For plants and utilities running Ignition 8.3

Ignition MCP without the full-access key: a read-only tool list for Claude

Ignition MCP today means Inductive Automation's MCP Module, in early access since 13 February 2026, which ships no pre-built tools. Ignition's own documentation warns that gateway API keys can modify configuration, tags and projects. Pexon defines a read-only tool list over tag values, history and the alarm journal, with every call logged to the person asking.

The correction

The Ignition MCP Module is a toolkit, not a connector. It publishes whatever tools your project defines, so whether the result is safe is decided in your Designer, not by Inductive Automation.

Checked on 19 September 2026

Three ways to put Ignition behind MCP, and what each leaves open

Route	What you get	What it leaves open
Official MCP Module, early access	A gateway module where each project defines its own tools, resources and prompts. Early access since 13 February 2026, requiring Ignition 8.3.5, authenticated with an API key in the X-Ignition-API-Token header.	No GA date. No pre-built tools. Tools must live in a standalone, non-inheritable project, per the module's forum thread.
Community servers	ignition-mcp on PyPI, and Caldera with more than 110 tools including Perspective and HMI development.	Early, hobby-level maturity. Development tools of that kind belong on a development gateway only.
Your own server on the Gateway API	Ignition 8.3's REST routes, described by an OpenAPI spec the gateway serves at /openapi, with configuration resources under /data/api/v1/resources.	The API is built for configuration as code. Reading plant data through it means working around what it was designed to change.

Why Ignition is hard for an agent

Four things that decide the tool list before any tool is written

API keys are wide. Ignition's 8.3 documentation cautions that API keys grant full access to the gateway's HTTP API routes, including the ability to modify configuration, tags and projects. Security levels apply, but a key is not a read-only credential by construction.
Tools are arbitrary scripts. The module runs what a project defines. A tool that calls a tag write is as easy to add as one that reads, so the list itself is the security boundary and needs an owner who signs it.
Naming is per project. Tag providers, folder structures and UDT definitions differ from one integrator's project to the next. The agent needs a written map of yours, not a guess from tag paths.
The gateway bridges OT and IT. Many gateways talk to PLCs on one side and to databases and browsers on the other. Where the MCP endpoint is exposed decides which zone an agent is effectively standing in.

The first tool list

Five read tools, each wrapping one documented 8.3 function

Defined in a standalone project on the gateway. Each tool calls exactly one scripting function and returns a bounded result; nothing else is registered.

# First Ignition MCP tool list: read-only, one standalone project
# Each tool wraps one documented Ignition 8.3 scripting function.
browse_tags(folder_path)                   # system.tag.browse
read_tags(tag_paths)                       # system.tag.readBlocking, capped paths per call
tag_history(paths, start, end, aggregate)  # system.historian.queryAggregatedPoints
active_alarms(source_filter, min_priority) # system.alarm.queryStatus
alarm_journal(start, end, source_filter)   # system.alarm.queryJournal

# Not registered: system.tag.writeBlocking, tag and UDT configuration edits,
# project resources, Perspective view generation, /data/api/v1/resources.

Reviewers read the last two lines first. If anything in them appears in the project, the connector is not the one on this page.

What changes on the plant

A shift lead asks why a line stopped overnight and gets the tag history and the alarm journal for that window, from the same gateway operators already use.
An alarm flood is summarised by area and priority for handover, while acknowledgement stays with the operator on the HMI.
The security review is about five named read operations and one gateway endpoint, not about a key that can edit projects.
Each tool call is logged with the person who asked, the tag paths and the time window.
Engie's use of Ignition across 18 hydroelectric plants in Spain, documented by Inductive Automation, is the multi-site shape where one tool list serves every site that shares a tag structure.

Start with the Readiness Blueprint.

Two weeks, €4,900 fixed price. We map your tag providers and UDTs, agree the read-only tool list with the owner of the gateway, settle where the MCP endpoint sits and how its access is scoped, and hand back a costed build plan. What we need: access to a development or test gateway on 8.3, one engineer who knows the project, and one question the agent should answer. All prices are net and exclude VAT.

We have not built an Ignition connector for a named customer yet. What is written here is the method and the specific constraints of Ignition, not a track record.

Sources: Ignition MCP Module early access thread · Inductive Automation, MCP Module announcement · Ignition modules page · Ignition 8.3 API keys · Ignition 8.3 Gateway OpenAPI · system.historian.queryAggregatedPoints · system.alarm.queryJournal · ignition-mcp on PyPI · Caldera on PulseMCP · Engie case study. Read 19 September 2026. Vendor documentation changes; verify against the current release.

MCP servers for industrial systems: 52 systems mapped — where Ignition sits among the SCADA and historian systems
OPC UA MCP server and Sparkplug B UNS — the protocol route when the data should not go through the gateway
PI System integration for Claude — the historian route for sites that archive in PI
Industrial MCP server security — why vendor OT servers are deployed read-only, with five cases

Questions Ignition owners ask about MCP

Is the Ignition MCP Module generally available?

Not as of 19 September 2026. Inductive Automation announced the module on 17 September 2025 with a release planned for 2026 in its Enterprise Integration Solution Suite. Early access opened on 13 February 2026, requiring Ignition 8.3.5, and the forum thread's latest update we found is from 24 April 2026 with no GA date. The public modules page did not list it when we checked.

Should we wait for the MCP Module or build a server now?

Build the tool list now, on the module if you can run early access. The module deliberately ships no tools, resources or prompts, so the work that decides whether it is safe, which operations exist and under whose identity, is yours either way. A tool list written against Ignition's documented scripting functions moves to the GA module unchanged; only the packaging would differ.

Can Claude write tags or change the project through Ignition MCP?

It can if someone defines such a tool, and we do not. Writing a tag on a running gateway can reach a PLC, and editing a project changes what operators see. Our first tool list reads tag values, tag history, active alarms and the alarm journal. Designer help, such as generating Perspective views, belongs on a development gateway with its own key, never on production.

What does an Ignition MCP connector cost?

The two-week Readiness Blueprint is fixed at €4,900: the tag providers and UDTs mapped, the read-only tool list agreed, the gateway placement and key scope settled, and a costed plan. A first production connector is usually a use-case pilot from €15,000. All prices are net and exclude VAT.

What will an Ignition MCP connector not solve?

It will not make a messy tag tree readable by itself. If UDTs and tag paths differ project by project, the agent needs a mapping we write with your engineers, and where history is not enabled on a tag there is no history to query. It is also not an operator: it can summarise an alarm flood for a shift lead, not decide which alarm to act on.

Next step

Not a sales call. An architecture call.

Thirty minutes with the engineer who would define the tools, with your tag provider structure on screen if you can share it.