From 69c1b3d88afe5778045cf6503238eb38f27e703d Mon Sep 17 00:00:00 2001
From: Garry Tan <garrytan@gmail.com>
Date: Sun, 16 Aug 2026 08:47:06 -0700
Subject: [PATCH] fix(security): guard brain-sync arithmetic against injected
 .brain-last-pull; sanitize _GBRAIN_HOST
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Re-derived from PR #2588 under the generated-file screening rule (resolver
hunks taken; SKILL.md files regenerated, not accepted). A poisoned
.brain-last-pull could reach bash arithmetic ($(( ))) — a code-execution
vector from a writable state file; the timestamp is now validated numeric
before use. _GBRAIN_HOST from ~/.claude.json is clamped to hostname-safe
characters before echo. Ship goldens refreshed to the regenerated output.

Co-authored-by: sneakygriff <89592870+sneakygriff@users.noreply.github.com>
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 SKILL.md                                                | 3 ++-
 autoplan/SKILL.md                                       | 3 ++-
 benchmark-models/SKILL.md                               | 3 ++-
 benchmark/SKILL.md                                      | 3 ++-
 browse/SKILL.md                                         | 3 ++-
 canary/SKILL.md                                         | 3 ++-
 codex/SKILL.md                                          | 3 ++-
 context-restore/SKILL.md                                | 3 ++-
 context-save/SKILL.md                                   | 3 ++-
 cso/SKILL.md                                            | 3 ++-
 design-consultation/SKILL.md                            | 3 ++-
 design-html/SKILL.md                                    | 3 ++-
 design-review/SKILL.md                                  | 3 ++-
 design-shotgun/SKILL.md                                 | 3 ++-
 devex-review/SKILL.md                                   | 3 ++-
 diagram/SKILL.md                                        | 3 ++-
 document-generate/SKILL.md                              | 3 ++-
 document-release/SKILL.md                               | 3 ++-
 health/SKILL.md                                         | 3 ++-
 investigate/SKILL.md                                    | 3 ++-
 ios-clean/SKILL.md                                      | 3 ++-
 ios-design-review/SKILL.md                              | 3 ++-
 ios-fix/SKILL.md                                        | 3 ++-
 ios-qa/SKILL.md                                         | 3 ++-
 ios-sync/SKILL.md                                       | 3 ++-
 land-and-deploy/SKILL.md                                | 3 ++-
 landing-report/SKILL.md                                 | 3 ++-
 learn/SKILL.md                                          | 3 ++-
 make-pdf/SKILL.md                                       | 3 ++-
 office-hours/SKILL.md                                   | 3 ++-
 open-gstack-browser/SKILL.md                            | 3 ++-
 pair-agent/SKILL.md                                     | 3 ++-
 plan-ceo-review/SKILL.md                                | 3 ++-
 plan-design-review/SKILL.md                             | 3 ++-
 plan-devex-review/SKILL.md                              | 3 ++-
 plan-eng-review/SKILL.md                                | 3 ++-
 plan-tune/SKILL.md                                      | 3 ++-
 qa-only/SKILL.md                                        | 3 ++-
 qa/SKILL.md                                             | 3 ++-
 retro/SKILL.md                                          | 3 ++-
 review/SKILL.md                                         | 3 ++-
 scrape/SKILL.md                                         | 3 ++-
 scripts/resolvers/preamble/generate-brain-sync-block.ts | 3 ++-
 setup-browser-cookies/SKILL.md                          | 3 ++-
 setup-deploy/SKILL.md                                   | 3 ++-
 setup-gbrain/SKILL.md                                   | 3 ++-
 ship/SKILL.md                                           | 3 ++-
 skillify/SKILL.md                                       | 3 ++-
 spec/SKILL.md                                           | 3 ++-
 sync-gbrain/SKILL.md                                    | 3 ++-
 test/fixtures/golden/claude-ship-SKILL.md               | 3 ++-
 51 files changed, 102 insertions(+), 51 deletions(-)

diff --git a/SKILL.md b/SKILL.md
index b7f170567..7e2acdabf 100644
--- a/SKILL.md
+++ b/SKILL.md
@@ -401,6 +401,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -414,7 +415,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/autoplan/SKILL.md b/autoplan/SKILL.md
index f24a1cdcb..66c013051 100644
--- a/autoplan/SKILL.md
+++ b/autoplan/SKILL.md
@@ -536,6 +536,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -549,7 +550,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/benchmark-models/SKILL.md b/benchmark-models/SKILL.md
index 9519c73f6..71608c5a0 100644
--- a/benchmark-models/SKILL.md
+++ b/benchmark-models/SKILL.md
@@ -405,6 +405,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -418,7 +419,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/benchmark/SKILL.md b/benchmark/SKILL.md
index f0528c08f..1c0e27fba 100644
--- a/benchmark/SKILL.md
+++ b/benchmark/SKILL.md
@@ -405,6 +405,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -418,7 +419,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/browse/SKILL.md b/browse/SKILL.md
index d977f363f..5044f5179 100644
--- a/browse/SKILL.md
+++ b/browse/SKILL.md
@@ -403,6 +403,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -416,7 +417,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/canary/SKILL.md b/canary/SKILL.md
index 8b28c47e6..5a2e02158 100644
--- a/canary/SKILL.md
+++ b/canary/SKILL.md
@@ -528,6 +528,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -541,7 +542,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/codex/SKILL.md b/codex/SKILL.md
index ff14f92c8..4470be50d 100644
--- a/codex/SKILL.md
+++ b/codex/SKILL.md
@@ -531,6 +531,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -544,7 +545,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/context-restore/SKILL.md b/context-restore/SKILL.md
index e3dc24782..0481d71fc 100644
--- a/context-restore/SKILL.md
+++ b/context-restore/SKILL.md
@@ -532,6 +532,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -545,7 +546,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/context-save/SKILL.md b/context-save/SKILL.md
index 775b0de48..02d3db51b 100644
--- a/context-save/SKILL.md
+++ b/context-save/SKILL.md
@@ -531,6 +531,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -544,7 +545,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/cso/SKILL.md b/cso/SKILL.md
index 18f7321b0..06c4b37cf 100644
--- a/cso/SKILL.md
+++ b/cso/SKILL.md
@@ -534,6 +534,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -547,7 +548,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/design-consultation/SKILL.md b/design-consultation/SKILL.md
index 241b5c3d8..c7c248aca 100644
--- a/design-consultation/SKILL.md
+++ b/design-consultation/SKILL.md
@@ -554,6 +554,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -567,7 +568,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/design-html/SKILL.md b/design-html/SKILL.md
index 59178c131..742358e34 100644
--- a/design-html/SKILL.md
+++ b/design-html/SKILL.md
@@ -535,6 +535,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -548,7 +549,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/design-review/SKILL.md b/design-review/SKILL.md
index 8e177dfe7..efd98527f 100644
--- a/design-review/SKILL.md
+++ b/design-review/SKILL.md
@@ -532,6 +532,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -545,7 +546,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/design-shotgun/SKILL.md b/design-shotgun/SKILL.md
index 2ba5556ea..f2fc831bf 100644
--- a/design-shotgun/SKILL.md
+++ b/design-shotgun/SKILL.md
@@ -549,6 +549,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -562,7 +563,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/devex-review/SKILL.md b/devex-review/SKILL.md
index 1fe9f52d5..571816f7d 100644
--- a/devex-review/SKILL.md
+++ b/devex-review/SKILL.md
@@ -534,6 +534,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -547,7 +548,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/diagram/SKILL.md b/diagram/SKILL.md
index 04e681ea1..0fc2de22d 100644
--- a/diagram/SKILL.md
+++ b/diagram/SKILL.md
@@ -404,6 +404,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -417,7 +418,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/document-generate/SKILL.md b/document-generate/SKILL.md
index 9eb9e9278..3d7338c99 100644
--- a/document-generate/SKILL.md
+++ b/document-generate/SKILL.md
@@ -534,6 +534,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -547,7 +548,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/document-release/SKILL.md b/document-release/SKILL.md
index de8b965c1..e0a2b106e 100644
--- a/document-release/SKILL.md
+++ b/document-release/SKILL.md
@@ -532,6 +532,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -545,7 +546,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/health/SKILL.md b/health/SKILL.md
index cf1c3177c..352cd3e04 100644
--- a/health/SKILL.md
+++ b/health/SKILL.md
@@ -530,6 +530,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -543,7 +544,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/investigate/SKILL.md b/investigate/SKILL.md
index 2a7d241c9..ebdc934a2 100644
--- a/investigate/SKILL.md
+++ b/investigate/SKILL.md
@@ -569,6 +569,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -582,7 +583,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/ios-clean/SKILL.md b/ios-clean/SKILL.md
index 1d73d8f7b..c0a36bfd6 100644
--- a/ios-clean/SKILL.md
+++ b/ios-clean/SKILL.md
@@ -532,6 +532,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -545,7 +546,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/ios-design-review/SKILL.md b/ios-design-review/SKILL.md
index 8cdc8a024..f61cf9710 100644
--- a/ios-design-review/SKILL.md
+++ b/ios-design-review/SKILL.md
@@ -534,6 +534,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -547,7 +548,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/ios-fix/SKILL.md b/ios-fix/SKILL.md
index 6857d49af..ec12406c2 100644
--- a/ios-fix/SKILL.md
+++ b/ios-fix/SKILL.md
@@ -535,6 +535,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -548,7 +549,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/ios-qa/SKILL.md b/ios-qa/SKILL.md
index 5540914be..6e56ea4ed 100644
--- a/ios-qa/SKILL.md
+++ b/ios-qa/SKILL.md
@@ -538,6 +538,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -551,7 +552,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/ios-sync/SKILL.md b/ios-sync/SKILL.md
index 0b1390c1c..18c709d09 100644
--- a/ios-sync/SKILL.md
+++ b/ios-sync/SKILL.md
@@ -532,6 +532,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -545,7 +546,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/land-and-deploy/SKILL.md b/land-and-deploy/SKILL.md
index 0e3d23509..51bf460f3 100644
--- a/land-and-deploy/SKILL.md
+++ b/land-and-deploy/SKILL.md
@@ -527,6 +527,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -540,7 +541,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/landing-report/SKILL.md b/landing-report/SKILL.md
index 4995332ac..49b15e993 100644
--- a/landing-report/SKILL.md
+++ b/landing-report/SKILL.md
@@ -529,6 +529,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -542,7 +543,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/learn/SKILL.md b/learn/SKILL.md
index 85c094c82..d3b82b52f 100644
--- a/learn/SKILL.md
+++ b/learn/SKILL.md
@@ -530,6 +530,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -543,7 +544,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/make-pdf/SKILL.md b/make-pdf/SKILL.md
index 1e181760c..666bad78c 100644
--- a/make-pdf/SKILL.md
+++ b/make-pdf/SKILL.md
@@ -440,6 +440,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -453,7 +454,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/office-hours/SKILL.md b/office-hours/SKILL.md
index 9c7dc5cad..c4b7254c0 100644
--- a/office-hours/SKILL.md
+++ b/office-hours/SKILL.md
@@ -565,6 +565,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -578,7 +579,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/open-gstack-browser/SKILL.md b/open-gstack-browser/SKILL.md
index 6d05a6723..559eaa3b6 100644
--- a/open-gstack-browser/SKILL.md
+++ b/open-gstack-browser/SKILL.md
@@ -403,6 +403,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -416,7 +417,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/pair-agent/SKILL.md b/pair-agent/SKILL.md
index 63f301c72..af608c243 100644
--- a/pair-agent/SKILL.md
+++ b/pair-agent/SKILL.md
@@ -530,6 +530,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -543,7 +544,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/plan-ceo-review/SKILL.md b/plan-ceo-review/SKILL.md
index 65dd790e1..3d5e9b911 100644
--- a/plan-ceo-review/SKILL.md
+++ b/plan-ceo-review/SKILL.md
@@ -559,6 +559,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -572,7 +573,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/plan-design-review/SKILL.md b/plan-design-review/SKILL.md
index 853609247..525e5df68 100644
--- a/plan-design-review/SKILL.md
+++ b/plan-design-review/SKILL.md
@@ -531,6 +531,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -544,7 +545,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/plan-devex-review/SKILL.md b/plan-devex-review/SKILL.md
index 9dc9d8b05..447cd3a1f 100644
--- a/plan-devex-review/SKILL.md
+++ b/plan-devex-review/SKILL.md
@@ -537,6 +537,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -550,7 +551,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/plan-eng-review/SKILL.md b/plan-eng-review/SKILL.md
index 8672c9464..22afb1c10 100644
--- a/plan-eng-review/SKILL.md
+++ b/plan-eng-review/SKILL.md
@@ -535,6 +535,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -548,7 +549,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/plan-tune/SKILL.md b/plan-tune/SKILL.md
index 7f3656d1a..de473b9a2 100644
--- a/plan-tune/SKILL.md
+++ b/plan-tune/SKILL.md
@@ -540,6 +540,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -553,7 +554,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/qa-only/SKILL.md b/qa-only/SKILL.md
index 1d58adcc7..eafa358de 100644
--- a/qa-only/SKILL.md
+++ b/qa-only/SKILL.md
@@ -530,6 +530,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -543,7 +544,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/qa/SKILL.md b/qa/SKILL.md
index ce3633067..b11981476 100644
--- a/qa/SKILL.md
+++ b/qa/SKILL.md
@@ -536,6 +536,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -549,7 +550,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/retro/SKILL.md b/retro/SKILL.md
index 03f3898dd..5e4d58a1c 100644
--- a/retro/SKILL.md
+++ b/retro/SKILL.md
@@ -547,6 +547,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -560,7 +561,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/review/SKILL.md b/review/SKILL.md
index 2c6fd4b30..263973daf 100644
--- a/review/SKILL.md
+++ b/review/SKILL.md
@@ -532,6 +532,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -545,7 +546,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/scrape/SKILL.md b/scrape/SKILL.md
index 8f73d1cbe..f3ba51a60 100644
--- a/scrape/SKILL.md
+++ b/scrape/SKILL.md
@@ -404,6 +404,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -417,7 +418,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/scripts/resolvers/preamble/generate-brain-sync-block.ts b/scripts/resolvers/preamble/generate-brain-sync-block.ts
index bbd18c2bc..0b0a022a1 100644
--- a/scripts/resolvers/preamble/generate-brain-sync-block.ts
+++ b/scripts/resolvers/preamble/generate-brain-sync-block.ts
@@ -103,6 +103,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -116,7 +117,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server \${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/setup-browser-cookies/SKILL.md b/setup-browser-cookies/SKILL.md
index df6db6027..fb6a056ed 100644
--- a/setup-browser-cookies/SKILL.md
+++ b/setup-browser-cookies/SKILL.md
@@ -399,6 +399,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -412,7 +413,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/setup-deploy/SKILL.md b/setup-deploy/SKILL.md
index d4eb17044..d0b72575f 100644
--- a/setup-deploy/SKILL.md
+++ b/setup-deploy/SKILL.md
@@ -531,6 +531,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -544,7 +545,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/setup-gbrain/SKILL.md b/setup-gbrain/SKILL.md
index 0cc751fbc..73786e36f 100644
--- a/setup-gbrain/SKILL.md
+++ b/setup-gbrain/SKILL.md
@@ -530,6 +530,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -543,7 +544,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/ship/SKILL.md b/ship/SKILL.md
index 1446dd74b..593b76f83 100644
--- a/ship/SKILL.md
+++ b/ship/SKILL.md
@@ -532,6 +532,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -545,7 +546,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/skillify/SKILL.md b/skillify/SKILL.md
index 0bbacd857..e22898eb5 100644
--- a/skillify/SKILL.md
+++ b/skillify/SKILL.md
@@ -529,6 +529,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -542,7 +543,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/spec/SKILL.md b/spec/SKILL.md
index 0a9b1d17f..f51fa9aad 100644
--- a/spec/SKILL.md
+++ b/spec/SKILL.md
@@ -530,6 +530,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -543,7 +544,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/sync-gbrain/SKILL.md b/sync-gbrain/SKILL.md
index 4637351c7..45dc07ce8 100644
--- a/sync-gbrain/SKILL.md
+++ b/sync-gbrain/SKILL.md
@@ -531,6 +531,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -544,7 +545,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0
diff --git a/test/fixtures/golden/claude-ship-SKILL.md b/test/fixtures/golden/claude-ship-SKILL.md
index 1446dd74b..593b76f83 100644
--- a/test/fixtures/golden/claude-ship-SKILL.md
+++ b/test/fixtures/golden/claude-ship-SKILL.md
@@ -532,6 +532,7 @@ if [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_DO_PULL=1
   if [ -f "$_BRAIN_LAST_PULL_FILE" ]; then
     _BRAIN_LAST=$(cat "$_BRAIN_LAST_PULL_FILE" 2>/dev/null || echo 0)
+    case "$_BRAIN_LAST" in ''|*[!0-9]*) _BRAIN_LAST=0 ;; esac
     _BRAIN_AGE=$(( _BRAIN_NOW - _BRAIN_LAST ))
     [ "$_BRAIN_AGE" -lt 86400 ] && _BRAIN_DO_PULL=0
   fi
@@ -545,7 +546,7 @@ fi
 if [ "$_GBRAIN_MCP_MODE" = "remote-http" ]; then
   # Remote-MCP mode: local artifacts sync is a no-op (brain admin's server
   # pulls from GitHub/GitLab). Show the user this is by design, not broken.
-  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|')
+  _GBRAIN_HOST=$(jq -r '.mcpServers.gbrain.url // empty' "$HOME/.claude.json" 2>/dev/null | sed -E 's|^https?://([^/:]+).*|\1|' | head -1 | tr -cd 'A-Za-z0-9._-')
   echo "ARTIFACTS_SYNC: remote-mode (managed by brain server ${_GBRAIN_HOST:-remote})"
 elif [ -d "$_GSTACK_HOME/.git" ] && [ "$_BRAIN_SYNC_MODE" != "off" ]; then
   _BRAIN_QUEUE_DEPTH=0