OPC UA MCP Server

What you can do with it

We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.

• Connection: Runs on your computer
• Transport: stdio
• Category: Other
• You need to fill in: OPCUA_SERVER_URL, OPCUA_CLIENT_KEY, OPCUA_PASSWORD, OPCUA_USER_KEY, OPCUA_PROFILE, OPCUA_AUDIT_CHAIN_KEY_FILE

Install

Pick the AI app you use, then copy the settings.

You need

• npmNode.js installed (for the npx command)

Which app do you use?

{
  "mcpServers": {
    "opcua": {
      "command": "npx",
      "args": [
        "-y",
        "opcua-mcp-server"
      ],
      "env": {
        "OPCUA_SERVER_URL": "your-value",
        "OPCUA_PYTHON_BACKEND": "your-value",
        "OPCUA_SECURITY_POLICY": "your-value",
        "OPCUA_SECURITY_MODE": "your-value",
        "OPCUA_CLIENT_CERT": "your-value",
        "OPCUA_CLIENT_KEY": "your-value",
        "OPCUA_APPLICATION_URI": "your-value",
        "OPCUA_SERVER_CERT": "your-value",
        "OPCUA_SERVER_TRUST_STORE": "your-value",
        "OPCUA_SERVER_APPLICATION_URI": "your-value",
        "OPCUA_USERNAME": "your-value",
        "OPCUA_PASSWORD": "your-value",
        "OPCUA_USER_CERT": "your-value",
        "OPCUA_USER_KEY": "your-value",
        "OPCUA_PROFILE": "your-value",
        "OPCUA_POLICY_FILE": "your-value",
        "OPCUA_ALLOWED_TOOLS": "your-value",
        "OPCUA_ALLOWED_WRITE_NODES": "your-value",
        "OPCUA_ALLOWED_METHODS": "your-value",
        "OPCUA_ALLOW_ACKNOWLEDGE_ALARMS": "your-value",
        "OPCUA_ALLOW_INSECURE_CONTROL": "your-value",
        "OPCUA_ALLOW_UNVERIFIED_SERVER_CONTROL": "your-value",
        "OPCUA_ALLOW_OUT_OF_RANGE_WRITES": "your-value",
        "OPCUA_AUDIT_FILE": "your-value",
        "OPCUA_AUDIT_FSYNC": "your-value",
        "OPCUA_AUDIT_CHAIN": "your-value",
        "OPCUA_AUDIT_CHAIN_KEY_FILE": "your-value",
        "OPCUA_OPERATOR_ID": "your-value",
        "OPCUA_RECONNECT_INITIAL_DELAY_MS": "your-value",
        "OPCUA_RECONNECT_MAX_DELAY_MS": "your-value",
        "OPCUA_RECONNECT_MAX_RETRY": "your-value",
        "OPCUA_SESSION_TIMEOUT_MS": "your-value"
      }
    }
  }
}

claude mcp add opcua --env OPCUA_SERVER_URL=your-value --env OPCUA_PYTHON_BACKEND=your-value --env OPCUA_SECURITY_POLICY=your-value --env OPCUA_SECURITY_MODE=your-value --env OPCUA_CLIENT_CERT=your-value --env OPCUA_CLIENT_KEY=your-value --env OPCUA_APPLICATION_URI=your-value --env OPCUA_SERVER_CERT=your-value --env OPCUA_SERVER_TRUST_STORE=your-value --env OPCUA_SERVER_APPLICATION_URI=your-value --env OPCUA_USERNAME=your-value --env OPCUA_PASSWORD=your-value --env OPCUA_USER_CERT=your-value --env OPCUA_USER_KEY=your-value --env OPCUA_PROFILE=your-value --env OPCUA_POLICY_FILE=your-value --env OPCUA_ALLOWED_TOOLS=your-value --env OPCUA_ALLOWED_WRITE_NODES=your-value --env OPCUA_ALLOWED_METHODS=your-value --env OPCUA_ALLOW_ACKNOWLEDGE_ALARMS=your-value --env OPCUA_ALLOW_INSECURE_CONTROL=your-value --env OPCUA_ALLOW_UNVERIFIED_SERVER_CONTROL=your-value --env OPCUA_ALLOW_OUT_OF_RANGE_WRITES=your-value --env OPCUA_AUDIT_FILE=your-value --env OPCUA_AUDIT_FSYNC=your-value --env OPCUA_AUDIT_CHAIN=your-value --env OPCUA_AUDIT_CHAIN_KEY_FILE=your-value --env OPCUA_OPERATOR_ID=your-value --env OPCUA_RECONNECT_INITIAL_DELAY_MS=your-value --env OPCUA_RECONNECT_MAX_DELAY_MS=your-value --env OPCUA_RECONNECT_MAX_RETRY=your-value --env OPCUA_SESSION_TIMEOUT_MS=your-value -- npx -y opcua-mcp-server

{
  "mcpServers": {
    "opcua": {
      "command": "npx",
      "args": [
        "-y",
        "opcua-mcp-server"
      ],
      "env": {
        "OPCUA_SERVER_URL": "your-value",
        "OPCUA_PYTHON_BACKEND": "your-value",
        "OPCUA_SECURITY_POLICY": "your-value",
        "OPCUA_SECURITY_MODE": "your-value",
        "OPCUA_CLIENT_CERT": "your-value",
        "OPCUA_CLIENT_KEY": "your-value",
        "OPCUA_APPLICATION_URI": "your-value",
        "OPCUA_SERVER_CERT": "your-value",
        "OPCUA_SERVER_TRUST_STORE": "your-value",
        "OPCUA_SERVER_APPLICATION_URI": "your-value",
        "OPCUA_USERNAME": "your-value",
        "OPCUA_PASSWORD": "your-value",
        "OPCUA_USER_CERT": "your-value",
        "OPCUA_USER_KEY": "your-value",
        "OPCUA_PROFILE": "your-value",
        "OPCUA_POLICY_FILE": "your-value",
        "OPCUA_ALLOWED_TOOLS": "your-value",
        "OPCUA_ALLOWED_WRITE_NODES": "your-value",
        "OPCUA_ALLOWED_METHODS": "your-value",
        "OPCUA_ALLOW_ACKNOWLEDGE_ALARMS": "your-value",
        "OPCUA_ALLOW_INSECURE_CONTROL": "your-value",
        "OPCUA_ALLOW_UNVERIFIED_SERVER_CONTROL": "your-value",
        "OPCUA_ALLOW_OUT_OF_RANGE_WRITES": "your-value",
        "OPCUA_AUDIT_FILE": "your-value",
        "OPCUA_AUDIT_FSYNC": "your-value",
        "OPCUA_AUDIT_CHAIN": "your-value",
        "OPCUA_AUDIT_CHAIN_KEY_FILE": "your-value",
        "OPCUA_OPERATOR_ID": "your-value",
        "OPCUA_RECONNECT_INITIAL_DELAY_MS": "your-value",
        "OPCUA_RECONNECT_MAX_DELAY_MS": "your-value",
        "OPCUA_RECONNECT_MAX_RETRY": "your-value",
        "OPCUA_SESSION_TIMEOUT_MS": "your-value"
      }
    }
  }
}

{
  "servers": {
    "opcua": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "opcua-mcp-server"
      ],
      "env": {
        "OPCUA_SERVER_URL": "your-value",
        "OPCUA_PYTHON_BACKEND": "your-value",
        "OPCUA_SECURITY_POLICY": "your-value",
        "OPCUA_SECURITY_MODE": "your-value",
        "OPCUA_CLIENT_CERT": "your-value",
        "OPCUA_CLIENT_KEY": "your-value",
        "OPCUA_APPLICATION_URI": "your-value",
        "OPCUA_SERVER_CERT": "your-value",
        "OPCUA_SERVER_TRUST_STORE": "your-value",
        "OPCUA_SERVER_APPLICATION_URI": "your-value",
        "OPCUA_USERNAME": "your-value",
        "OPCUA_PASSWORD": "your-value",
        "OPCUA_USER_CERT": "your-value",
        "OPCUA_USER_KEY": "your-value",
        "OPCUA_PROFILE": "your-value",
        "OPCUA_POLICY_FILE": "your-value",
        "OPCUA_ALLOWED_TOOLS": "your-value",
        "OPCUA_ALLOWED_WRITE_NODES": "your-value",
        "OPCUA_ALLOWED_METHODS": "your-value",
        "OPCUA_ALLOW_ACKNOWLEDGE_ALARMS": "your-value",
        "OPCUA_ALLOW_INSECURE_CONTROL": "your-value",
        "OPCUA_ALLOW_UNVERIFIED_SERVER_CONTROL": "your-value",
        "OPCUA_ALLOW_OUT_OF_RANGE_WRITES": "your-value",
        "OPCUA_AUDIT_FILE": "your-value",
        "OPCUA_AUDIT_FSYNC": "your-value",
        "OPCUA_AUDIT_CHAIN": "your-value",
        "OPCUA_AUDIT_CHAIN_KEY_FILE": "your-value",
        "OPCUA_OPERATOR_ID": "your-value",
        "OPCUA_RECONNECT_INITIAL_DELAY_MS": "your-value",
        "OPCUA_RECONNECT_MAX_DELAY_MS": "your-value",
        "OPCUA_RECONNECT_MAX_RETRY": "your-value",
        "OPCUA_SESSION_TIMEOUT_MS": "your-value"
      }
    }
  }
}

Your choice stays on this device in a cookie; no account needed.

Values you fill in

• OPCUA_SERVER_URL required env
  URL of the OPC UA server to connect to, including any path the server expects. Read once at startup: one process serves one endpoint. Verify who answers with an exact server certificate pin or a conf…
• OPCUA_PYTHON_BACKEND env
  Select the Python client implementation. The maintained asyncua client is the default; legacy provides the one-release rollback path for uncovered vendor incompatibilities. This setting affects the P…
• OPCUA_SECURITY_POLICY env
  Encryption suite to negotiate for the secure channel. Anything other than None needs a client certificate and key. The two AES suites are Node-only: the Python runtime refuses them at startup rather…
• OPCUA_SECURITY_MODE env
  Message security mode for the secure channel. Sign authenticates messages without encrypting them. A policy with mode None, or a mode without a policy, stops the server at startup; leaving it blank n…
• OPCUA_CLIENT_CERT env
  Path to the certificate (PEM or DER) this client presents as its application identity. Required by any security policy other than None. A path that does not exist stops the server at startup.
• OPCUA_CLIENT_KEY secret env
  Path to the private key matching the client certificate. A path, never key material. Whoever can read the file can impersonate this client: keep it readable only by the account running the server. A…
• OPCUA_APPLICATION_URI env
  Application URI announced to the server. Set it only for a certificate that carries no URI of its own. A configured URI that conflicts with the certificate is refused before connecting. Leave blank f…
• OPCUA_SERVER_CERT env
  Path to the OPC UA server's own certificate (PEM or DER), pinned: a server presenting any other certificate cannot complete the handshake. Control tools (writes, method calls, alarm actions) require…
• OPCUA_SERVER_TRUST_STORE env
  Directory with trusted/certs root CAs, issuers/certs intermediate CAs, and trusted/crl plus issuers/crl signed current revocation lists. Authenticate the OPC UA peer by its validated chain and expect…
• OPCUA_SERVER_APPLICATION_URI env
  ApplicationUri of the intended OPC UA server. Must match the peer certificate URI SAN and advertised application identity. Required with OPCUA_SERVER_TRUST_STORE.
• OPCUA_USERNAME env
  OPC UA username. The session is anonymous when unset. Cannot be combined with a user certificate. Requires a password; either one alone stops the server at startup.
• OPCUA_PASSWORD secret env
  Password for the username. Without a security policy it crosses the network in clear text. Supply it through the client's secret storage, never on a command line.
• OPCUA_USER_CERT env
  Path to the certificate identifying the user, for X.509 user authentication: a different key pair from the client certificate, which secures the channel. Requires the user key and a security policy o…
• OPCUA_USER_KEY secret env
  Path to the private key for the user certificate. It signs the server's challenge and is never sent. Whoever can read the file can log in as this user: keep it readable only by the account running th…
• OPCUA_PROFILE required env
  Which tools are offered. observe reads, browses, reads history and monitors; operator adds explicitly allowlisted writes, method calls and alarm actions; full exposes every tool and is meant only for…
• OPCUA_POLICY_FILE env
  Path to a version-1 JSON policy file, the only place per-node value bounds, writable_subtrees, preconditions, the alarm scope and deny_read can be set. Every policy variable that is set overrides wha…
• OPCUA_ALLOWED_TOOLS env
  Comma-separated tool allowlist. It can only narrow the selected profile, never widen it. An unknown tool name stops the server at startup.
• OPCUA_ALLOWED_WRITE_NODES env
  Comma-separated exact node IDs the operator profile may write, as ns=2;i=5 or, stable across a server restart, nsu= ;i=5 or a browse path from the Root folder such as /Objects/Line1/Setpoint. Setting…
• OPCUA_ALLOWED_METHODS env
  Comma-separated object_node_id|method_node_id pairs the operator profile may call. Either half may be a browse path from the Root folder. Empty fails closed: operator can call nothing. An entry witho…
• OPCUA_ALLOW_ACKNOWLEDGE_ALARMS env
  Let the operator profile act on alarms: acknowledge_alarm and every act_on_alarm action.
• OPCUA_ALLOW_INSECURE_CONTROL env
  Permit control tools on an OPC UA channel with no security policy (None). Does not cover a secured channel to an unverified server; that is OPCUA_ALLOW_UNVERIFIED_SERVER_CONTROL. Fail-open override:…
• OPCUA_ALLOW_UNVERIFIED_SERVER_CONTROL env
  Permit control tools on a secured OPC UA channel whose server is not authenticated: neither pinned with OPCUA_SERVER_CERT nor validated by OPCUA_SERVER_TRUST_STORE. Does not cover a channel with no s…
• OPCUA_ALLOW_OUT_OF_RANGE_WRITES env
  Allow a write outside the EURange the OPC UA server itself published for the node. A published InstrumentRange still applies. Fail-open override: it discards the only value bound a deployment with no…
• OPCUA_AUDIT_FILE env
  Path to an append-only file for the control audit trail, one JSON object per line, written beside stderr. Created owner-only (0600) if it does not exist; reopened when rotated away. A file that canno…
• OPCUA_AUDIT_FSYNC env
  When an audit-file record counts as written. always fsyncs each record before the control call proceeds, so it survives a power loss; none leaves it to the operating system, so it survives only a cra…
• OPCUA_AUDIT_CHAIN env
  Adds seq, prev_hash and hash to every audit record so edits, deletions and reordering can be detected with --verify-audit. sha256 catches accidental or naive edits; hmac-sha256 also resists anyone wi…
• OPCUA_AUDIT_CHAIN_KEY_FILE secret env
  Path to the HMAC key for the hmac-sha256 audit chain: at least 32 bytes, for example from openssl rand -hex 32. Surrounding whitespace is ignored. Whoever can read the key can forge the chain: a key…
• OPCUA_OPERATOR_ID env
  Label stamped on every audit record as operator_label, so a shipped log says which deployment a control call came from. Configured, never verified: it is not an identity, and mcp_principal stays null.
• OPCUA_RECONNECT_INITIAL_DELAY_MS env
  Wait before the first attempt to repair a dropped or refused connection, in milliseconds. It doubles with each further attempt.
• OPCUA_RECONNECT_MAX_DELAY_MS env
  Ceiling for the doubling retry delay, in milliseconds.
• OPCUA_RECONNECT_MAX_RETRY env
  Retries after the first attempt, per connection round, before a tool call gives up: a whole number from -1 to 1000. 0 never retries; -1 never stops trying, in bounded rounds of four retries so no sin…
• OPCUA_SESSION_TIMEOUT_MS env
  Session lifetime asked of the OPC UA server, in milliseconds. It also sets the keep-alive period, so it decides how quickly an idle connection notices the server has gone.

These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.

What it can do

Runs on your computer; the tool list appears in your AI app after you install it.

Basic checksi

We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 7, 2026

• ! Caution

  Maker matches the repo

  The publisher (midhunxavier) is not the repo owner (IndustriAgents); someone else may have listed it

• … Not checked yet

  Still maintained

  We have not read this repo from GitHub yet

• … Not checked yet

  Has a licence

  We have not read this repo from GitHub yet

• – Not applicable

  Endpoint responds

  This one runs on your computer; there is no internet endpoint

• – Not applicable

  Sign-in with OAuth

  Runs on your computer and uses local settings instead

• … Not checked yet

  No hidden instructions in tool descriptions

  Runs on your computer; we can only read tool lists from internet endpoints

Compared with others in Otheri

• More stars than 0% of the other 18348 servers in this category
• Published to the registry more recently than 95% of the other 18348 servers in this category
• Basic checks equal to or better than 24% of the other 18348 servers in this category

Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.

Alternatives

Servers in the same category from other makers, sorted by stars.

Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi

README from the maker

flowchart LR

# Node

git clone https://github.com/IndustriAgents/OPCUA-MCP.git

npm install -g opcua-mcp-server      # or: uv tool install opcua-mcp-server

claude mcp add opcua -e OPCUA_SERVER_URL=opc.tcp://localhost:4840/freeopcua/server/ -- npx -y opcua-mcp-server

codex mcp add opcua --env OPCUA_SERVER_URL=opc.tcp://localhost:4840/freeopcua/server/ -- npx -y opcua-mcp-server

[mcp_servers.opcua]

{

{

{