ats-mcp

An MCP server that lets an LLM drive ActionTestScript test sessions — web, mobile, desktop, and API — through ats-core's REPL.

Use it with Claude Code, Claude Desktop, Cursor, or any MCP-capable client to have the assistant actually interact with a system under test: launch channels, click elements, capture screenshots, inspect the DOM or the mobile view hierarchy, run ATS scripts — all as tool calls.

Two distributions are available, both wired to the same set of tools:

	Install	Best for
npm	`npx -y ats-mcp` (package)	Node-friendly devs, the broader MCP community
JAR	Download `ats-mcp-X.Y.Z.jar` from Releases	Users who already have Java but no Node

How it works

MCP client (Claude Code / Desktop / …)
         │
         ▼
   ats-mcp launcher  (Node OR Java — see /node and /java in this repo)
         │
   spawns / loads
         │
         ▼
  AtsReplServer (ats-core)
         │
  ┌──────┼──────┬───────┐
  ▼      ▼      ▼       ▼
 web   mobile  desktop api

On first use, the launcher provisions everything ATS needs under ~/.actiontestscript/:

libs — downloaded from https://actiontestscript.org/releases/ats-libs/<version>.zip if ~/.actiontestscript/libs/ is missing.
system driver (for desktop-app automation) — latest version pulled from https://actiontestscript.org/releases/ats-drivers/<os>/system/, upgraded automatically when a newer one is published.
browser drivers — fetched on-demand by ats-core itself on the first start_channel per browser/version.

No manual install step — npx -y ats-mcp or java -jar ats-mcp.jar is enough to go from zero to web/desktop/api automation.

Prerequisites

Java 17+ (always required — ats-core is JVM). Install from Adoptium Temurin or your package manager.
Node 18+ (only if you use the npm distribution). Install from nodejs.org or your package manager.

No Maven required — both distributions ship pre-built. Maven is only needed to build the JAR from source (see java/).

Configure your MCP client

Claude Code

Add a .mcp.json at the project root:

{
  "mcpServers": {
    "ats": {
      "command": "npx",
      "args": ["-y", "ats-mcp@latest"]
    }
  }
}

Or, with the JAR:

{
  "mcpServers": {
    "ats": {
      "command": "java",
      "args": ["-jar", "/path/to/ats-mcp-0.4.0.jar"]
    }
  }
}

Claude Desktop

Same shape, in claude_desktop_config.json.

Environment variables

Name	Purpose	Default
`ATS_VERSION`	Version of `ats-automated-testing` to bootstrap.	`3.6.6`
`ATS_HOME`	Where ATS libs and drivers live.	`~/.actiontestscript`
`JAVA_BIN`	Path to the `java` executable.	`java` on PATH

Tools exposed

30 tools, grouped by purpose:

Session / channels

Tool	What it does
`start_channel`	Open a web / mobile / desktop / api / SAP channel
`stop_channel`	Close a channel
`switch_channel`	Make a channel active

Navigation (web)

Tool	What it does
`goto_url`	Navigate to a URL
`navigate_back`	Browser history back
`navigate_forward`	Browser history forward
`refresh`	Reload the current page

Interaction

Tool	What it does
`click`	Mouse-click on an element
`hover`	Mouse-over an element
`send_keys`	Type text into an element
`press_key`	Press a special key (ENTER, TAB, arrows, F-keys…)
`scroll`	Scroll an element by a signed pixel offset
`drag` / `drop`	Two-step drag-and-drop on source → target
`select_option`	Select a `<select>` option by text/value/index
`file_upload`	Upload a local file to a file-input
`handle_dialog`	Accept/dismiss/default a JS alert/confirm/prompt

Inspection

Tool	What it does
`screenshot`	Capture a PNG of the current state
`capture_tree`	Dump the DOM / view hierarchy
`find_elements`	Enumerate elements matching a CSS selector (web) or SAP tag
`evaluate_js`	Run JavaScript in the page and return its value
`console_logs`	JS console messages captured on the active web channel
`network_list`	HTTP requests captured (with index for `network_detail`)
`network_detail`	Full request/response for one exchange
`network_cookies`	Cookies on the active web channel

Window / tabs

Tool	What it does
`window_resize`	Resize (and optionally move) the window
`window_switch`	Switch tabs by index / name / URL substring
`window_new_tab`	Open a new tab, optionally at a URL
`window_close`	Close the current tab/window

Escape hatch

Tool	What it does
`run_ats_block`	Execute a sequence of raw ATS action lines

Positioning vs Playwright MCP

ats-mcp covers the same interaction surface as @playwright/mcp for the web, plus three things Playwright doesn't do:

Multi-platform — web, mobile (Android/iOS physical, simulators, emulators, Genymotion Cloud), desktop apps (via the ATS system driver), REST/SOAP APIs, and SAP GUI.
Implicit wait built-in — element lookups retry with backoff, so the LLM doesn't need to stitch wait_for calls around every action.
Raw escape hatch — run_ats_block exposes the full ATS action vocabulary when a purpose-built tool isn't enough.

Repo layout

ats-mcp/
├── node/      — TypeScript implementation (published to npm)
├── java/      — Maven implementation (released as a fat JAR)
├── README.md
└── .gitlab-ci.yml

Both implementations target the same protocol surface and share the same tool definitions.

License

Apache-2.0 — same as ats-core.

ats-mcp

ats-mcp

How it works

Prerequisites

Configure your MCP client

Claude Code

Claude Desktop

Environment variables

Tools exposed

Positioning vs Playwright MCP

Repo layout

License

Reviews