# update_acl

Update an existing ACL rule (requires SCRIPTING_ENABLED=true)

Agent View of the PolicyLayer registry record for `update_acl`. HTML page: https://policylayer.com/tools/servicenow-mcp-server/update-acl

## Facts

- Tool: `update_acl`
- Server: ServiceNow MCP Server (`@aartiq/servicenow-mcp`) — https://policylayer.com/tools/servicenow-mcp-server.md
- Install: `npx -y @aartiq/servicenow-mcp`
- Homepage: https://github.com/aartiq/servicenow-mcp
- Risk category: Write (Medium risk)
- Registry record: grade F, identity verified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Rate-limited

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "update_acl",
    "arguments": {}
  }
}
```

## Why update_acl is rated Medium

This tool modifies Access Control List (ACL) rules, which control permissions and access to resources in ServiceNow. While not irreversible (ACLs can be updated again), misconfiguration could grant unintended access or lock out legitimate users, making it a Write operation with high severity due to its potential impact on system security posture and access governance.

From the tool's own definition: "Tool name 'update_acl' and description 'Update an existing ACL rule' indicates modification of access control rules. The description notes '(requires SCRIPTING_ENABLED=true)', indicating this is a sensitive system configuration operation."

## Use case

AI agents use update_acl to create or update resources in ServiceNow MCP Server, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your ServiceNow MCP Server environment.

## Recommended policy (PolicyLayer)

Verdict: **Rate-limited**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches ServiceNow MCP Server:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "update_acl": {
      "limits": [
        {
          "counter": "update_acl_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## Other tools on ServiceNow MCP Server (364)

- `delete_attachment` — Destructive — https://policylayer.com/tools/servicenow-mcp-server/delete-attachment.md
- `delete_system_property` — Destructive — https://policylayer.com/tools/servicenow-mcp-server/delete-system-property.md
- `delete_uib_page` — Destructive — https://policylayer.com/tools/servicenow-mcp-server/delete-uib-page.md
- `remove_user_from_group` — Destructive — https://policylayer.com/tools/servicenow-mcp-server/remove-user-from-group.md
- `rollback_deployment` — Destructive — https://policylayer.com/tools/servicenow-mcp-server/rollback-deployment.md
- `commit_changeset` — Execute — https://policylayer.com/tools/servicenow-mcp-server/commit-changeset.md
- `create_business_rule` — Execute — https://policylayer.com/tools/servicenow-mcp-server/create-business-rule.md
- `create_flow_action` — Execute — https://policylayer.com/tools/servicenow-mcp-server/create-flow-action.md
- `create_scheduled_job` — Execute — https://policylayer.com/tools/servicenow-mcp-server/create-scheduled-job.md
- `create_script_include` — Execute — https://policylayer.com/tools/servicenow-mcp-server/create-script-include.md
- `create_ui_action` — Execute — https://policylayer.com/tools/servicenow-mcp-server/create-ui-action.md
- `execute_background_script` — Execute — https://policylayer.com/tools/servicenow-mcp-server/execute-background-script.md
- `fire_event` — Execute — https://policylayer.com/tools/servicenow-mcp-server/fire-event.md
- `ml_detect_anomalies` — Execute — https://policylayer.com/tools/servicenow-mcp-server/ml-detect-anomalies.md
- `ml_train_anomaly_detector` — Execute — https://policylayer.com/tools/servicenow-mcp-server/ml-train-anomaly-detector.md
- `ml_train_change_risk` — Execute — https://policylayer.com/tools/servicenow-mcp-server/ml-train-change-risk.md
- `ml_train_incident_classifier` — Execute — https://policylayer.com/tools/servicenow-mcp-server/ml-train-incident-classifier.md
- `publish_changeset` — Execute — https://policylayer.com/tools/servicenow-mcp-server/publish-changeset.md
- `run_aggregate_query` — Execute — https://policylayer.com/tools/servicenow-mcp-server/run-aggregate-query.md
- `run_atf_suite` — Execute — https://policylayer.com/tools/servicenow-mcp-server/run-atf-suite.md
- `run_atf_test` — Execute — https://policylayer.com/tools/servicenow-mcp-server/run-atf-test.md
- `run_discovery_scan` — Execute — https://policylayer.com/tools/servicenow-mcp-server/run-discovery-scan.md
- `run_security_playbook` — Execute — https://policylayer.com/tools/servicenow-mcp-server/run-security-playbook.md
- `run_transform_map` — Execute — https://policylayer.com/tools/servicenow-mcp-server/run-transform-map.md
- `scan_vulnerabilities` — Execute — https://policylayer.com/tools/servicenow-mcp-server/scan-vulnerabilities.md
- `switch_update_set` — Execute — https://policylayer.com/tools/servicenow-mcp-server/switch-update-set.md
- `test_flow` — Execute — https://policylayer.com/tools/servicenow-mcp-server/test-flow.md
- `trigger_agentic_playbook` — Execute — https://policylayer.com/tools/servicenow-mcp-server/trigger-agentic-playbook.md
- `trigger_flow` — Execute — https://policylayer.com/tools/servicenow-mcp-server/trigger-flow.md
- `trigger_scheduled_job` — Execute — https://policylayer.com/tools/servicenow-mcp-server/trigger-scheduled-job.md
- …and 334 more: https://policylayer.com/tools/servicenow-mcp-server.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=servicenow-mcp-server · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/servicenow-mcp-server