Mushi Mushi

Your AI built it. Mushi Mushi makes it better.

Mushi Mushi checks your live site, shows where people get stuck, and reviews your code. Your users can tap a button to report a bug. Each problem comes with a plain-English explanation and a fix that Lovable, Cursor or Claude Code can apply.

Fix what breaks · Smooth the journeys people take · Clean up the code — one place, from your editor.

Check your live app free → No sign-up, nothing to install.

Add it to Lovable or Bolt with one prompt → No terminal, about five minutes, free for one app.

Or, in your app's folder:

npx mushi-mushi

_{Built for the vibe coder who ships fast with Cursor, Claude Code, Lovable or Bolt.}

Quick start · How it works · Docs · Sample diagnosis · Why not Sentry? · Self-host · Vision

_{↑ What comes back when a user writes "Checkout button does nothing on my phone". Click for the whole sample, from their words to the fix prompt, without signing up.}

How it works

_{↑ Short videos that show every click: a user reporting a bug, the diagnosis, connecting your editor, and the fix shipping. Watch them on How it works.}

flowchart LR
    U["Your users<br/>tap the bug widget"] --> M
    S["Your monitoring<br/>Sentry, Crashlytics… (optional)"] -.-> M
    M["Mushi Mushi<br/>one queue · diagnosis · fix"] --> E["Your editor or agent<br/>Cursor, Claude Code (MCP)"]
    E --> P["Draft PR<br/>you review it"]
    P --> R["Release<br/>report closes, user is told"]

1. Capture. A user taps the widget. Mushi Mushi records a screenshot, the route, their note, and the last console and network events.
2. Diagnose. Mushi Mushi writes the root cause in plain English with a fix prompt. Twenty reports of the same broken button become one row.
3. Fix. Your editor reads the diagnosis over MCP and makes the fix with its own model. If you prefer, an agent opens a draft PR that you review like any other. On hosted Mushi Mushi the built-in fixer needs no key of your own; Cursor's agents need your Cursor key; or run fixes on your own computer with the Mushi Mushi worker. With your own Anthropic or OpenAI key, a second AI (Claude Opus, or GPT on an OpenAI key) reviews each agent PR first. Mushi Mushi will not merge a PR it says to hold unless you override it in the console and give a reason.

It catches the bugs that never throw an error: the pay button hidden under the keyboard, the Save button tapped twice because nothing happened, the dashboard that takes 12 seconds.

Beyond bugs. The same queue improves the rest of the app:

• Journeys. The Journey optimizer maps how people move from page to page, from real visits, and flags dead ends, loops, pages people leave from, and orphan or duplicate pages. Each finding has a plain suggestion and a prompt your coding agent can run. The map from visits needs no key; the crawl of your live site needs a Firecrawl key. A first-time user test shows where a new user gets stuck (it runs on your own coding agent).
• Code. Known security holes in your dependencies (once GitHub is connected), code audits run by your own agent, and clean-up of the branches and PRs Mushi Mushi made. Every change is a pull request you review.

Quick start

npx mushi-mushi

Run it in your app's folder. What happens next:

1. You sign in through your browser. Your free project and key are made for you. There is nothing to copy.
2. It installs Mushi Mushi and shows you a few lines of code. Add them to your app (or ask your AI editor to). They show a small report button.
3. Your users tap the button when something is wrong and write one sentence. Mushi Mushi adds a screenshot and what the app was doing.
4. You get the cause in plain English, and a fix your AI editor can apply.

Prefer to have your AI editor run it? Paste this into Cursor or Claude Code:

Add Mushi Mushi to this app. In the project folder, run `npx mushi-mushi --yes`.
It prints a sign-in link: show it to me and wait while I approve it in my
browser. Then add the code it prints to the file it names, and tell me which
file you changed.

Starting from nothing? npx mushi-mushi --template vue my-app (or svelte, node) makes a starter app with Mushi Mushi already in it. Want your linter to catch the buttons that do nothing and the fake data AI tools leave behind? Add mushi-mushi/eslint to eslint.config.js.

Then connect your editor so it can read diagnoses: one click on the Connect page, or npx mushi-mushi setup --ide cursor (or --ide claude). Ask it: "Get the latest Mushi Mushi report and fix it."

Building in Lovable or Bolt, with no terminal? Paste one script tag through your prompt instead: Mushi Mushi in Lovable or Bolt.

The SDK needs two env vars (VITE_MUSHI_PROJECT_ID / VITE_MUSHI_API_KEY, or NEXT_PUBLIC_MUSHI_*; see examples/sdk.env.example). No Sentry, no LLM key, no monitoring stack.

Before you deploy. The wizard writes those two variables to .env.local, which never reaches your host. Add them where your site is built (Vercel: Project → Settings → Environment Variables, Production; Netlify: Project configuration → Environment variables), then redeploy. Without them the report button does not appear on the live site.

Want a real diagnosis of your own code right away? A test report is one made-up sentence, so its diagnosis is thin. Bring in a bug you already know about: npx mushi-mushi sentry import (your newest unresolved Sentry issues, once Sentry is connected under Integrations in the console) or npx mushi-mushi reports file --title "…" --description "…". Connect your GitHub repository so the diagnosis can name your files.

The hosted free plan covers one app and 100 diagnoses a month, with no card and no AI key of your own (pricing). Or you can self-host.

npm install mushi-mushi        # React Native: npm install @mushi-mushi/react-native

import { MushiProvider } from 'mushi-mushi/react';

export function App() {
  return (
    <MushiProvider config={{ projectId: 'proj_xxx', apiKey: 'mushi_xxx' }}>
      <YourApp />
    </MushiProvider>
  );
}

import { MushiPlugin } from 'mushi-mushi/vue';             // Vue 3 / Nuxt: app.use(MushiPlugin, { projectId, apiKey })
import { initMushi } from 'mushi-mushi/svelte';            // Svelte / SvelteKit: initMushi({ projectId, apiKey })
import { provideMushi } from 'mushi-mushi/angular';        // Angular 17+: providers: [provideMushi({ projectId, apiKey })]
import { MushiProvider } from '@mushi-mushi/react-native';  // React Native: its own package (native code)
import { Mushi } from 'mushi-mushi';                       // any framework: Mushi.init({ projectId, apiKey })

Already on @mushi-mushi/react, @mushi-mushi/web or another @mushi-mushi/* SDK? It keeps working and keeps getting updates. mushi-mushi ships the same code; switch when you like by changing the import path.

Who it's for

• You build apps with AI, mostly on your own. You use Lovable, Bolt, Cursor or Claude Code, your app has real users, and you didn't write most of the code by hand. When someone says "it's broken", Mushi Mushi tells you the likely cause in plain English and gives your editor a fix prompt.
• You're a developer and you own your code. You read the diffs and may already run Sentry. User reports and Sentry errors land in one list with duplicates merged, and an agent's fix gets a second AI review before it can merge.
• You run a team. Reports arrive from the app, Sentry, store reviews and Slack, and nobody sees all of them. Here they share one list, each with a diagnosis, and they can go on to Linear, Jira or GitHub Issues.

The pains each group has, and where each should start: who it's for.

What's inside

Full list and maturity: SDK reference. Architecture: how the pipeline fits together.

What else it does

Most bugs never get reported. People just leave. So beyond the reports people send, Mushi Mushi can look for bugs itself and check the fixes. Each of these is off until you switch it on, and several need your own key.

A "fix first" review can go back to the agent with its findings, at most twice per PR. That is off by default and uses your organization's Cursor key (agent PR review, CI runners). Every feature, with what it solves: what else it does.

Why not just Sentry?

Sentry is built around what the code threw, with a User Feedback widget and replay alongside. Mushi Mushi starts from what the user reported, ingests Sentry's errors too, explains each one in plain English, and hands your agent a fix prompt to start from. One queue, with or without Sentry.

It works with what you already run. Point a Sentry alert webhook at /v1/webhooks/sentry?projectId=<id> and errors land in the same queue. Once you add a Sentry auth token under Integrations → Sentry, merging a Mushi Mushi fix resolves the Sentry issue, and the reverse. Both work on every plan. Adapters also bring in Datadog, Bugsnag, Rollbar, Crashlytics and others. Plugins keep Linear, Jira, GitHub Issues, Slack, Discord, Teams and PagerDuty in sync. Nothing gets ripped out. Details: Sentry vs Mushi Mushi.

Self-host

cd deploy && cp .env.example .env   # add ANTHROPIC_API_KEY and your Supabase credentials
docker compose up -d

Walkthroughs: SELF_HOSTED.md and Docker Compose guide. Self-hosting is bring-your-own-key: you pay your LLM vendor at list price. The hosted service needs no key; it bills per diagnosis with a spend cap (pricing). Teams wiring Mushi Mushi into an existing stack (SSO, retention, region routing, Kubernetes) start at docs/operators/. Only the public api function should face the internet: see internal caller authentication.

Where it stops

_{Repo at a glance (run pnpm docs-stats): ~630K TS lines · ~2,800 source files · 45 workspace / 37 npm packages · 78 edge functions · 570 SQL migrations · 19 pipeline agents. Full tour: docs/SCREENSHOTS.md.}

Community and contributing

Questions and show-and-tell: GitHub Discussions. Bugs: Issues (first reply within 24 hours on weekdays). Security: SECURITY.md. Anything else private: kensaurus@gmail.com.

git clone https://github.com/kensaurus/mushi-mushi.git && cd mushi-mushi
pnpm install && pnpm dev   # Node ≥ 22, pnpm ≥ 10

See CONTRIBUTING.md and docs/stats.md.

License

Open core. Each package directory's own LICENSE governs that package; the root LICENSE states the split.

Self-hosting is free and complete: the repo has every feature and working default prompts. Mushi Mushi Cloud runs the same code and keeps its own tuning data (prompt wording, evaluation sets and scoring weights tuned on live traffic) as configuration. Contributions come in under a CLA. Why it is set up this way: ADR 0036. Third-party notices: NOTICE.

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The list comes from https://kensaur.us/apps.json (kensaurus/kensaur.us src/data/family.json).