OT-AIops

Governed, vendor-neutral industrial data tap + intelligent troubleshooting for AI agents — across OPC-UA (incl. Historical Access), Modbus-TCP, S7comm, Mitsubishi MC, MTConnect, MQTT/Sparkplug B (full decode), EtherNet/IP (Rockwell/Allen-Bradley Logix), and EtherCAT (pysoem/SOEM fieldbus master) — plus OEE/downtime, active asset-inventory, and change-of-value analytics.

OT-AIops is the OT/industrial member of AIops-tools. It is a factory-level, vendor-neutral, governed data tap that lets an AI agent safely read industrial control systems across many field protocols, plus a cross-protocol intelligence layer that localizes "no data" breaks, analyzes alarm floods (ISA-18.2), ranks unhealthy tags, computes OEE / categorizes downtime, and builds an active asset register. Read-first by design; the few write/command paths are OT-dangerous and gated by MOC discipline. Every tool runs through a vendored governance harness (audit / budget / risk-tier / undo).

⚠️ Preview / v0.3.0 — validated against an in-process OPC-UA simulator (incl. HDA), mocked Modbus/S7/Mitsubishi/EtherNet-IP(pycomm3)/EtherCAT(pysoem) clients, static MTConnect XML fixtures, and synthetic MQTT/Sparkplug B protobuf payloads. NOT tested against live PLCs / SCADA / brokers / Logix controllers / EtherCAT slaves. EtherCAT is hard-real-time and has no software simulator (Linux + root + a real bus only), so it is entirely unverified against hardware. See Safety.

Why

OT is exactly where you want an agent on a tight leash: read first, never blind-write. OT-AIops is the safe, neutral read wedge — one package, one MCP server, many protocols — with governance and an intelligence layer that turns raw reads into actionable diagnoses.

Consolidated capability matrix

57 tools = 51 read + 6 write (MOC). The 51 reads = 41 protocol-read · 4 diagnostics · 5 analytics · 1 self. Run protocols_supported() (or ot-aiops protocols) for the live map.

Per-protocol reference

OPC-UA

• Versions/variants: binary opc.tcp:// via asyncua (sync facade). Security: anonymous + username/password. Certificate message security (Sign / SignAndEncrypt) = roadmap, not validated.
• Connection params: endpoint_url, username (password encrypted), security_mode, security_policy.
• Not supported / planned: cert security; real Alarms & Conditions event subscriptions (alarms are surfaced best-effort by browsing alarm-like boolean nodes).

Modbus-TCP

• Versions/variants: Modbus-TCP via pymodbus. Read function codes FC01 (coils), FC02 (discrete), FC03 (holding), FC04 (input). Write FCs (FC05/06/15/16) = not implemented (read-only preview).
• Connection params: host, port (502), unit_id. Registers are untyped 16-bit words → decode hint (uint16/int16/uint32/int32/float32/raw); big-endian word order.
• Coverage: many domestic 国产 PLCs (汇川 Inovance / 信捷 Xinje / 和利时 Hollysys / 台达 Delta) and any Modbus-TCP vendor.

S7comm (Siemens + 仿西门子 国产)

• Versions/variants: pyS7 (pure-Python, ISO-on-TCP / RFC1006 — no native libsnap7). S7-300/400/1200/1500 and compatible clones. Memory areas DB / M (merker) / I / Q. No protocol auth (CPU gates via "Permit access with PUT/GET").
• Connection params: host, port (102), rack, slot (0/1 for 1200/1500; 0/2 common for 300/400).
• Write: s7_write_db = high risk_tier, MOC, dry-run default, captures BEFORE value + undo.
• Not supported / planned: optimized/symbolic DB access on 1500 with "optimized block access" can require absolute-addressing config on the CPU.

Mitsubishi MC

• Versions/variants: pymcprotocol — MC 3E frame (binary) only. 1E / 4E frames = not supported. PLC types Q / L / QnA / iQ-R / iQ-L. Devices: D/W/R (word), M/X/Y/B (bit).
• Connection params: host, port (5007 default; set to the module's open MC port), plctype.
• Write: mc_write_words = high/MOC/dry-run default, captures BEFORE + undo.

MTConnect (ALL CNC machine tools)

• Versions/variants: agent REST + XML (requests + xml.etree), namespace-agnostic (parses MTConnect 1.x Devices/Streams/Assets schemas). Endpoints: /probe, /current, /sample, /assets. Read-only by specification. XML parsing is hardened (DTD/entity declarations rejected — XXE/billion-laughs defense).
• Connection params: agent_url (e.g. http://host:5000).
• Not supported / planned: MTConnect streaming (long-poll interval=); only bounded count= samples.

MQTT / Sparkplug B / UNS

• Versions/variants: paho-mqtt — MQTT 3.1.1 & 5. Sparkplug B topic convention spBv1.0/{group}/{type}/{edge}/[device] (NBIRTH/DBIRTH/NDATA/DDATA/NDEATH/DDEATH/STATE). TLS + username/password supported.
• Full Sparkplug B decode (no optional extra): payloads are protobuf-decoded with a vendored, byte-for-byte copy of the official Eclipse Tahu sparkplug_b.proto generated module (depends only on protobuf). Per metric you get name, alias (resolved to its name via the BIRTH model), datatype (Int8…Int64/UInt…/Float/Double/Boolean/String/DateTime/Text/UUID/DataSet/Bytes/File/Template/PropertySet…), value, timestamp, and the is_historical / is_null flags. A birth/death + seq model tracks node/device online state (NBIRTH/DBIRTH ↔ NDEATH/DDEATH), builds the alias→name map from BIRTH, applies NDATA/DDATA by alias, and flags seq gaps / out-of-order. Primary-host awareness: STATE/<host_id> topics surface in sparkplug_node_list. sparkplug_decode_payload decodes a single raw payload (base64/hex) offline.
• Connection params: host/broker, port (1883 / 8883 TLS), topic, use_tls, username (password encrypted).
• Command: mqtt_publish = high/MOC/dry-run default; a published command has no automatic inverse.

EtherNet/IP (Rockwell / Allen-Bradley)

• Supported: ControlLogix / CompactLogix (and GuardLogix) via CIP / EtherNet-IP using pycomm3 (pure-Python — no native deps). Tag-based, symbolic access: read/write tags by name (Conveyor.Speed, Array[3], Program:Main.X) and discover the controller's tag list at runtime (eip_list_tags, the headline feature). eip_controller_info reads the controller identity.
• Connection params: host, slot (0 for CompactLogix; the CPU slot for a ControlLogix chassis), port (44818). protocol: ethernetip (alias eip).
• Write: eip_write_tag = high risk_tier, MOC, dry-run default, captures BEFORE value + undo.
• Not supported / planned: PLC-5 / SLC-500 (PCCC) and Micro800 are not supported = roadmap (Logix tag model only).

EtherCAT (pysoem / SOEM fieldbus master)

• Supported: a real EtherCAT master via pysoem (the Python binding for the SOEM C stack). CoE SDO read (ethercat_read_sdo, acyclic mailbox upload) + SDO write (ethercat_write_sdo, download), input PDO read (ethercat_read_pdo, one bounded cyclic snapshot), bus scan / slave enumeration (ethercat_slaves, ethercat_slave_info — identity, SM/FMMU mapping, object-dictionary summary), master/working-counter state (ethercat_master_state), and AL-state transitions INIT↔PREOP↔SAFEOP↔OP (ethercat_set_state).

• HARD REQUIREMENTS (no way around them): Linux, root or CAP_NET_RAW, a dedicated NIC cabled to the bus, and real EtherCAT slave hardware. pysoem is an OPTIONAL extra: pip install ot-aiops[ethercat] — the base package installs and imports without it, and every EtherCAT tool then degrades to a teaching error (never crashes, never imports pysoem at module load).

• NOT supported: no software simulator exists (unlike OPC-UA / Modbus) — EtherCAT is hardware-only and not testable in mock-only CI; macOS is unsupported. EoE / FoE / SoE mailbox protocols and full PDO-mapping decode/expansion = roadmap.

• Connection params: nic (the dedicated interface name, e.g. eth1; alias interface), optional expected_slaves (a sanity check vs the bus scan). protocol: ethercat.

• Operations matrix:

  Tool	Op	R/W	risk	Capture/notes
  ethercat_master_state	master + WKC state, slave count	R	low	expected vs found
  ethercat_slaves	bus scan / enumerate	R	low	index/vendor/product/rev/addr/AL-state
  ethercat_slave_info	one-slave detail	R	low	SM/FMMU + OD summary
  ethercat_read_sdo	CoE SDO upload	R	low	hex + uint interpretation
  ethercat_read_pdo	input PDO snapshot	R	low	single cycle, never loops
  ethercat_write_sdo	CoE SDO download	W	high/MOC	before-value (SDO read-back) + undo
  ethercat_set_state	AL-state transition	W	high/MOC	before-state + undo; can start/stop motion

• Write/state safety: ethercat_write_sdo (hex little-endian bytes) and ethercat_set_state are high risk_tier, MOC, dry-run by default, capture the BEFORE value/state for undo, and need a CLI double-confirm. Changing EtherCAT state can START or STOP machine motion — treat with extreme care. 未经授权勿对生产控制系统写入.

OEE / downtime analytics (cross-protocol, read-only)

• oee_compute — OEE = Availability × Performance × Quality from production inputs (planned time, run time, ideal cycle, total/good counts). Each factor is reported raw + clamped to [0,1]; a capped performance >1.0 flags an optimistic ideal cycle.
• downtime_events — auto-detects running→stopped transitions in a {timestamp, state} series and produces stoppage events with durations, categorized (changeover / material / mechanical / quality / break / unknown, by keyword heuristics or a {state: category} override).
• oee_multidim — aggregates OEE across machine × part × shift (or any dimensions) from labelled records → the matrix + worst performers.
• Operate over provided/collected inputs (fully testable without a plant). mtconnect_oee_snapshot surfaces the live MTConnect availability/execution inputs that feed these.

Active asset inventory / fingerprint (read-only)

• asset_inventory — for each configured (or named) endpoint, actively connects with our own protocol client and reads its identity call (S7 s7_cpu_info, EtherNet/IP eip_controller_info, OPC-UA server build info, Modbus Device Identification FC43/0x2B, Mitsubishi CPU type, MTConnect device model), aggregating vendor / model / firmware / serial / reachable / last_seen into an asset register.
• Honest scope (IEC 62443-flavored): this is ACTIVE fingerprinting via our client connections, NOT passive SPAN/tap discovery — it only finds devices we are configured to reach and adds light load to each. Passive, traffic-mirroring discovery is roadmap.

OPC-UA Historical Access (HDA)

• opcua_read_history — reads stored historical values for a node over a [start,end] ISO-8601 window via the server's HistoryRead service (asyncua read_raw_history), bounded by max_points (≤2000). Returns {supported:false, note} gracefully when the server does not historize the node (no crash). Read-only.

Change-of-value (CoV) monitor

• monitor_changes — bounded deadband report: polls a point and returns only the value CHANGES (with timestamps), not every sample. Works over OPC-UA / Modbus / S7 / Mitsubishi MC / EtherNet-IP. Never an infinite loop — hard-capped by both duration_s (≤120) and max_changes (≤500). Read-only.

Install

uv tool install ot-aiops      # or: pip install ot-aiops
ot-aiops init                 # interactive: add endpoints, store passwords encrypted
ot-aiops doctor               # config + per-protocol connectivity probe (point at simulators)
ot-aiops protocols            # the capability map

Master password

Secrets (per-endpoint passwords, MQTT credentials) are never stored in plaintext — they live in ~/.ot-aiops/secrets.enc (Fernet + scrypt). Export OT_AIOPS_MASTER_PASSWORD so the MCP server/CLI can unlock non-interactively:

export OT_AIOPS_MASTER_PASSWORD='…'

Example ~/.ot-aiops/config.yaml (one block per protocol)

endpoints:
  - name: line1
    protocol: opcua
    endpoint_url: opc.tcp://plc.lan:4840
    # username: operator           # password stored encrypted via init/secret set
    tags:
      - { ref: "ns=2;i=5", label: temp, warn_high: 70, alarm_high: 90 }
  - name: plc2
    protocol: modbus
    host: 10.0.0.5
    port: 502
    unit_id: 1
  - name: press1
    protocol: s7
    host: 10.0.0.6
    rack: 0
    slot: 1                        # S7-1200/1500
  - name: cell3
    protocol: mc
    host: 10.0.0.7
    port: 5007
    plctype: iQ-R
  - name: vmc1
    protocol: mtconnect
    agent_url: http://10.0.0.8:5000
  - name: uns
    protocol: mqtt
    host: broker.lan
    use_tls: true                  # → port 8883
    topic: spBv1.0/#
    # username: edge1              # password stored encrypted
  - name: cell5
    protocol: ethernetip           # alias: eip
    host: 10.0.0.9
    slot: 0                        # 0 for CompactLogix; CPU slot for ControlLogix
  - name: bus1
    protocol: ethercat             # Linux + root/CAP_NET_RAW + pip install ot-aiops[ethercat]
    nic: eth1                      # dedicated NIC cabled to the EtherCAT bus
    expected_slaves: 8             # optional sanity check vs the bus scan

ot-aiops init walkthrough (per protocol)

$ ot-aiops init
Step 1 — master password: ********
Step 2 — add an endpoint
  Endpoint name (e.g. line1): press1
  Protocol ('opcua','modbus','s7','mc','mtconnect','mqtt') [opcua]: s7
  S7 PLC host (IP/FQDN): 10.0.0.6
  Port [102]: 102
  Rack (0 for S7-1200/1500) [0]: 0
  Slot (1 for S7-1200/1500, 2 for S7-300/400) [1]: 1
✓ Saved endpoint 'press1'.

(MQTT prompts add TLS/topic/username; MTConnect prompts for agent_url; EtherCAT prompts for the nic + expected_slaves and warns about the Linux/root/NIC/optional-extra requirement; OPC-UA/MQTT prompt for a hidden password stored encrypted.)

Test against a simulator (per protocol)

• OPC-UA — an asyncua demo server (the test suite runs a real in-process one).
• Modbus — ModbusPal or a pymodbus server simulator.
• S7 — a pyS7/snap7 S7 server sim (Snap7 server) on :102.
• MTConnect — the public MTConnect demo agent, or a local agent.
• MQTT — a local mosquitto broker (+ a Sparkplug edge for SpB topics).
• Mitsubishi MC — GX Simulator / an MC 3E server sim.
• EtherNet/IP — a pycomm3-compatible CIP/Logix simulator (or a spare CompactLogix).
• EtherCAT — no simulator exists (hard-real-time, raw-Ethernet). Validate only on Linux, as root / with CAP_NET_RAW, on a dedicated NIC wired to real slaves (e.g. a Beckhoff EK1100 coupler + EL terminals). ot-aiops doctor reports a clear "needs Linux/root/NIC/pysoem" status off the bus rather than failing.

Usage

CLI (read)

ot-aiops opcua read "ns=2;i=5" -e line1
ot-aiops modbus holding 0 -e plc2 --count 4 --decode float32
ot-aiops s7 read-db 1 REAL 4 -e press1 --count 2
ot-aiops mc words D100 -e cell3 --count 8
ot-aiops mtconnect oee -e vmc1
ot-aiops mqtt nodes -e uns --timeout-s 15
ot-aiops eip tags -e cell5                           # Logix tag discovery
ot-aiops eip read "Conveyor.Speed" -e cell5
ot-aiops ethercat slaves -e bus1                     # EtherCAT bus scan (Linux+root)
ot-aiops ethercat read-sdo 0 4120 --subindex 1 -e bus1   # CoE SDO 0x1018:1
ot-aiops opcua history "ns=2;i=5" -e line1 --start 2026-06-28T08:00:00Z   # HDA
ot-aiops opcua monitor "ns=2;i=5" -e line1 --duration-s 20 --deadband 0.5 # CoV
ot-aiops diag dataflow -e line1 --ref "ns=2;i=5" --freshness-s 30
ot-aiops analytics oee 28800 25200 2.0 12000 11800   # OEE = A×P×Q
ot-aiops analytics asset -e press1 -e cell5           # active asset register

CLI (write — dry-run by default, double-confirm on --apply)

ot-aiops s7 write-db 1 INT 0 42 -e press1            # dry-run preview
ot-aiops s7 write-db 1 INT 0 42 -e press1 --apply    # double-confirm prompt
ot-aiops mqtt publish factory/line1/cmd '{"setpoint":50}' -e uns --apply
ot-aiops eip write-tag Setpoint 42 -e cell5 --apply  # Logix tag write (double-confirm)
ot-aiops ethercat write-sdo 0 24698 e8030000 -e bus1 --apply   # CoE SDO 0x607A download
ot-aiops ethercat set-state PREOP --slave 0 -e bus1 --apply     # AL-state (can stop motion!)

MCP tool calls (JSON args → sample structured return)

s7_read_db:

{ "db": 1, "dtype": "REAL", "start": 4, "endpoint": "press1", "count": 2 }

{ "endpoint": "press1", "area": "DB", "db": 1, "dtype": "REAL", "start": 4,
  "count": 2, "items": [ {"address": "DB1,REAL4", "value": 20.5},
                         {"address": "DB1,REAL8", "value": 4.2} ] }

s7_write_db (dry-run):

{ "db": 1, "dtype": "INT", "start": 0, "value": 42, "endpoint": "press1" }

{ "address": "DB1,INT0", "dry_run": true, "before": 7, "would_write": 42,
  "note": "Dry run — nothing written. Re-run with dry_run=false AND a recorded approver…" }

mtconnect_oee_snapshot:

{ "availability": "AVAILABLE", "execution": "ACTIVE", "controller_mode": "AUTOMATIC",
  "program": "O1234", "available": true, "running": true, "verdict": "running" }

eip_read_tag:

{ "tag": "Conveyor.Speed", "endpoint": "cell5" }

{ "endpoint": "cell5", "tag": "Conveyor.Speed", "value": 1500.0, "type": "REAL",
  "error": "", "good": true }

eip_write_tag (dry-run):

{ "tag": "Setpoint", "value": 42, "endpoint": "cell5" }

{ "endpoint": "cell5", "tag": "Setpoint", "dry_run": true, "before": 7,
  "would_write": 42, "note": "Dry run — nothing written. Re-run with dry_run=false AND a recorded approver…" }

ethercat_read_sdo (CoE SDO upload):

{ "slave": 0, "index": 4120, "subindex": 1, "endpoint": "bus1" }

{ "endpoint": "bus1", "slave": 0, "index": "0x1018", "subindex": 1,
  "byte_length": 4, "hex": "9a020000", "as_uint": 666 }

ethercat_set_state (dry-run; can start/stop motion):

{ "state": "OP", "slave": 0, "endpoint": "bus1" }

{ "endpoint": "bus1", "scope": "slave[0]", "dry_run": true, "before": "SAFEOP",
  "would_request": "OP", "note": "Dry run — no state change. … Changing EtherCAT state can start/stop machine motion." }

sparkplug_decode_payload (full SpB metric decode):

{ "payload": "CAESBwoDYWJjEAE=", "encoding": "base64" }

{ "encoding": "sparkplug_b", "seq": 0, "metric_count": 2, "historical_count": 0,
  "metrics": [ {"name": "Temperature", "alias": 1, "datatype": "Double", "value": 21.5,
                "is_historical": false, "is_null": false} ] }

oee_compute:

{ "planned_time_s": 28800, "run_time_s": 25200, "ideal_cycle_time_s": 2.0,
  "total_count": 12000, "good_count": 11800 }

{ "availability": {"raw": 0.875, "value": 0.875, "capped": false},
  "performance": {"value": 0.952381}, "quality": {"value": 0.983333},
  "oee": 0.819444, "oee_pct": 81.94 }

asset_inventory (active fingerprint):

{ "endpoints": ["press1", "cell5"] }

{ "asset_count": 2, "reachable_count": 2, "method": "active_fingerprint",
  "assets": [ {"endpoint": "press1", "protocol": "s7", "vendor": "Siemens/compatible",
               "model": "CPU 1511-1 PN", "firmware": "2.8", "reachable": true,
               "last_seen": "2026-06-28T10:00:00+00:00"} ] }

Diagnostics (multi-dimensional JSON for an agent to visualize)

diagnose_dataflow(endpoint="line1", ref="ns=2;i=5", freshness_threshold_s=30):

{ "verdict": "comms_ok_value_stale",
  "diagnosis": "Connected with good status, but the value is STALE (age 412s > 30s) — the source/field upstream has stopped updating this point.",
  "recommended_action": "Trace upstream: the device serves the last value fine, so suspect the source/scanner/field signal that should refresh it.",
  "hops": [ {"hop":"connect","protocol":"opcua","ok":true,"detail":"OPC-UA state=0"},
            {"hop":"read_tag","ref":"ns=2;i=5","ok":true,"detail":"5.0"},
            {"hop":"freshness","evaluated":true,"stale":true,"age_seconds":412.0} ] }

alarm_bad_actors(events=[…]):

{ "event_count": 55, "window_minutes": 0.82, "alarms_per_hour": 4024.4,
  "isa_18_2": {"ok_max":6,"manageable_max":12,"flood_min":30},
  "flood_verdict": "flood",
  "priority_distribution": {"high":50,"low":5},
  "pareto_sources_for_80pct": ["FIC101"],
  "top_offenders": [ {"source":"FIC101","count":50,"share_pct":90.9,"chattering":true,"standing":false} ],
  "chattering": ["FIC101"], "standing": [] }

tag_health(tags=[…]):

{ "evaluated": 4, "overall": "alarm", "offender_count": 3,
  "offenders": [ {"ref":"hot","latest":99,"flags":["out_of_range_alarm"],"severity":3},
                 {"ref":"flat","latest":5,"flags":["flatline"],"severity":2},
                 {"ref":"bad","latest":null,"flags":["bad_quality"],"severity":3} ] }

MCP server

ot-aiops mcp        # stdio transport; or the `ot-aiops-mcp` entry point

Safety & governance

• Read-first. 51 of 57 tools are read-only. The 6 write/command tools (s7_write_db, mc_write_words, mqtt_publish, eip_write_tag, ethercat_write_sdo, ethercat_set_state) are OT-dangerous: governed at high risk_tier, off by default (dry-run), capture the BEFORE value/state for undo, require a double-confirm in the CLI, and (via policy) a recorded approver — MOC discipline. ethercat_set_state can START or STOP machine motion. 未经授权勿对生产控制系统写入.
• Do not point this at a production control system without authorization. OT networks are safety-critical; even reads add load. Test against a simulator first.
• All endpoint-returned text is sanitized (prompt-injection defense); secrets are never returned by any tool; MTConnect XML is parsed with DTD/entity declarations refused.
• Every tool runs through the vendored governance harness: SQLite audit (~/.ot-aiops/audit.db), token/call budget + runaway breaker, risk-tier gate, undo recording.

Roadmap

• EtherNet/IP PLC-5 / SLC-500 (PCCC) and Micro800 support (Logix tags are done in 0.2.0).
• Passive asset discovery (SPAN/tap, no connections) alongside today's active fingerprint.
• EtherCAT EoE / FoE / SoE mailbox protocols and full PDO-mapping decode (CoE SDO/PDO read+write and AL-state landed in 0.3.0 via the optional pysoem extra).
• OPC-UA certificate security + real Alarms & Conditions subscriptions.
• MTConnect streaming long-poll; Sparkplug B DataSet/Template deep expansion.

Missing a protocol, device, or feature? 缺功能提 issue/PR 欢迎留言 — open a GitHub issue or PR.

License

MIT © wei