diff --git a/lib/response_analyzer.sh b/lib/response_analyzer.sh
index 7f8cb1f0..875b9a5b 100644
--- a/lib/response_analyzer.sh
+++ b/lib/response_analyzer.sh
@@ -156,9 +156,25 @@ parse_json_response() {
 
     # Bug #1 Fix: If exit_signal is still false, check for RALPH_STATUS block in .result field
     # Claude CLI JSON format embeds the RALPH_STATUS block within the .result text field
+    #
+    # Supported emit formats (both must be recognized; do not regress to single-format match):
+    #   1) Canonical separator-marker format (lib/enable_core.sh:560-568):
+    #        ---RALPH_STATUS---
+    #        EXIT_SIGNAL: true
+    #        ---END_RALPH_STATUS---
+    #   2) YAML colon-block format emitted by some agent prompts:
+    #        RALPH_STATUS:
+    #          EXIT_SIGNAL: true
+    #          reason: "..."
+    # The regex anchors at start-of-line (with optional leading whitespace) so prose
+    # mentions of "RALPH_STATUS:" inline (e.g. in commit messages, doc strings, or
+    # tool-result echoes) DO NOT trigger the gate; only block-header lines do.
+    # The downstream EXIT_SIGNAL extraction (grep "EXIT_SIGNAL:" | cut | xargs) handles
+    # both layouts uniformly because both emit one EXIT_SIGNAL: <bool> line.
+    # See also the parallel check at the structured-output text-parsing fallback below.
     if [[ "$exit_signal" == "false" && "$has_result_field" == "true" ]]; then
         local result_text=$(jq -r '.result // ""' "$output_file" 2>/dev/null)
-        if [[ -n "$result_text" ]] && echo "$result_text" | grep -q -- "---RALPH_STATUS---"; then
+        if [[ -n "$result_text" ]] && echo "$result_text" | grep -qE -- "^[[:space:]]*(---RALPH_STATUS---|RALPH_STATUS:)"; then
             # Extract EXIT_SIGNAL value from RALPH_STATUS block within result text
             local embedded_exit_sig
             embedded_exit_sig=$(echo "$result_text" | grep "EXIT_SIGNAL:" | cut -d: -f2 | xargs)
@@ -486,7 +502,15 @@ analyze_response() {
     local explicit_exit_signal_found=false
 
     # 1. Check for explicit structured output (if Claude follows schema)
-    if grep -q -- "---RALPH_STATUS---" "$output_file"; then
+    # Match both the canonical "---RALPH_STATUS---" separator-marker format AND
+    # the YAML colon-block format ("RALPH_STATUS:" with indented keys) some agent
+    # prompts emit. The regex anchors at start-of-line (with optional leading
+    # whitespace) so prose mentions of these tokens inline DO NOT trigger the
+    # gate; only block-header lines do. The downstream EXIT_SIGNAL/STATUS
+    # extraction handles both layouts uniformly because each emits one
+    # "EXIT_SIGNAL: <bool>" line.
+    # See also the parallel check in the JSON-mode .result text path above.
+    if grep -qE -- "^[[:space:]]*(---RALPH_STATUS---|RALPH_STATUS:)" "$output_file"; then
         # Parse structured output
         local status=$(grep "STATUS:" "$output_file" | cut -d: -f2 | xargs)
         local exit_sig=$(grep "EXIT_SIGNAL:" "$output_file" | cut -d: -f2 | xargs)
diff --git a/tests/unit/test_json_parsing.bats b/tests/unit/test_json_parsing.bats
index f48f9feb..bdf2cd72 100644
--- a/tests/unit/test_json_parsing.bats
+++ b/tests/unit/test_json_parsing.bats
@@ -1155,3 +1155,145 @@ EOF
     exit_signal=$(jq -r '.analysis.exit_signal' "$RALPH_DIR/.response_analysis")
     assert_equal "$exit_signal" "false"
 }
+
+# =============================================================================
+# YAML COLON-BLOCK RALPH_STATUS FORMAT TESTS
+# =============================================================================
+# Some agent prompts emit the structured-status block as YAML (colon heading +
+# indented keys) instead of the canonical "---RALPH_STATUS---" separator
+# markers. The detection regex extends to match either form so EXIT_SIGNAL is
+# read out of both layouts; the downstream `grep "EXIT_SIGNAL:" | cut | xargs`
+# extraction is layout-agnostic.
+
+@test "text mode: YAML colon-block RALPH_STATUS with EXIT_SIGNAL=true triggers exit" {
+    local output_file="$LOG_DIR/test_output.log"
+
+    cat > "$output_file" << 'EOF'
+Investigation complete.
+
+RALPH_STATUS:
+  EXIT_SIGNAL: true
+  reason: "All tasks complete"
+
+End of response.
+EOF
+
+    analyze_response "$output_file" 1
+
+    local exit_signal=$(jq -r '.analysis.exit_signal' "$RALPH_DIR/.response_analysis")
+    assert_equal "$exit_signal" "true"
+}
+
+@test "text mode: YAML colon-block RALPH_STATUS with EXIT_SIGNAL=false does not trigger exit" {
+    local output_file="$LOG_DIR/test_output.log"
+
+    cat > "$output_file" << 'EOF'
+Made progress on the auth module.
+
+RALPH_STATUS:
+  EXIT_SIGNAL: false
+  reason: "More work needed on the session layer"
+EOF
+
+    analyze_response "$output_file" 1
+
+    local exit_signal=$(jq -r '.analysis.exit_signal' "$RALPH_DIR/.response_analysis")
+    assert_equal "$exit_signal" "false"
+}
+
+@test "JSON mode .result field with YAML colon-block RALPH_STATUS triggers exit" {
+    # Claude CLI JSON wrapper format: structured response with .result string
+    # containing a YAML colon-block RALPH_STATUS section. Mirrors the
+    # ".result + ---RALPH_STATUS---" path tested elsewhere; verifies the
+    # extended regex catches the YAML form too.
+    local output_file="$LOG_DIR/test_output.log"
+
+    cat > "$output_file" << 'EOF'
+{
+    "result": "Implementation done.\n\nRALPH_STATUS:\n  EXIT_SIGNAL: true\n  reason: \"Project complete\"\n",
+    "sessionId": "test-session-001"
+}
+EOF
+
+    analyze_response "$output_file" 1
+
+    local exit_signal=$(jq -r '.analysis.exit_signal' "$RALPH_DIR/.response_analysis")
+    assert_equal "$exit_signal" "true"
+}
+
+@test "JSON mode .result field with YAML colon-block EXIT_SIGNAL=false respects continue intent" {
+    # YAML emit can also signal "continue working" — explicit EXIT_SIGNAL: false
+    # must be respected the same way the separator-marker form is.
+    local output_file="$LOG_DIR/test_output.log"
+
+    cat > "$output_file" << 'EOF'
+{
+    "result": "Phase 1 done.\n\nRALPH_STATUS:\n  EXIT_SIGNAL: false\n  reason: \"Phase 2 still pending\"\n",
+    "sessionId": "test-session-002"
+}
+EOF
+
+    analyze_response "$output_file" 1
+
+    local exit_signal=$(jq -r '.analysis.exit_signal' "$RALPH_DIR/.response_analysis")
+    assert_equal "$exit_signal" "false"
+}
+
+@test "text mode: inline RALPH_STATUS: in prose does NOT trigger gate" {
+    # Regression: the regex must anchor to start-of-line so prose mentions of
+    # "RALPH_STATUS:" don't accidentally enter the EXIT_SIGNAL extraction block.
+    # Without anchoring, a sentence like "see the RALPH_STATUS: emit format
+    # documented above" would match the gate. With anchoring, only a block
+    # header at start-of-line matches.
+    local output_file="$LOG_DIR/test_output.log"
+
+    cat > "$output_file" << 'EOF'
+Working on the documentation update.
+
+I added a paragraph that mentions the RALPH_STATUS: emit format inline,
+referencing the canonical layout. No actual block was emitted.
+
+EXIT_SIGNAL: true should also not trigger by itself without a header.
+EOF
+
+    analyze_response "$output_file" 1
+
+    local exit_signal=$(jq -r '.analysis.exit_signal' "$RALPH_DIR/.response_analysis")
+    assert_equal "$exit_signal" "false"
+}
+
+@test "JSON mode .result field with inline RALPH_STATUS: in prose does NOT trigger gate" {
+    # Regression: same line-anchor concern but in the JSON-mode .result path.
+    local output_file="$LOG_DIR/test_output.log"
+
+    cat > "$output_file" << 'EOF'
+{
+    "result": "Updating the README. The RALPH_STATUS: section now describes both formats. EXIT_SIGNAL: true would be a block-emit not an inline reference, so no gate trigger here.",
+    "sessionId": "test-session-prose"
+}
+EOF
+
+    analyze_response "$output_file" 1
+
+    local exit_signal=$(jq -r '.analysis.exit_signal' "$RALPH_DIR/.response_analysis")
+    assert_equal "$exit_signal" "false"
+}
+
+@test "text mode: leading-whitespace RALPH_STATUS: header DOES trigger gate (indented YAML block)" {
+    # The anchor allows optional leading whitespace so indented blocks (e.g.,
+    # nested YAML or quoted in tool output) still match the gate.
+    local output_file="$LOG_DIR/test_output.log"
+
+    cat > "$output_file" << 'EOF'
+Some context lines.
+
+  RALPH_STATUS:
+    EXIT_SIGNAL: true
+    reason: "Done"
+EOF
+
+    analyze_response "$output_file" 1
+
+    local exit_signal=$(jq -r '.analysis.exit_signal' "$RALPH_DIR/.response_analysis")
+    assert_equal "$exit_signal" "true"
+}