Why Mo, not your coding agent's computer use

Your coding agent can already drive your app. Devin computer use gives it a full desktop, and Codex drives a browser with its Computer Use plugin. Each one checks one flow at a time. Mo is built for the other job: many flows at once, across a whole product.

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Speed and parallelism

A coding agent with computer use has one session and one screen, so it checks one flow, then the next, and your terminal waits for each one. Ten flows cost ten times one flow. A Mo session gives every test case its own agent and its own browser, simulator, or emulator, and runs them on our infrastructure. A session runs a hundred or more at once, up to your plan limit, so a pass over dozens of flows does not take the sum of their run times. One customer session ran 116 agents, returned 27 bugs from one bug bash, and covered two days of manual QA in one run. Cases and bugs appear in the report while the session continues, and the first bugs can appear within minutes, so you read findings before the pass ends. Your terminal stays free the whole time. See parallel agents and during the session.

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Agents with one job each

Your coding agent is one general agent with computer use. It plans, explores, decides, and writes up the result in one conversation, so the agent that found a bug is also the agent that decides it is a bug. A Mo session splits that work into roles. A session agent plans the coverage and dispatches. Explore agents map one product area and record test cases. Bug bash agents each take one case and work it in their own browser. A bug reproducer takes one suspected bug and confirms it from a clean start. Each role runs with its own tools and its own browser. See the agents in a session.

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Teams build this in-house

The setup is a coding agent plus Playwright MCP: one command for a bug bash, and a scheduled run that explores the product and posts a report. It works. The problem is that the agent plans a new trajectory on every run, so two runs of the same brief return different coverage and a different report. And the browser tooling covers web only, so mobile stays manual. A Mo session keeps the shape fixed, and the agents run on our infrastructure instead of your machine. The report has the same fields every run, a case carries a verdict you can read next to last week’s, and the same session can target web, iOS, and Android. See targets.

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Built on the same steps as a Momentic test

Devin’s desktop and Codex’s browser run the same loop: screenshot, act, screenshot again, and the verdict is whatever the last screenshot showed. Codex also asks before it acts on a site you have not allowed, so an unattended pass can stop and wait for you. Mo’s agents drive the browser with Momentic steps, the same step format the CLI runs, and they can read the accessibility tree when a screenshot does not show which element to act on. A case comes back as fields you can read: preconditions, an outline, and acceptance criteria. When the sandbox cannot reach something the case needs, the report records a gap instead of a bug. See session reports.

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Start it from the web app or your terminal

You start a session in the web app, or with the mo CLI from your terminal. The CLI matters because it is what a coding agent can run. The mo-qa skill lets Claude Code, Cursor, Codex, or Devin start the session and follow it for you, so your coding agent keeps working on the change it made while Mo covers the rest of the product. See the Mo CLI and install Mo skills.

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Cover the flows you did not change

A coding agent tests what it changed, because that is the context it holds. It does not know which other flows the change can break. Mo starts from a product objective, an uploaded spec, or an open prompt, and the explore agents walk the product area to find the cases, including states that no test covers. You get the case list in the report, so you can see what was covered and add what was missed. See session reports and use cases.

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What reaches the report

An agent that sees a failure once can report only what it saw once, and you are left deciding whether to trust it. In Mo, a suspected bug goes to a bug reproducer agent that starts from a clean session with no state from the agent that found it. Only a bug it reproduces reaches you. Mo reports a case that access blocks as blocked instead of as a bug. See session reports.

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What you keep after the run

A coding agent leaves you a conversation. Close it, and the reasoning behind the verdict is gone with it. A Mo session leaves a report: every case with a verdict, and every bug with expected behavior, actual behavior, reproduction steps, and a recording. A case syncs to TestRail, Qase, or Testiny. An accepted bug files to Jira or Linear with a link back to the session. A run on a pull request reports a status check you can require before a merge. See session reports and integrations.

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What Mo remembers about your product

A coding agent session starts with no memory of your product, so you explain the same conventions on the next pass. Momentic keeps a knowledge base of your terminology, your rules, and your known flows, and the agents retrieve it during a session. Triage adds to it, so a later run does not report the same intended behavior again. See triage.

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When to use your coding agent instead

Use your coding agent when one flow is the whole job and it changed the code, because it can check that flow in the same conversation. Start a Mo session for the rest: a pass over a product area, a run on a pull request that reports a status check, and a bug confirmed by an agent that did not find it.

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