TiaCommander — MCP Server for Siemens TIA Portal

Version	3.42.0
Protocol	MCP 2024-11-05 (stdio)
Runtime	.NET Framework 4.8
TIA Portal	V17 – V20 (Openness API, tested on V19)
License	Proprietary (free beta)

New in this release: a new technology_objects tool — 15 actions for listing and reading technology objects, changing parameters, structural edits, export/import, and connecting an object to its hardware; per-project PLC credentials with a new Credentials tab in the Manager — a project's own password is tried first, a global one is the fallback; transactional block overwrites — the block is exported before the import and restored if the import fails, and overwrites no longer lose attributes, block numbers or folder placement; and compiler results that list only real diagnostics, so totals always match the compiler's own count. Dozens more fixes and improvements since v3.15.2 — see CHANGELOG.md for the full list.

*V17 through V20 are supported for project work. V16 and older are detected and refused with a clear message. Only V19 is fully tested; the others are expected to work as TIA Portal maintains backward-compatible Openness APIs across versions.

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Overview

TiaCommander is an MCP server that connects AI assistants to Siemens TIA Portal via the Openness API. It enables AI-assisted PLC programming, project management, library operations, hardware configuration, cross-reference analysis, and deployment — all through natural language.

Tested AI clients: Claude Desktop, Claude Code, VS Code (Copilot), Cursor, Windsurf, Codex CLI, Gemini CLI.

19 tools, 230 actions covering the full TIA Portal project lifecycle.

Tool	What it does
admin	Server administration, usage stats, export storage
alarm_text	Alarm texts and text lists, XLSX import / export
blocks_read	Read, inspect and export FB / FC / OB / DB blocks (XML, SCL)
blocks_write	Create and import blocks (SCL, LAD, FBD, STL)
db	Global and instance data-block members and values
diagnostics	Connection setup, online / offline compare, PLC state
download_upload	Compile-checked download to / upload from the PLC
folders	Navigate and organise the project-tree groups
get_info	Server capabilities and version
hardware	Device, rack / slot, network and I/O configuration
library	Master copies, library types, versioned instantiation
live_data	Live values and CPU diagnostics from the running controller
open_manager	Open the TiaCommander Manager window
session	Open, save, archive and switch projects; connection lifecycle
tag	PLC tag tables: create, edit, search, address assignment
technology_objects	Axes and other technology objects: read, tune, connect to hardware
udt	User-defined types: create, edit members, import / export
watch	Watch and force tables
xref	Cross-references: callers, unused blocks, orphaned instance DBs

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What's in the download?

TiaCommander-v3.42.0-portable/
├── bridge/                              ← Live PLC data helper (S7CommPlus / TLS)
│   ├── libcrypto-3-x64.dll
│   ├── libssl-3-x64.dll
│   ├── S7CommPlusDriver.dll
│   ├── TiaCommander.S7Bridge.exe
│   ├── TiaCommander.S7Classic.dll
│   └── zlib.net.dll
├── data/
│   └── exports/                         ← Export output folders
│       ├── alarm_text/
│       ├── hardware/
│       ├── tag/
│       └── watch/
├── docs/
│   ├── configs/
│   │   ├── claude_code.txt
│   │   ├── claude_desktop_config.json
│   │   ├── codex_cli_config.toml
│   │   ├── cursor_mcp.json
│   │   ├── gemini_cli_settings.json
│   │   ├── generic_stdio.json
│   │   ├── vscode_copilot_mcp.json
│   │   └── windsurf_mcp_config.json
│   ├── 1-QUICKSTART.md
│   ├── KNOWN_LIMITATIONS.md
│   ├── LICENSE.txt
│   ├── README.md
│   └── THIRD-PARTY.md
├── help/
│   ├── github-offline.html
│   └── readme-offline.html
├── licenses/                            ← Full third-party licence texts
│   ├── Apache-2.0.txt
│   ├── BSD-3-Clause.txt
│   ├── GPL-3.0.txt
│   ├── LGPL-3.0.txt
│   ├── Microsoft-WebView2-SDK.txt
│   ├── MIT.txt
│   └── Polyform-Noncommercial-1.0.0.txt
├── Resources/
│   ├── logoBlack.png
│   └── tiacommander.png
├── runtimes/                            ← WebView2 native loaders
│   ├── win-x64/native/WebView2Loader.dll
│   ├── win-x86/native/WebView2Loader.dll
│   └── win-arm64/native/WebView2Loader.dll
├── Templates/                           ← Block XML, alarm & diagnostics templates
│   ├── diagnostics/
│   │   ├── TC_Diag_1200.xml
│   │   └── TC_DiagOB.xml
│   ├── Fb.xml
│   ├── Fc.xml
│   ├── GlobalDb.xml
│   ├── Ob.xml
│   ├── Ob_FBD.xml
│   ├── Ob_LAD.xml
│   ├── Ob_SCL.xml
│   └── TextListTemplate.xlsx
├── x64/                                 ← SQLite native library (64-bit)
│   └── SQLite.Interop.dll
├── x86/                                 ← SQLite native library (32-bit)
│   └── SQLite.Interop.dll
├── CHANGELOG.md
├── EPPlus.dll
├── EPPlus.Interfaces.dll
├── icon.png
├── manifest.json
├── Microsoft.Bcl.AsyncInterfaces.dll
├── Microsoft.IO.RecyclableMemoryStream.dll
├── Microsoft.Web.WebView2.Core.dll
├── Microsoft.Web.WebView2.WinForms.dll
├── System.Buffers.dll
├── System.ComponentModel.Annotations.dll
├── System.Data.SQLite.dll
├── System.IO.Pipelines.dll
├── System.Memory.dll
├── System.Numerics.Vectors.dll
├── System.Runtime.CompilerServices.Unsafe.dll
├── System.Security.Cryptography.Xml.dll
├── System.Text.Encodings.Web.dll
├── System.Text.Json.dll
├── System.Threading.Tasks.Extensions.dll
├── THIRD-PARTY-NOTICES.md
├── TiaCommander.exe                     ← MCP server + Manager GUI
└── TiaCommander.exe.config

No installer, no registry changes, no system modifications. Extract, configure, and run. Download the latest .zip from GitHub Releases.

Claude Desktop users: Download the .mcpb bundle from Releases and install via Settings → Extensions → Advanced Settings → Install Extension. No config file editing needed. See the Quick Start Guide for details.

Prerequisite: Siemens TIA Portal V17 or later must be installed on your machine with the Openness component enabled. TiaCommander loads Siemens Openness libraries directly from your TIA Portal installation at runtime. Without TIA Portal, the server starts in degraded mode with limited functionality and guides you through setup.

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Why this tool exists?

First things first — we are software developers and automation engineers who use Siemens products daily — in our own facilities, at client sites, and in every project that needs industrial automation. We love it. With Siemens, it's simple — it just works. Every time. All the time.

During years of hands-on programming, wiring, testing, debugging and making things happen with Siemens PLCs, we have built TiaCommander just for our own internal needs. That's the honest reason why it exists — we built it for ourselves, and we find it awesome. It speeds things up tenfold, sometimes twentyfold, and sometimes more — until you ask yourself: how the hell were we getting things done before?!

You can get full project context through your AI assistant in under a minute. Create any block in seconds — SCL, LAD, FBD, DB — get interface structures, build multi-instance DBs, run cross-references, compile, debug, retrieve errors, and a lot more.

Every tool you see in the tool map below is built from what we actually need or use in our daily operations with Siemens PLCs. Whether you're working with S7-1200 or S7-1500 series — it doesn't matter. If Siemens TIA Portal supports it, you can use TiaCommander to manage it.

Now that we're making this tool public — we're genuinely keen on what features you're missing for your development workflow. Don't be shy — submit a feature request, file a bug report, or just tell us what you think. As an Engineer to Engineer — we read every line of feedback.

Enjoy TiaCommander.

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Architecture

AI Clients
  Claude Desktop / Code · Cursor · VS Code / Copilot · Windsurf · Codex CLI · Gemini CLI
    │
    │  JSON-RPC 2.0 · stdio
    ▼
TiaCommander MCP Server
  19 tools · 230 actions · standalone I/O · .NET Framework 4.8
    │
    │  Siemens Openness API
    ▼
TIA Portal  (V17 – V20*, tested on V19)
    │
    ▼
S7-1200 · S7-1500 · S7-300 · S7-400 · ET 200

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Tool Map

Tool / Action	#	Description
admin	13	Server administration
clear_exports		(optional olderThanHours=24) Delete expired exports.
delete_export		(exportId) Delete a single export.
get_device_profiles		All unique devices seen by the server.
get_export		(exportId; optional offset, length, raw=false) Retrieve export content with paging. raw=true returns content only, no metadata header.
get_recent_errors		(optional count=10) Last N failed tool calls with device/firmware context.
get_system_info		OS, .NET version, TIA Portal version, process uptime.
get_stats		(optional top_n=20) Call statistics per tool+action, sorted by total calls.
get_version		Server version, DB path, DB size.
list_exports		(optional tool, limit=20) Recent export results stored in export DB.
open_file		(filePath) Open a file using the Windows default application (Excel for .xlsx, browser for .html, etc.). Use after any export action to let the user inspect results immediately.
reset_device_catalog		Clear local device catalog and re-dump from TIA Portal if connected.
save_export		(exportId, outputPath) Save export content to a file. Auto-decodes base64 for binary formats (XLSX). After saving, ask the user if they want to open the file (use admin action=open_file).
search_device_catalog		(optional filter, limit=50) Search installed TIA hardware catalog from local DB. No TIA Portal needed. Use for hardware reference lookups (order numbers, CPU models, compatible modules).
alarm_text	15	Alarm texts & text lists
add_entries		(deviceName, textlistName, entries[]) Add entries to a text list. Each entry: {from, to, text}.
create_textlist		(deviceName, textlistName; optional listRange=Decimal, comment, entries[]) Create new text list. Works on empty devices (auto-seeds via template). Optionally populate with entries in one call.
delete_entries		(deviceName, textlistName, fromValues[]) Delete entries by From value.
delete_textlist		(deviceName, textlistName) Delete a user text list. System text lists rejected.
export_alarm_classes		(deviceName, outputPath) Export alarm class definitions. After export, ask the user if they want to open the file (use admin action=open_file).
export_alarm_data		(deviceName, format:csv|xlsx; optional scope:alarm_texts|textlists|alarm_classes, outputPath, includeInfoText) Export alarm data to CSV or XLSX for documentation. Defaults to exports_root\alarm_text. After export, ask the user if they want to open the file (use admin action=open_file).
export_alarm_texts		(deviceName, outputPath; optional includeInfoText) Export alarm instance texts to XLSX. After export, ask the user if they want to open the file (use admin action=open_file).
export_textlists		(deviceName, outputPath; optional textListNames[]) Export text lists to XLSX. All if no filter. After export, ask the user if they want to open the file (use admin action=open_file).
get_entries		(deviceName, textlistName) Read all entries for a text list.
import_alarm_classes		(deviceName, filePath) Import alarm class definitions.
import_alarm_texts		(deviceName, filePath) Import alarm instance texts from XLSX.
import_textlists		(deviceName, filePath; optional overwrite) Import text lists from XLSX.
list_textlists		(deviceName) List system and user text lists with name, ID, range.
update_entries		(deviceName, textlistName, entries[]) Update entries by From value. Each entry: {from, to?, text?}.
update_textlist_comment		(deviceName, textlistName, newComment) Update text list comment directly.
blocks_read	17	Read & export blocks
check_consistency		(deviceName) M10: IsConsistent flag can lag compile — use compile_all output instead.
compile_all		(deviceName) Compile all. Run early to resolve F6. Slow first run (~30-60s).
compile_block		(deviceName, blockName) Compile one block.
export_all_xml		(deviceName, outputDirectory) All blocks as .xml files. M5: arg is 'outputDirectory' not 'outputPath'. After export, ask the user if they want to open the output directory (use admin action=open_file).
export_source		(deviceName, blockName; optional outputPath, returnInline, outputDirectory) SCL/STL source. With outputPath it goes to disk (M3: it must be a DIRECTORY); omit it and returnInline applies. LAD/FBD return empty. After export, ask the user if they want to open the file (use admin action=open_file).
export_xml_file		(deviceName, blockName; optional outputPath, returnInline, outputDirectory) Block XML. With outputPath it goes to disk; omit it and returnInline applies. After export, ask the user if they want to open the file (use admin action=open_file).
export_xml_inline		(deviceName, blockName) Parsed XML summary. F6 applies.
get_all_interfaces_summary		(deviceName) Member counts per section for all blocks.
get_compiler_errors		(deviceName) Error-only filter. Same M8 recompile quirk.
get_compiler_messages		(deviceName) M8: triggers fresh compile. Prefer compile_all output if just compiled.
get_details		(deviceName, blockName) Type, number, language, interface size, consistency.
get_edit_capabilities		(deviceName, blockName; optional networkIndex) #232 P0: THE DISCOVERY CALL. Per network: its OWN compile-unit language (the block-level one is misleading on mixed-language blocks), whether the rung model round-trips it, which write actions apply, and the fallback route when none do. One call instead of a dozen scattered hints. Costs ONE export - measured: there is no object-model per-network re...
get_element_pins		(deviceName, blockName, networkIndex; optional elementUId or elementIndex) The 'look before you wire' card: for a Call or instruction Part, every pin with section, EXPECTED data type (read live from the callee interface / instance structure) and current wiring (operand + its resolved type, or UNWIRED OpenCon). Without a selector: lists the network's elements with UIds. Use BEFORE blocks_write u...
get_interface		(deviceName, blockName) Full interface sections. F6: flakes on inconsistent blocks — compile_all first.
get_network		(deviceName, blockName, networkIndex; optional includeUIds) #171 rung editor READ side: reconstructs the network's flat Parts+Wires graph into a JSON rung model - EXACTLY the vocabulary create_block networks[].rungs accepts (contacts/parallelBranches/box/output/call, plus enFrom for ENO-cascaded call chains). Output: {title, comment, editable, rungs[], unmodelled[]}. editable=true means the mod...
get_xml_raw		(deviceName, blockName) Raw XML string. F6 applies.
list		(deviceName; optional typeFilter:all|code|OB|FB|FC|DB|GlobalDB|InstanceDB, includeInstanceDbs) Compact block table.
blocks_write	26	Create & import blocks
add_interface_member		(deviceName, blockName, section, memberName, dataType; optional startValue, comment, confirm) #171 interface editor: add a member to an FB/FC/OB interface section (Input, Output, InOut, Static, Temp, Constant). BLAST RADIUS is computed FIRST (xref callers whose call sites go out of date + the FB's instance DBs + the #183 reinitializeDataBlocks warning: download resets actual values of affected ...
add_multi_instance_member		(deviceName, parentFB, memberName, innerType; optional onCollision=fail|replace) Add typed static member to FB. innerType must exist in device or project.ProjectLibrary.
add_network		(deviceName, blockName; optional position, title, comment) Insert empty network at position (default: end). LAD/FBD only — SCL blocks have a single compilation unit and do not support multiple networks. Use populate_network / insert_rung to add logic afterward.
copy_block		(deviceName, blockName, newName; optional targetFolder, createParents=false) Duplicate a block under a new name (block names are PLC-WIDE unique, so newName is mandatory and checked recursively). targetFolder omitted = copy lands next to the source block. The copy gets the next free number of its type. Source block is never modified. OFFLINE required.
create_block		(deviceName, blockName, blockType:FB|FC|OB, language; optional blockNumber, interface, sclCode, networks, blockTitle, blockComment, author, version, memoryLayout, secondaryType, overwrite, targetFolder, createParents) Full block creation with custom interface and logic. blockNumber auto-assigned if omitted — ONLY for genuinely new blocks. When using overwrite=true to update an existing block (e...
create_fb		(deviceName, fbName; optional fbNumber, language:LAD|SCL|FBD (STL not supported - Openness limitation), author, version, autoCompile=true, targetFolder, createParents=false) New FB. Number auto-assigned if omitted. Auto-compiles and returns errors. targetFolder ('Motors/Drives' syntax) creates the block directly inside that folder; missing folders are an ERROR unless createParents=true.
create_fc		(deviceName, fcName; optional fcNumber, language, returnType=Void, author, version, autoCompile=true, targetFolder, createParents=false) New FC. Number auto-assigned if omitted. Auto-compiles and returns errors. targetFolder as in create_fb.
create_ob		(deviceName, obName; optional obNumber, language, author, version, autoCompile=true, targetFolder, createParents=false) New OB. Number auto-assigned if omitted (starts at 123). obNumber=1 allowed; 2-122 reserved. Auto-compiles and returns errors. targetFolder as in create_fb.
delete_block		(deviceName, blockName; optional force=false) Delete any block. Instance DBs rejected unless force=true (useful for orphaned instance DBs).
delete_interface_member		(deviceName, blockName, memberName; optional section, confirm) Remove an interface member. Same blast-radius confirm gate. Logic still referencing the member will fail compile - check first with xref get_references.
delete_network		(deviceName, blockName, networkIndex) Remove network by 0-based index. Refuses if last network. LAD/FBD only.
delete_rung		(deviceName, blockName, networkIndex, rungIndex; optional expectTitle) Remove rung rungIndex. Refuses when the NEXT rung chains (enFrom) from the deleted one - retarget or delete the tail first.
delete_scl_statement		(deviceName, blockName, networkIndex, statementIndex, matchText) #232 P0: remove ONE statement from an SCL network, in one call. Read the statements first with blocks_read action=get_network, which lists them 0-based with whitespace-normalised text. matchText is MANDATORY and is compared against the statement AT statementIndex before anything is modified - indexes shift under every edit, so an ...
import_xml_file		(deviceName, filePath; optional overwrite, autoCompile=true, targetFolder, createParents=false) Import from XML file. Auto-compiles and returns errors. Preferred for large payloads. targetFolder as in import_xml_inline. OVERWRITE IS A WHOLE-OBJECT REPLACE, NOT A MERGE: with overwrite=true, any element ABSENT from your document is RESET to its default rather than preserved (ImportOptions.Overrid...
import_xml_inline		(deviceName, xmlContent; optional overwrite, autoCompile=true, targetFolder, createParents=false) Import block from XML string. Auto-compiles and returns errors. Large payloads (12KB+) verified. targetFolder imports into that folder; without it, overwrite=true auto-targets the folder the existing block already lives in (owning-group import). OVERWRITE IS A WHOLE-OBJECT REPLACE, NOT A MERGE: wit...
insert_rung		(deviceName, blockName, networkIndex, rung; optional position, expectTitle) #171 rung editor: insert ONE rung (create_block rung vocabulary: contacts/parallelBranches/box/output OR call{blockName,blockType,instanceDB,scope,pins}, optional enFrom for eno chaining) into an EXISTING LAD network at position (default: append). The network must be fully modelled (get_network editable=true) - refused ...
move_block		(deviceName, blockName, targetFolder; optional createParents=false) Move a block into another folder ('' or '/' = container root). Openness V19 has NO native move — this is export -> delete -> import into the target group, with automatic restore to the original folder if the import fails. Verified by re-resolution and recompiled afterwards. OFFLINE required.
populate_network		(deviceName, blockName, networkIndex, rungs; optional overwriteExisting, expectTitle) Fill a network with a rungs[] array (create_block networks[].rungs vocabulary incl. enFrom chains). Empty networks (fresh add_network) populate directly; non-empty networks require overwriteExisting=true AND full modelling (get_network first to preserve content). #164-style pre-import validation with JSON-path...
remove_multi_instance_member		(deviceName, parentFB, memberName) Remove static multi-instance member.
rename_block		(deviceName, blockName; optional newName, newNumber) Rename/renumber. Does NOT auto-cascade to callers.
replace_network		(deviceName, blockName, networkIndex; optional title, comment) Replace network title/comment. LAD/FBD only — sclCode not supported (SCL XML is tokenized; use create_block with overwrite=true to rebuild SCL blocks).
split_network		(deviceName, blockName, networkIndex, splitBefore[], titles[]) #232 P0: cut ONE SCL network into several at statement boundaries, each with its own title. splitBefore lists the statement i