opcua-tap
Read-only OPC-UA telemetry + problem surfacing via the ot-aiops MCP server. Preview — validated against an in-process asyncua simulator, NOT live SCADA.
When to use
- An OPC-UA server / PLC gateway (
opc.tcp://host:4840), anonymous or user/pass. - Discover the address space, read tags, sample a node, surface alarms.
When NOT to use (routing)
- Modbus →
modbus-tap; Siemens S7 →s7-tap; Mitsubishi →mc-tap; CNC machine tools →mtconnect-tap; MQTT/Sparkplug/UNS →sparkplug-tap; Rockwell/Allen-Bradley EtherNet/IP →ethernetip-tap. - Cross-protocol "why no data" / alarm-flood / tag-health →
industrial-diagnostics; OEE / downtime / asset inventory →industrial-analytics. - IT/network devices, Kubernetes, hypervisors, backups → not this tool.
Tools
| Tool | Params | Returns |
|---|---|---|
opcua_server_info |
endpoint? |
{state, product_name, namespaces[...]} |
opcua_browse |
node_id="i=85", endpoint?, depth=2 |
[{node_id, browse_name, node_class, depth, parent}] |
opcua_read_node |
node_id, endpoint? |
{value, datatype, source_timestamp, status_code, good} |
opcua_read_many |
node_ids[], endpoint? |
[{node_id, value, ...}] |
opcua_subscribe_sample |
node_id, endpoint?, samples=5, interval_ms=500, timeout_s=30 |
{collected, samples[...]} (bounded) |
opcua_read_alarms |
endpoint?, node_id="i=85", depth=4 |
{active_alarms[...], active_count} |
opcua_read_history |
node_id, endpoint?, start?, end?, max_points=1000 |
{supported, count, values:[{value, source_timestamp, status_code}]} |
health_summary |
endpoint?, node_ids[]?, thresholds? |
{overall, counts, offenders[...]} |
anomaly_scan |
node_id, endpoint?, samples=20, interval_ms=200, sigma=3.0 |
{mean, stddev, outliers[...]} |
opcua_read_history is OPC-UA Historical Access (HDA): raw historical values
over a [start,end] ISO-8601 window (bounded). It returns {supported:false, note}
gracefully when the server does not historize the node. For bounded change-of-value
(only the changes, not every sample) use monitor_changes from industrial-analytics.
Example
opcua_read_node(node_id="ns=2;i=5", endpoint="line1")
→ {"value":85.0,"datatype":"Double","source_timestamp":"2026-06-28T10:00:00Z","good":true}
Setup
ot-aiops init (add an opcua endpoint) · ot-aiops doctor · ot-aiops mcp.
Config: ~/.ot-aiops/config.yaml; secrets encrypted in secrets.enc, unlocked
via OT_AIOPS_MASTER_PASSWORD.
Safety
Read-only. Cert/message security (Sign/Encrypt) is roadmap — only anonymous + user/pass are validated. Endpoint text is sanitized; secrets are never returned. Missing a feature? 缺功能提 issue/PR 欢迎留言.