
+set -g __fish_agent_vault_claude_home $chome8
+set -g __fish_agent_vault_agy_root $agy8
+
+# A regular FILE where the global memory directory belongs.
+# _agents_repo_ensure_symlink refuses to replace a non-directory, so the
+# global link cannot succeed here.
+echo not-a-directory >$chome8/memory
+
+# ... while this project has perfectly good memory waiting to be backed up.
+set -l fp (new_repo https://git.rootiest.dev/rootiest/globalfail.git)
+set -l fslug git.rootiest.dev-rootiest-globalfail
+set -l fmangled (string replace -a '/' '-' -- $fp | string replace -a '.' '-')
+mkdir -p $croot8/$fmangled/memory
+echo project-memory >$croot8/$fmangled/memory/p.md
+
+set -l ferr (mktemp); set -ga TMPDIRS $ferr
+pushd $fp >/dev/null
+set -l frc (agents-vault --silent 2>$ferr; echo $status)
+popd >/dev/null
+set -l fwarn (cat $ferr)
+
+check "global link failure: exits 0" 0 "$frc"
+check "global link failure: warns on stderr" true (string match -q "*$chome8/memory*" -- "$fwarn"; and echo true; or echo false)
+check "global link failure: live file left alone" not-a-directory (cat $chome8/memory)
+
+# The finding itself: the primary, per-project backup must still happen.
+check "global link failure: per-project link still created" true (test -L $croot8/$fmangled/memory; and echo true; or echo false)
+check "global link failure: per-project memory reached the vault" project-memory (cat $vroot8/agent-vault/projects/$fslug/claude/memory/p.md)
+check "global link failure: vault still committed" true (test (git -C $vroot8/agent-vault rev-list --count HEAD) -ge 1; and echo true; or echo false)
+check "global link failure: per-project memory is committed" true (git -C $vroot8/agent-vault ls-files --error-unmatch projects/$fslug/claude/memory/p.md >/dev/null 2>&1; and echo true; or echo false)
+
+# A failed global link must not be recorded as done: the next run has to
+# re-enter the block and warn again, not treat the vault as correct.
+pushd $fp >/dev/null
+set -l ferr2 (mktemp); set -ga TMPDIRS $ferr2
+agents-vault --silent 2>$ferr2
+popd >/dev/null
+check "global link failure: retried on the next run" true (string match -q "*$chome8/memory*" -- (cat $ferr2); and echo true; or echo false)
+
+set -e __fish_agent_vault_dir
+set -e __fish_agent_vault_claude_root
+set -g __fish_agent_vault_claude_home $HERMETIC_HOME/claude
+set -g __fish_agent_vault_agy_root $HERMETIC_HOME/agy
+
 #   ──────────────────────── hermeticity assertion ────────────────────────
 # The whole suite must never have touched the real global agent state. The
 # failure this guards is specific: a global-memory sync with no test