diff --git a/agent-node/src/agent_node/core/regex_patterns.py b/agent-node/src/agent_node/core/regex_patterns.py
index 3186aa1..5756ce7 100644
--- a/agent-node/src/agent_node/core/regex_patterns.py
+++ b/agent-node/src/agent_node/core/regex_patterns.py
@@ -19,11 +19,12 @@
 
 # Protocol Extraction (OSC 1337 / Bracketed)
 TASK_PROTOCOL_FENCE = re.compile(r'1337;Task(Start|End);id=([a-zA-Z0-9-]*)')
-EXIT_CODE_PATTERN = re.compile(r'exit=(\d+)')
+# This matches digits optionally followed by brackets (for split-processing resilience)
+EXIT_CODE_PATTERN = re.compile(r'^(\d+)')
 
 # Echo Suppression Patterns (M9/M7)
 ECHO_START_PATTERN = re.compile(r'echo \s*\[\[1337;Task\^Start;id=[a-zA-Z0-9-]*\]\]\s*&\s*')
-ECHO_END_PATTERN = re.compile(r'\s*&\s*echo \s*\[\[1337;Task\^End;id=[a-zA-Z0-9-]*;exit=%errorlevel%\]\]')
+ECHO_END_PATTERN = re.compile(r'\s*&\s*echo \s*\[\[1337;Task\^End;id=[a-zA-Z0-9-]*;exit=%(__ctx_err|errorlevel)%\]\]')
 ECHO_CLEANUP_ANSI = re.compile(r'echo \x1b]1337;TaskEnd;.*')
 ECHO_CLEANUP_BRACKET = re.compile(r'echo \[\[1337;TaskEnd;.*')
 
@@ -35,7 +36,7 @@
 # Windows ConPTY stream noise filters
 # Matches Windows ConHost title-set sequences: "0;...<title>..." lines
 WIN_TITLE_RE  = re.compile(r'^\s*0;.*$', re.MULTILINE)
-# Matches the 'call "...bat"' invocation line echoed by cmd.exe
-BAT_CALL_RE   = re.compile(r'^\s*call\s+".+\.bat".*$', re.MULTILINE | re.IGNORECASE)
-# Matches the 'del /Q ...' cleanup echo (fallback; @call suppresses this in practice)
-DEL_RE        = re.compile(r'^\s*del\s+/Q\s+".+\.bat".*$', re.MULTILINE | re.IGNORECASE)
+# Matches the '@call "...bat"' invocation line echoed by cmd.exe (accounting for optional @)
+BAT_CALL_RE   = re.compile(r'^\s*@?call\s+".+\.bat".*$', re.MULTILINE | re.IGNORECASE)
+# Matches the '@del /Q ...' cleanup echo (accounting for optional @)
+DEL_RE        = re.compile(r'^\s*@?del\s+/Q\s+".+\.bat".*$', re.MULTILINE | re.IGNORECASE)