MCP Policies

Field	Value
Document ID	ASCEND-MCP-002
Version	1.0.0
Last Updated	December 19, 2025
Author	Ascend Engineering Team
Publisher	OW-KAI Technologies Inc.
Classification	Enterprise Client Documentation
Compliance	SOC 2 CC6.1/CC6.2, PCI-DSS 7.1/8.3, HIPAA 164.312, NIST 800-53 AC-2/SI-4

Reading Time: 8 minutes | Skill Level: Intermediate

Overview

MCP (Model Context Protocol) policies define how ASCEND governs interactions between AI models and MCP servers. Configure trust levels, tool restrictions, and approval requirements.

Policy Architecture

Server Trust Levels

Trust Level Definitions

Level	Description	Default Behavior
trusted	Fully vetted, internal servers	Auto-approve most actions
restricted	Partially vetted, limited scope	Require approval for sensitive
sandbox	Untested or external servers	Require approval for all

Configure Server Trust

curl -X PUT "https://pilot.owkai.app/api/mcp/servers/{server_id}/trust" \
  -H "Authorization: Bearer <admin_jwt>" \
  -d '{
    "trust_level": "restricted",
    "reason": "Third-party integration, limited to read operations",
    "allowed_tools": ["search", "read_file"],
    "denied_tools": ["write_file", "execute", "delete"],
    "max_risk_score": 50
  }'

Tool Policies

Create Tool Policy

curl -X POST "https://pilot.owkai.app/api/mcp/policies/tools" \
  -H "Authorization: Bearer <admin_jwt>" \
  -d '{
    "name": "File Write Approval",
    "tool_pattern": "write_*",
    "servers": ["*"],
    "conditions": {
      "parameters.path": {"$regex": "^/sensitive/"}
    },
    "action": "REQUIRE_APPROVAL",
    "approval_level": 2,
    "risk_modifier": 30
  }'

Tool Pattern Matching

Pattern	Matches
*	All tools
read_*	read_file, read_database, etc.
*_database	read_database, write_database
execute	Exact match only

List Tool Policies

curl "https://pilot.owkai.app/api/mcp/policies/tools" \
  -H "Authorization: Bearer <jwt_token>"

Response:

{
  "policies": [
    {
      "policy_id": "pol_mcp_001",
      "name": "File Write Approval",
      "tool_pattern": "write_*",
      "action": "REQUIRE_APPROVAL",
      "is_active": true,
      "priority": 100
    },
    {
      "policy_id": "pol_mcp_002",
      "name": "Block Execute on Sandbox",
      "tool_pattern": "execute",
      "servers": ["sandbox_*"],
      "action": "DENY",
      "is_active": true,
      "priority": 200
    }
  ]
}

Server Policies

Create Server Policy

curl -X POST "https://pilot.owkai.app/api/mcp/policies/servers" \
  -H "Authorization: Bearer <admin_jwt>" \
  -d '{
    "name": "External Server Restrictions",
    "server_pattern": "external_*",
    "default_action": "REQUIRE_APPROVAL",
    "max_requests_per_minute": 10,
    "allowed_ip_ranges": ["10.0.0.0/8"],
    "require_mTLS": true,
    "audit_all_requests": true
  }'

Server Access Control

curl -X PUT "https://pilot.owkai.app/api/mcp/servers/{server_id}/access" \
  -H "Authorization: Bearer <admin_jwt>" \
  -d '{
    "allowed_agents": ["agent_001", "agent_002"],
    "denied_agents": ["untrusted_agent"],
    "require_agent_registration": true,
    "ip_whitelist": ["192.168.1.0/24"]
  }'

Unified Governance

Agent + MCP Unified Policy

curl -X POST "https://pilot.owkai.app/api/governance/unified" \
  -H "Authorization: Bearer <admin_jwt>" \
  -d '{
    "name": "Sensitive Data Access",
    "applies_to": ["agents", "mcp_servers"],
    "conditions": {
      "$or": [
        {"data_category": "pii"},
        {"data_category": "financial"},
        {"data_category": "health"}
      ]
    },
    "action": "REQUIRE_APPROVAL",
    "approval_level": 3,
    "audit_retention_days": 2555
  }'

Policy Evaluation Order

1. Deny policies (highest priority)
2. Server-specific policies
3. Tool-specific policies
4. Trust level defaults
5. Global defaults

Risk Modifiers

Configure MCP Risk Scoring

curl -X PUT "https://pilot.owkai.app/api/mcp/risk-config" \
  -H "Authorization: Bearer <admin_jwt>" \
  -d '{
    "tool_modifiers": {
      "execute": 50,
      "write_*": 30,
      "delete_*": 40,
      "read_*": 5,
      "search": 0
    },
    "server_modifiers": {
      "sandbox": 30,
      "restricted": 15,
      "trusted": 0
    },
    "parameter_modifiers": {
      "contains_pii": 25,
      "external_destination": 20,
      "bulk_operation": 15
    }
  }'

Policy Templates

Apply Security Template

curl -X POST "https://pilot.owkai.app/api/mcp/policies/templates/security-strict/apply" \
  -H "Authorization: Bearer <admin_jwt>"

Security-Strict Template:

• All write operations require approval
• Execute tools blocked by default
• External server requests denied
• Full audit logging

Available Templates

Template	Description
security-strict	Maximum restrictions
security-standard	Balanced security
development	Relaxed for dev/test
compliance-hipaa	HIPAA-compliant settings
compliance-pci	PCI-DSS compliant settings

Conditional Policies

Time-Based Restrictions

curl -X POST "https://pilot.owkai.app/api/mcp/policies" \
  -H "Authorization: Bearer <admin_jwt>" \
  -d '{
    "name": "After Hours Restrictions",
    "conditions": {
      "time_of_day": {"$gte": "18:00", "$lte": "08:00"},
      "day_of_week": {"$nin": ["saturday", "sunday"]}
    },
    "action": "REQUIRE_APPROVAL",
    "approval_level": 3
  }'

Parameter-Based Policies

curl -X POST "https://pilot.owkai.app/api/mcp/policies" \
  -H "Authorization: Bearer <admin_jwt>" \
  -d '{
    "name": "Large Data Export Approval",
    "tool_pattern": "export_*",
    "conditions": {
      "parameters.row_count": {"$gte": 10000}
    },
    "action": "REQUIRE_APPROVAL",
    "approval_level": 2
  }'

Policy Testing

Test Policy Against Request

curl -X POST "https://pilot.owkai.app/api/mcp/policies/test" \
  -H "Authorization: Bearer <admin_jwt>" \
  -d '{
    "server_id": "external_api_server",
    "tool_name": "write_file",
    "parameters": {
      "path": "/sensitive/data.json",
      "content": "test"
    },
    "agent_id": "test_agent"
  }'

Response:

{
  "decision": "REQUIRE_APPROVAL",
  "matched_policies": [
    {
      "policy_id": "pol_mcp_001",
      "name": "File Write Approval",
      "priority": 100
    }
  ],
  "risk_score": 65,
  "risk_factors": [
    {"name": "write_operation", "score": 30},
    {"name": "sensitive_path", "score": 25},
    {"name": "restricted_server", "score": 10}
  ]
}

Audit & Monitoring

MCP Activity Logs

curl "https://pilot.owkai.app/api/mcp/audit?server_id=external_api&days=7" \
  -H "Authorization: Bearer <admin_jwt>"

Response:

{
  "logs": [
    {
      "timestamp": "2025-12-15T10:30:00Z",
      "server_id": "external_api",
      "tool_name": "search",
      "agent_id": "research_agent",
      "decision": "approved",
      "risk_score": 15,
      "response_time_ms": 45
    }
  ],
  "statistics": {
    "total_requests": 150,
    "approved": 145,
    "denied": 5,
    "avg_risk_score": 22
  }
}

Best Practices

1. Start Restrictive

Begin with sandbox trust level and restrictive policies, then relax as confidence grows.

2. Use Specific Patterns

Prefer specific tool patterns over wildcards:

# Better
"tool_pattern": "write_database"

# Less precise
"tool_pattern": "write_*"

3. Layer Policies

Combine server, tool, and parameter policies for defense in depth.

4. Monitor and Adjust

Review audit logs regularly and adjust policies based on actual usage patterns.

Next Steps

• MCP Overview - MCP governance basics
• Server Registration - Register MCP servers
• Smart Rules - General policy configuration

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Document Version: 1.0.0 | Last Updated: December 2025