Prerequisites
- Your repository checked out in Devin.
- A Momentic API key in Devin’s
secret environment as
MOMENTIC_API_KEY, or an existing CLI sign-in Devin can use.
Setup with coding agent
Copy this prompt into Devin. It follows the platform quickstart and adds the Devin-specific MCP settings:Copy the setup prompt
Copy the setup prompt
Copy for coding agents
Set up with the wizard
For direct CLI setup, use a supported Node.js version and the Momentic credentials above. The project needs apackage.json; run npm init -y if it
has none. Run the wizard from that directory:
--platform ios or --platform android for mobile. For a new project, the
wizard installs the matching CLI (momentic for web, momentic-mobile for
mobile), creates the config and sample test, and runs the sample. The
--editor-tools devin option installs the skills and writes Devin’s MCP config
to .devin/mcp_config.json without relying on agent detection.
Add MCP to an existing setup
If Momentic is already installed and only the MCP registration is missing, run the installer from the directory containingmomentic.config.yaml:
Web
Mobile
.devin/mcp_config.json. Use
--client devin if automatic detection reports No coding agent detected.
For config scopes and manual server options, see the
MCP setup instructions.
Setup notes
These settings apply after either the wizard or the MCP installer registers the server. The copyable prompt above has Devin configure them. Append--daemon to the args of each Momentic server entry in
.devin/mcp_config.json. This preserves browser or device sessions across MCP
process reconnects. The wizard and MCP installer do not add it automatically.
See the web and
mobile MCP references.
On a VM without a display, add "--headful" and "false" as separate args
entries in each Momentic MCP server config. Both servers default to true. For
web, false makes browser sessions headless. For mobile, it skips opening the
remote-control viewer without changing the emulator UI.
The wizard and MCP installer do not add this flag automatically. The
momentic_session_start tool accepts headful to override the server default
for an individual session; the legacy headfulBrowser parameter remains an
alias. See the
web MCP browser options and
mobile MCP session options.
Check npx momentic mcp --help before changing an existing web entry. If the
installed release does not list --headful, use "--headful-browser" and
"false" instead. For MCP session overrides, use headfulBrowser if the
installed server’s tool schema does not list headful.
The wizard installs Chromium for web. Android needs adb and ANDROID_HOME or
ANDROID_SDK_ROOT, including for remote emulators; have Devin install missing
Android platform-tools. Use remote
iOS simulators on Devin’s Linux machine; local simulators require macOS. See the
iOS prerequisites.
Verify
Start a new Devin session in the configured repository. Ask it to list tools whose names start withmomentic_ and call one, such as
momentic_get_artifacts. Confirm that MOMENTIC_API_KEY is available where
Devin starts MCP if the call fails to authenticate.
For a new project, also confirm that the wizard’s sample test passed. The web
sample tests Momentic’s demo app; the iOS and Android samples create a contact
in the native Contacts app. None of these samples test your app. Continue with
the setup prompt to write and run a test for your own user flow. If MCP tools
are not available in the session, Devin can use the installed skills and CLI
instead.
Fix a failing run
When a cached locator no longer matches, Momentic tries to resolve the target again from its description. If the run still fails, Devin can read the evidence through MCP and investigate the cause.1
Run the affected tests
Ask Devin to run them from the project directory, for example
npx momentic run --labels smoke --upload-results.2
Point it at the failing step
Name the maintenance skill in the prompt:The agent reads the failing step’s before and after screenshots, the trace
with the DOM, network requests, and console output, and the run history for
the branch.
3
Let it decide where the fix belongs
A product bug goes back into the code. A stale locator or an intended
behavior change goes into the test file, in the same pull request as the
product fix.