feat(safety): add Phase D MCP integration and metrics

- Add MCPSafetyWrapper for safe MCP tool execution
- Add MCPToolCall/MCPToolResult models for MCP interactions
- Add SafeToolExecutor context manager
- Add SafetyMetrics collector with Prometheus export support
- Track validations, approvals, rate limits, budgets, and more
- Support for counters, gauges, and histograms

Issue #63

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/app/services/safety/mcp/__init__.py

@@ -0,0 +1,17 @@
+"""MCP safety integration."""
+
+from .integration import (
+    MCPSafetyWrapper,
+    MCPToolCall,
+    MCPToolResult,
+    SafeToolExecutor,
+    create_mcp_wrapper,
+)
+
+__all__ = [
+    "MCPSafetyWrapper",
+    "MCPToolCall",
+    "MCPToolResult",
+    "SafeToolExecutor",
+    "create_mcp_wrapper",
+]

backend/app/services/safety/mcp/integration.py

@@ -0,0 +1,405 @@
+"""
+MCP Safety Integration
+
+Provides safety-aware wrappers for MCP tool execution.
+"""
+
+import asyncio
+import logging
+from collections.abc import Callable
+from dataclasses import dataclass, field
+from datetime import datetime
+from typing import Any, ClassVar, TypeVar
+
+from ..audit import AuditLogger
+from ..emergency import EmergencyControls, get_emergency_controls
+from ..exceptions import (
+    EmergencyStopError,
+    SafetyError,
+)
+from ..guardian import SafetyGuardian, get_safety_guardian
+from ..models import (
+    ActionMetadata,
+    ActionRequest,
+    ActionType,
+    AutonomyLevel,
+    SafetyDecision,
+)
+
+logger = logging.getLogger(__name__)
+
+T = TypeVar("T")
+
+
+@dataclass
+class MCPToolCall:
+    """Represents an MCP tool call."""
+
+    tool_name: str
+    arguments: dict[str, Any]
+    server_name: str | None = None
+    project_id: str | None = None
+    context: dict[str, Any] = field(default_factory=dict)
+
+
+@dataclass
+class MCPToolResult:
+    """Result of an MCP tool execution."""
+
+    success: bool
+    result: Any = None
+    error: str | None = None
+    safety_decision: SafetyDecision = SafetyDecision.ALLOW
+    execution_time_ms: float = 0.0
+    approval_id: str | None = None
+    checkpoint_id: str | None = None
+    metadata: dict[str, Any] = field(default_factory=dict)
+
+
+class MCPSafetyWrapper:
+    """
+    Wraps MCP tool execution with safety checks.
+
+    Features:
+    - Pre-execution validation via SafetyGuardian
+    - Permission checking per tool/resource
+    - Budget and rate limit enforcement
+    - Audit logging of all MCP calls
+    - Emergency stop integration
+    - Checkpoint creation for destructive operations
+    """
+
+    # Tool categories for automatic classification
+    DESTRUCTIVE_TOOLS: ClassVar[set[str]] = {
+        "file_write",
+        "file_delete",
+        "database_mutate",
+        "shell_execute",
+        "git_push",
+        "git_commit",
+        "deploy",
+    }
+
+    READ_ONLY_TOOLS: ClassVar[set[str]] = {
+        "file_read",
+        "database_query",
+        "git_status",
+        "git_log",
+        "list_files",
+        "search",
+    }
+
+    def __init__(
+        self,
+        guardian: SafetyGuardian | None = None,
+        audit_logger: AuditLogger | None = None,
+        emergency_controls: EmergencyControls | None = None,
+    ) -> None:
+        """
+        Initialize MCPSafetyWrapper.
+
+        Args:
+            guardian: SafetyGuardian instance (uses singleton if not provided)
+            audit_logger: AuditLogger instance
+            emergency_controls: EmergencyControls instance
+        """
+        self._guardian = guardian
+        self._audit_logger = audit_logger
+        self._emergency_controls = emergency_controls
+        self._tool_handlers: dict[str, Callable[..., Any]] = {}
+        self._lock = asyncio.Lock()
+
+    async def _get_guardian(self) -> SafetyGuardian:
+        """Get or create SafetyGuardian."""
+        if self._guardian is None:
+            self._guardian = await get_safety_guardian()
+        return self._guardian
+
+    async def _get_emergency_controls(self) -> EmergencyControls:
+        """Get or create EmergencyControls."""
+        if self._emergency_controls is None:
+            self._emergency_controls = await get_emergency_controls()
+        return self._emergency_controls
+
+    def register_tool_handler(
+        self,
+        tool_name: str,
+        handler: Callable[..., Any],
+    ) -> None:
+        """
+        Register a handler for a tool.
+
+        Args:
+            tool_name: Name of the tool
+            handler: Async function to handle the tool call
+        """
+        self._tool_handlers[tool_name] = handler
+        logger.debug("Registered handler for tool: %s", tool_name)
+
+    async def execute(
+        self,
+        tool_call: MCPToolCall,
+        agent_id: str,
+        autonomy_level: AutonomyLevel = AutonomyLevel.MILESTONE,
+        bypass_safety: bool = False,
+    ) -> MCPToolResult:
+        """
+        Execute an MCP tool call with safety checks.
+
+        Args:
+            tool_call: The tool call to execute
+            agent_id: ID of the calling agent
+            autonomy_level: Agent's autonomy level
+            bypass_safety: Bypass safety checks (emergency only)
+
+        Returns:
+            MCPToolResult with execution outcome
+        """
+        start_time = datetime.utcnow()
+
+        # Check emergency controls first
+        emergency = await self._get_emergency_controls()
+        scope = f"agent:{agent_id}"
+        if tool_call.project_id:
+            scope = f"project:{tool_call.project_id}"
+
+        try:
+            await emergency.check_allowed(scope=scope, raise_if_blocked=True)
+        except EmergencyStopError as e:
+            return MCPToolResult(
+                success=False,
+                error=str(e),
+                safety_decision=SafetyDecision.DENY,
+                metadata={"emergency_stop": True},
+            )
+
+        # Build action request
+        action = self._build_action_request(
+            tool_call=tool_call,
+            agent_id=agent_id,
+            autonomy_level=autonomy_level,
+        )
+
+        # Skip safety checks if bypass is enabled
+        if bypass_safety:
+            logger.warning(
+                "Safety bypass enabled for tool: %s (agent: %s)",
+                tool_call.tool_name,
+                agent_id,
+            )
+            return await self._execute_tool(tool_call, action, start_time)
+
+        # Run safety validation
+        guardian = await self._get_guardian()
+        try:
+            guardian_result = await guardian.validate(action)
+        except SafetyError as e:
+            return MCPToolResult(
+                success=False,
+                error=str(e),
+                safety_decision=SafetyDecision.DENY,
+                execution_time_ms=self._elapsed_ms(start_time),
+            )
+
+        # Handle safety decision
+        if guardian_result.decision == SafetyDecision.DENY:
+            return MCPToolResult(
+                success=False,
+                error="; ".join(guardian_result.reasons),
+                safety_decision=SafetyDecision.DENY,
+                execution_time_ms=self._elapsed_ms(start_time),
+            )
+
+        if guardian_result.decision == SafetyDecision.REQUIRE_APPROVAL:
+            # For now, just return that approval is required
+            # The caller should handle the approval flow
+            return MCPToolResult(
+                success=False,
+                error="Action requires human approval",
+                safety_decision=SafetyDecision.REQUIRE_APPROVAL,
+                approval_id=guardian_result.approval_id,
+                execution_time_ms=self._elapsed_ms(start_time),
+            )
+
+        # Execute the tool
+        result = await self._execute_tool(
+            tool_call,
+            action,
+            start_time,
+            checkpoint_id=guardian_result.checkpoint_id,
+        )
+
+        return result
+
+    async def _execute_tool(
+        self,
+        tool_call: MCPToolCall,
+        action: ActionRequest,
+        start_time: datetime,
+        checkpoint_id: str | None = None,
+    ) -> MCPToolResult:
+        """Execute the actual tool call."""
+        handler = self._tool_handlers.get(tool_call.tool_name)
+
+        if handler is None:
+            return MCPToolResult(
+                success=False,
+                error=f"No handler registered for tool: {tool_call.tool_name}",
+                safety_decision=SafetyDecision.ALLOW,
+                execution_time_ms=self._elapsed_ms(start_time),
+            )
+
+        try:
+            if asyncio.iscoroutinefunction(handler):
+                result = await handler(**tool_call.arguments)
+            else:
+                result = handler(**tool_call.arguments)
+
+            return MCPToolResult(
+                success=True,
+                result=result,
+                safety_decision=SafetyDecision.ALLOW,
+                execution_time_ms=self._elapsed_ms(start_time),
+                checkpoint_id=checkpoint_id,
+            )
+
+        except Exception as e:
+            logger.error("Tool execution failed: %s - %s", tool_call.tool_name, e)
+            return MCPToolResult(
+                success=False,
+                error=str(e),
+                safety_decision=SafetyDecision.ALLOW,
+                execution_time_ms=self._elapsed_ms(start_time),
+                checkpoint_id=checkpoint_id,
+            )
+
+    def _build_action_request(
+        self,
+        tool_call: MCPToolCall,
+        agent_id: str,
+        autonomy_level: AutonomyLevel,
+    ) -> ActionRequest:
+        """Build an ActionRequest from an MCP tool call."""
+        action_type = self._classify_tool(tool_call.tool_name)
+
+        metadata = ActionMetadata(
+            agent_id=agent_id,
+            session_id=tool_call.context.get("session_id", ""),
+            project_id=tool_call.project_id or "",
+            autonomy_level=autonomy_level,
+        )
+
+        return ActionRequest(
+            action_type=action_type,
+            tool_name=tool_call.tool_name,
+            arguments=tool_call.arguments,
+            resource=tool_call.arguments.get("path", tool_call.arguments.get("resource")),
+            metadata=metadata,
+        )
+
+    def _classify_tool(self, tool_name: str) -> ActionType:
+        """Classify a tool into an action type."""
+        tool_lower = tool_name.lower()
+
+        # Check destructive patterns
+        if any(d in tool_lower for d in ["write", "create", "delete", "remove", "update"]):
+            if "file" in tool_lower:
+                if "delete" in tool_lower or "remove" in tool_lower:
+                    return ActionType.FILE_DELETE
+                return ActionType.FILE_WRITE
+            if "database" in tool_lower or "db" in tool_lower:
+                return ActionType.DATABASE_MUTATE
+
+        # Check read patterns
+        if any(r in tool_lower for r in ["read", "get", "list", "search", "query"]):
+            if "file" in tool_lower:
+                return ActionType.FILE_READ
+            if "database" in tool_lower or "db" in tool_lower:
+                return ActionType.DATABASE_QUERY
+
+        # Check specific types
+        if "shell" in tool_lower or "exec" in tool_lower or "bash" in tool_lower:
+            return ActionType.SHELL_COMMAND
+
+        if "git" in tool_lower:
+            return ActionType.GIT_OPERATION
+
+        if "http" in tool_lower or "fetch" in tool_lower or "request" in tool_lower:
+            return ActionType.NETWORK_REQUEST
+
+        if "llm" in tool_lower or "ai" in tool_lower or "claude" in tool_lower:
+            return ActionType.LLM_CALL
+
+        # Default to tool call
+        return ActionType.TOOL_CALL
+
+    def _elapsed_ms(self, start_time: datetime) -> float:
+        """Calculate elapsed time in milliseconds."""
+        return (datetime.utcnow() - start_time).total_seconds() * 1000
+
+
+class SafeToolExecutor:
+    """
+    Context manager for safe tool execution with automatic cleanup.
+
+    Usage:
+        async with SafeToolExecutor(wrapper, tool_call, agent_id) as executor:
+            result = await executor.execute()
+            if result.success:
+                # Use result
+            else:
+                # Handle error or approval required
+    """
+
+    def __init__(
+        self,
+        wrapper: MCPSafetyWrapper,
+        tool_call: MCPToolCall,
+        agent_id: str,
+        autonomy_level: AutonomyLevel = AutonomyLevel.MILESTONE,
+    ) -> None:
+        self._wrapper = wrapper
+        self._tool_call = tool_call
+        self._agent_id = agent_id
+        self._autonomy_level = autonomy_level
+        self._result: MCPToolResult | None = None
+
+    async def __aenter__(self) -> "SafeToolExecutor":
+        return self
+
+    async def __aexit__(
+        self,
+        exc_type: type[Exception] | None,
+        exc_val: Exception | None,
+        exc_tb: Any,
+    ) -> bool:
+        # Could trigger rollback here if needed
+        return False
+
+    async def execute(self) -> MCPToolResult:
+        """Execute the tool call."""
+        self._result = await self._wrapper.execute(
+            self._tool_call,
+            self._agent_id,
+            self._autonomy_level,
+        )
+        return self._result
+
+    @property
+    def result(self) -> MCPToolResult | None:
+        """Get the execution result."""
+        return self._result
+
+
+# Factory function
+async def create_mcp_wrapper(
+    guardian: SafetyGuardian | None = None,
+) -> MCPSafetyWrapper:
+    """Create an MCPSafetyWrapper with default configuration."""
+    if guardian is None:
+        guardian = await get_safety_guardian()
+
+    return MCPSafetyWrapper(
+        guardian=guardian,
+        emergency_controls=await get_emergency_controls(),
+    )

backend/app/services/safety/metrics/__init__.py

@@ -0,0 +1,19 @@
+"""Safety metrics collection and export."""
+
+from .collector import (
+    MetricType,
+    MetricValue,
+    SafetyMetrics,
+    get_safety_metrics,
+    record_mcp_call,
+    record_validation,
+)
+
+__all__ = [
+    "MetricType",
+    "MetricValue",
+    "SafetyMetrics",
+    "get_safety_metrics",
+    "record_mcp_call",
+    "record_validation",
+]

backend/app/services/safety/metrics/collector.py

@@ -0,0 +1,416 @@
+"""
+Safety Metrics Collector
+
+Collects and exposes metrics for the safety framework.
+"""
+
+import asyncio
+import logging
+from collections import Counter, defaultdict
+from dataclasses import dataclass, field
+from datetime import datetime
+from enum import Enum
+from typing import Any
+
+logger = logging.getLogger(__name__)
+
+
+class MetricType(str, Enum):
+    """Types of metrics."""
+
+    COUNTER = "counter"
+    GAUGE = "gauge"
+    HISTOGRAM = "histogram"
+
+
+@dataclass
+class MetricValue:
+    """A single metric value."""
+
+    name: str
+    metric_type: MetricType
+    value: float
+    labels: dict[str, str] = field(default_factory=dict)
+    timestamp: datetime = field(default_factory=datetime.utcnow)
+
+
+@dataclass
+class HistogramBucket:
+    """Histogram bucket for distribution metrics."""
+
+    le: float  # Less than or equal
+    count: int = 0
+
+
+class SafetyMetrics:
+    """
+    Collects safety framework metrics.
+
+    Metrics tracked:
+    - Action validation counts (by decision type)
+    - Approval request counts and latencies
+    - Budget usage and remaining
+    - Rate limit hits
+    - Loop detections
+    - Emergency events
+    - Content filter matches
+    """
+
+    def __init__(self) -> None:
+        """Initialize SafetyMetrics."""
+        self._counters: dict[str, Counter[str]] = defaultdict(Counter)
+        self._gauges: dict[str, dict[str, float]] = defaultdict(dict)
+        self._histograms: dict[str, list[float]] = defaultdict(list)
+        self._histogram_buckets: dict[str, list[HistogramBucket]] = {}
+        self._lock = asyncio.Lock()
+
+        # Initialize histogram buckets
+        self._init_histogram_buckets()
+
+    def _init_histogram_buckets(self) -> None:
+        """Initialize histogram buckets for latency metrics."""
+        latency_buckets = [0.01, 0.05, 0.1, 0.25, 0.5, 1.0, 2.5, 5.0, 10.0, float("inf")]
+
+        for name in [
+            "validation_latency_seconds",
+            "approval_latency_seconds",
+            "mcp_execution_latency_seconds",
+        ]:
+            self._histogram_buckets[name] = [
+                HistogramBucket(le=b) for b in latency_buckets
+            ]
+
+    # Counter methods
+
+    async def inc_validations(
+        self,
+        decision: str,
+        agent_id: str | None = None,
+    ) -> None:
+        """Increment validation counter."""
+        async with self._lock:
+            labels = f"decision={decision}"
+            if agent_id:
+                labels += f",agent_id={agent_id}"
+            self._counters["safety_validations_total"][labels] += 1
+
+    async def inc_approvals_requested(self, urgency: str = "normal") -> None:
+        """Increment approval requests counter."""
+        async with self._lock:
+            labels = f"urgency={urgency}"
+            self._counters["safety_approvals_requested_total"][labels] += 1
+
+    async def inc_approvals_granted(self) -> None:
+        """Increment approvals granted counter."""
+        async with self._lock:
+            self._counters["safety_approvals_granted_total"][""] += 1
+
+    async def inc_approvals_denied(self, reason: str = "manual") -> None:
+        """Increment approvals denied counter."""
+        async with self._lock:
+            labels = f"reason={reason}"
+            self._counters["safety_approvals_denied_total"][labels] += 1
+
+    async def inc_rate_limit_exceeded(self, limit_type: str) -> None:
+        """Increment rate limit exceeded counter."""
+        async with self._lock:
+            labels = f"limit_type={limit_type}"
+            self._counters["safety_rate_limit_exceeded_total"][labels] += 1
+
+    async def inc_budget_exceeded(self, budget_type: str) -> None:
+        """Increment budget exceeded counter."""
+        async with self._lock:
+            labels = f"budget_type={budget_type}"
+            self._counters["safety_budget_exceeded_total"][labels] += 1
+
+    async def inc_loops_detected(self, loop_type: str) -> None:
+        """Increment loop detection counter."""
+        async with self._lock:
+            labels = f"loop_type={loop_type}"
+            self._counters["safety_loops_detected_total"][labels] += 1
+
+    async def inc_emergency_events(self, event_type: str, scope: str) -> None:
+        """Increment emergency events counter."""
+        async with self._lock:
+            labels = f"event_type={event_type},scope={scope}"
+            self._counters["safety_emergency_events_total"][labels] += 1
+
+    async def inc_content_filtered(self, category: str, action: str) -> None:
+        """Increment content filter counter."""
+        async with self._lock:
+            labels = f"category={category},action={action}"
+            self._counters["safety_content_filtered_total"][labels] += 1
+
+    async def inc_checkpoints_created(self) -> None:
+        """Increment checkpoints created counter."""
+        async with self._lock:
+            self._counters["safety_checkpoints_created_total"][""] += 1
+
+    async def inc_rollbacks_executed(self, success: bool) -> None:
+        """Increment rollbacks counter."""
+        async with self._lock:
+            labels = f"success={str(success).lower()}"
+            self._counters["safety_rollbacks_total"][labels] += 1
+
+    async def inc_mcp_calls(self, tool_name: str, success: bool) -> None:
+        """Increment MCP tool calls counter."""
+        async with self._lock:
+            labels = f"tool_name={tool_name},success={str(success).lower()}"
+            self._counters["safety_mcp_calls_total"][labels] += 1
+
+    # Gauge methods
+
+    async def set_budget_remaining(
+        self,
+        scope: str,
+        budget_type: str,
+        remaining: float,
+    ) -> None:
+        """Set remaining budget gauge."""
+        async with self._lock:
+            labels = f"scope={scope},budget_type={budget_type}"
+            self._gauges["safety_budget_remaining"][labels] = remaining
+
+    async def set_rate_limit_remaining(
+        self,
+        scope: str,
+        limit_type: str,
+        remaining: int,
+    ) -> None:
+        """Set remaining rate limit gauge."""
+        async with self._lock:
+            labels = f"scope={scope},limit_type={limit_type}"
+            self._gauges["safety_rate_limit_remaining"][labels] = float(remaining)
+
+    async def set_pending_approvals(self, count: int) -> None:
+        """Set pending approvals gauge."""
+        async with self._lock:
+            self._gauges["safety_pending_approvals"][""] = float(count)
+
+    async def set_active_checkpoints(self, count: int) -> None:
+        """Set active checkpoints gauge."""
+        async with self._lock:
+            self._gauges["safety_active_checkpoints"][""] = float(count)
+
+    async def set_emergency_state(self, scope: str, state: str) -> None:
+        """Set emergency state gauge (0=normal, 1=paused, 2=stopped)."""
+        async with self._lock:
+            state_value = {"normal": 0, "paused": 1, "stopped": 2}.get(state, -1)
+            labels = f"scope={scope}"
+            self._gauges["safety_emergency_state"][labels] = float(state_value)
+
+    # Histogram methods
+
+    async def observe_validation_latency(self, latency_seconds: float) -> None:
+        """Observe validation latency."""
+        async with self._lock:
+            self._observe_histogram("validation_latency_seconds", latency_seconds)
+
+    async def observe_approval_latency(self, latency_seconds: float) -> None:
+        """Observe approval latency."""
+        async with self._lock:
+            self._observe_histogram("approval_latency_seconds", latency_seconds)
+
+    async def observe_mcp_execution_latency(self, latency_seconds: float) -> None:
+        """Observe MCP execution latency."""
+        async with self._lock:
+            self._observe_histogram("mcp_execution_latency_seconds", latency_seconds)
+
+    def _observe_histogram(self, name: str, value: float) -> None:
+        """Record a value in a histogram."""
+        self._histograms[name].append(value)
+
+        # Update buckets
+        if name in self._histogram_buckets:
+            for bucket in self._histogram_buckets[name]:
+                if value <= bucket.le:
+                    bucket.count += 1
+
+    # Export methods
+
+    async def get_all_metrics(self) -> list[MetricValue]:
+        """Get all metrics as MetricValue objects."""
+        metrics: list[MetricValue] = []
+
+        async with self._lock:
+            # Export counters
+            for name, counter in self._counters.items():
+                for labels_str, value in counter.items():
+                    labels = self._parse_labels(labels_str)
+                    metrics.append(
+                        MetricValue(
+                            name=name,
+                            metric_type=MetricType.COUNTER,
+                            value=float(value),
+                            labels=labels,
+                        )
+                    )
+
+            # Export gauges
+            for name, gauge_dict in self._gauges.items():
+                for labels_str, gauge_value in gauge_dict.items():
+                    gauge_labels = self._parse_labels(labels_str)
+                    metrics.append(
+                        MetricValue(
+                            name=name,
+                            metric_type=MetricType.GAUGE,
+                            value=gauge_value,
+                            labels=gauge_labels,
+                        )
+                    )
+
+            # Export histogram summaries
+            for name, values in self._histograms.items():
+                if values:
+                    metrics.append(
+                        MetricValue(
+                            name=f"{name}_count",
+                            metric_type=MetricType.COUNTER,
+                            value=float(len(values)),
+                        )
+                    )
+                    metrics.append(
+                        MetricValue(
+                            name=f"{name}_sum",
+                            metric_type=MetricType.COUNTER,
+                            value=sum(values),
+                        )
+                    )
+
+        return metrics
+
+    async def get_prometheus_format(self) -> str:
+        """Export metrics in Prometheus text format."""
+        lines: list[str] = []
+
+        async with self._lock:
+            # Export counters
+            for name, counter in self._counters.items():
+                lines.append(f"# TYPE {name} counter")
+                for labels_str, value in counter.items():
+                    if labels_str:
+                        lines.append(f"{name}{{{labels_str}}} {value}")
+                    else:
+                        lines.append(f"{name} {value}")
+
+            # Export gauges
+            for name, gauge_dict in self._gauges.items():
+                lines.append(f"# TYPE {name} gauge")
+                for labels_str, gauge_value in gauge_dict.items():
+                    if labels_str:
+                        lines.append(f"{name}{{{labels_str}}} {gauge_value}")
+                    else:
+                        lines.append(f"{name} {gauge_value}")
+
+            # Export histograms
+            for name, buckets in self._histogram_buckets.items():
+                lines.append(f"# TYPE {name} histogram")
+                for bucket in buckets:
+                    le_str = "+Inf" if bucket.le == float("inf") else str(bucket.le)
+                    lines.append(f'{name}_bucket{{le="{le_str}"}} {bucket.count}')
+
+                if name in self._histograms:
+                    values = self._histograms[name]
+                    lines.append(f"{name}_count {len(values)}")
+                    lines.append(f"{name}_sum {sum(values)}")
+
+        return "\n".join(lines)
+
+    async def get_summary(self) -> dict[str, Any]:
+        """Get a summary of key metrics."""
+        async with self._lock:
+            total_validations = sum(self._counters["safety_validations_total"].values())
+            denied_validations = sum(
+                v for k, v in self._counters["safety_validations_total"].items()
+                if "decision=deny" in k
+            )
+
+            return {
+                "total_validations": total_validations,
+                "denied_validations": denied_validations,
+                "approval_requests": sum(
+                    self._counters["safety_approvals_requested_total"].values()
+                ),
+                "approvals_granted": sum(
+                    self._counters["safety_approvals_granted_total"].values()
+                ),
+                "approvals_denied": sum(
+                    self._counters["safety_approvals_denied_total"].values()
+                ),
+                "rate_limit_hits": sum(
+                    self._counters["safety_rate_limit_exceeded_total"].values()
+                ),
+                "budget_exceeded": sum(
+                    self._counters["safety_budget_exceeded_total"].values()
+                ),
+                "loops_detected": sum(
+                    self._counters["safety_loops_detected_total"].values()
+                ),
+                "emergency_events": sum(
+                    self._counters["safety_emergency_events_total"].values()
+                ),
+                "content_filtered": sum(
+                    self._counters["safety_content_filtered_total"].values()
+                ),
+                "checkpoints_created": sum(
+                    self._counters["safety_checkpoints_created_total"].values()
+                ),
+                "rollbacks_executed": sum(
+                    self._counters["safety_rollbacks_total"].values()
+                ),
+                "mcp_calls": sum(
+                    self._counters["safety_mcp_calls_total"].values()
+                ),
+                "pending_approvals": self._gauges.get("safety_pending_approvals", {}).get("", 0),
+                "active_checkpoints": self._gauges.get("safety_active_checkpoints", {}).get("", 0),
+            }
+
+    async def reset(self) -> None:
+        """Reset all metrics."""
+        async with self._lock:
+            self._counters.clear()
+            self._gauges.clear()
+            self._histograms.clear()
+            self._init_histogram_buckets()
+
+    def _parse_labels(self, labels_str: str) -> dict[str, str]:
+        """Parse labels string into dictionary."""
+        if not labels_str:
+            return {}
+
+        labels = {}
+        for pair in labels_str.split(","):
+            if "=" in pair:
+                key, value = pair.split("=", 1)
+                labels[key.strip()] = value.strip()
+
+        return labels
+
+
+# Singleton instance
+_metrics: SafetyMetrics | None = None
+_lock = asyncio.Lock()
+
+
+async def get_safety_metrics() -> SafetyMetrics:
+    """Get the singleton SafetyMetrics instance."""
+    global _metrics
+
+    async with _lock:
+        if _metrics is None:
+            _metrics = SafetyMetrics()
+        return _metrics
+
+
+# Convenience functions
+async def record_validation(decision: str, agent_id: str | None = None) -> None:
+    """Record a validation event."""
+    metrics = await get_safety_metrics()
+    await metrics.inc_validations(decision, agent_id)
+
+
+async def record_mcp_call(tool_name: str, success: bool, latency_ms: float) -> None:
+    """Record an MCP tool call."""
+    metrics = await get_safety_metrics()
+    await metrics.inc_mcp_calls(tool_name, success)
+    await metrics.observe_mcp_execution_latency(latency_ms / 1000)