CM-72834: Show the value hash of every guardrail finding

A blocked developer only saw severity counts, so a false positive was
unactionable: nothing in the message identified which value tripped the
guardrail. List each distinct finding's type and value hash instead, which
is what `cycode ignore --by-sha` takes.

The hash is safe to display; the value is not. Detections already dropped by
an ignore rule are filtered out upstream in create_local_scan_result, so only
what actually blocked is listed. The two hook messages that interpolated the
summary mid-sentence now put it last, since it spans multiple lines.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Author: Ilanlido

cycode/cli/apps/ai_guardrails/scan/handlers.py

@@ -76,7 +76,8 @@ def handle_before_submit_prompt(ctx: typer.Context, payload: AIHookPayload, poli
             block_reason = SECRETS_BLOCK_REASON_BY_EVENT_TYPE[AiHookEventType.PROMPT]
             if effective_mode == GuardrailsMode.BLOCK:
                 outcome = AIHookOutcome.BLOCKED
-                user_message = f'{violation_summary}. Remove secrets before sending.'
+                # Summary last: it is multi-line, so it must not be interpolated mid-sentence
+                user_message = f'Remove secrets before sending. {violation_summary}'
                 return HookDecision.deny(AiHookEventType.PROMPT, user_message)
             outcome = AIHookOutcome.WARNED
         return HookDecision.allow(AiHookEventType.PROMPT)
@@ -283,7 +284,8 @@ def handle_before_mcp_execution(ctx: typer.Context, payload: AIHookPayload, poli
             event_type=AiHookEventType.MCP_EXECUTION,
             deny_message=lambda v: f'Cycode blocked MCP tool call "{tool}". {v}',
             deny_agent_message='Do not pass secrets to tools. Use secret references (name/id) instead.',
-            ask_message=lambda v: f'{v} in MCP tool call "{tool}". Allow execution?',
+            # Summary last: it is multi-line, so it must not be interpolated mid-sentence
+            ask_message=lambda v: f'Allow MCP tool call "{tool}"? {v}',
             ask_agent_message='Possible secrets detected in tool arguments; proceed with caution.',
         ),
         scan_text=args_text,

cycode/cli/utils/scan_utils.py

@@ -12,6 +12,9 @@
     from cycode.cli.models import LocalScanResult
     from cycode.cyclient.models import ScanConfiguration
 
+# Keeps the hook message readable when a single file trips dozens of detections
+MAX_VIOLATION_DETAIL_LINES = 5
+
 
 def set_issue_detected(ctx: typer.Context, issue_detected: bool) -> None:
     ctx.obj['issue_detected'] = issue_detected
@@ -43,6 +46,33 @@ def generate_unique_scan_id() -> UUID:
     return uuid4()
 
 
+def _build_detection_lines(
+    local_scan_results: list['LocalScanResult'], max_lines: int = MAX_VIOLATION_DETAIL_LINES
+) -> str:
+    """One line per distinct finding: what it is, and the value hash identifying it.
+
+    The value hash is safe to display; the value itself is not. Detections excluded by an existing
+    ignore rule are already gone from `document_detections`, so only what actually blocked is listed.
+    """
+    type_by_sha = {}
+    for local_scan_result in local_scan_results:
+        for document_detections in local_scan_result.document_detections:
+            for detection in document_detections.detections:
+                sha = detection.detection_details.get('sha512')
+                if sha and sha not in type_by_sha:
+                    type_by_sha[sha] = detection.type or detection.message
+
+    if not type_by_sha:
+        return ''
+
+    lines = [f'  - {detection_type}: {sha}' for sha, detection_type in list(type_by_sha.items())[:max_lines]]
+    remaining = len(type_by_sha) - len(lines)
+    if remaining:
+        lines.append(f'  - ...and {remaining} more')
+
+    return '\n' + '\n'.join(lines)
+
+
 def build_violation_summary(local_scan_results: list['LocalScanResult']) -> str:
     """Build violation summary string with severity breakdown and emojis."""
     detections_count = 0
@@ -61,4 +91,5 @@ def build_violation_summary(local_scan_results: list['LocalScanResult']) -> str:
         count = severity_counts[severity]
         severity_parts.append(f'{emoji} {severity.upper()} - {count}')
 
-    return f'Cycode found {detections_count} violations: {" | ".join(severity_parts)}'
+    summary = f'Cycode found {detections_count} violations: {" | ".join(severity_parts)}'
+    return summary + _build_detection_lines(local_scan_results)

tests/cli/commands/ai_guardrails/scan/test_handlers.py

@@ -21,7 +21,9 @@
 )
 from cycode.cli.apps.ai_guardrails.scan.payload import AIHookPayload
 from cycode.cli.apps.ai_guardrails.scan.types import AiHookEventType, AIHookOutcome, BlockReason
-from cycode.cli.models import Document, LocalScanResult
+from cycode.cli.models import Document, DocumentDetections, LocalScanResult
+from cycode.cli.utils.scan_utils import MAX_VIOLATION_DETAIL_LINES, build_violation_summary
+from cycode.cyclient.models import Detection
 
 
 @pytest.fixture
@@ -420,6 +422,60 @@ def test_perform_scan_no_violation_when_all_detections_excluded(mock_ctx: MagicM
     assert scan_id == 'scan-id-123'
 
 
+def _local_scan_result_with_detections(*shas: str) -> LocalScanResult:
+    document = Document(path='prompt-content.txt', content='some content', is_git_diff_format=False)
+    detections = [
+        Detection(
+            detection_type_id='type-id',
+            type='GitHub Token',
+            message='Hardcoded secret',
+            detection_details={'sha512': sha},
+            detection_rule_id='rule-id',
+            severity='High',
+        )
+        for sha in shas
+    ]
+    return LocalScanResult(
+        scan_id='scan-id-123',
+        report_url=None,
+        document_detections=[DocumentDetections(document=document, detections=detections)],
+        issue_detected=True,
+        detections_count=len(detections),
+        relevant_detections_count=len(detections),
+    )
+
+
+def test_violation_summary_lists_one_line_per_distinct_sha() -> None:
+    """A blocked developer needs the value hash to act on the finding (e.g. `cycode ignore --by-sha`)."""
+    summary = build_violation_summary([_local_scan_result_with_detections('sha-aaa', 'sha-bbb', 'sha-aaa')])
+
+    assert 'Cycode found 3 violations' in summary
+    assert 'GitHub Token: sha-aaa' in summary
+    assert 'GitHub Token: sha-bbb' in summary
+    # Repeated values collapse to one line; the hash identifies the value, not the occurrence
+    assert summary.count('sha-aaa') == 1
+
+
+def test_violation_summary_caps_the_detection_lines() -> None:
+    """A file full of detections must not turn the hook message into a wall of text."""
+    shas = [f'sha-{index}' for index in range(MAX_VIOLATION_DETAIL_LINES + 3)]
+
+    summary = build_violation_summary([_local_scan_result_with_detections(*shas)])
+
+    assert summary.count('GitHub Token: ') == MAX_VIOLATION_DETAIL_LINES
+    assert '...and 3 more' in summary
+
+
+def test_violation_summary_omits_lines_without_a_sha() -> None:
+    """Non-secret scan types carry no value hash, so there is nothing to list."""
+    local_scan_result = _local_scan_result_with_detections('sha-aaa')
+    local_scan_result.document_detections[0].detections[0].detection_details = {}
+
+    summary = build_violation_summary([local_scan_result])
+
+    assert 'GitHub Token' not in summary
+
+
 # Tests for handle_before_mcp_execution