Five46 MCP Server

five46

An autonomous AI testing agent that verifies your app or API actually works while you're still building it — fully local, using your own LLM key.

You just changed something, and you want to know — right now, against the real running thing — whether it actually works, without first writing a test yourself. Give five46 a plain-English goal — "log in and confirm the dashboard loads," "create a user via POST, then confirm it via GET" — and an LLM, using your own OpenAI, Anthropic, Gemini, Groq, or AWS Bedrock key, drives your real app or real API, one real action at a time, and tells you honestly whether it worked, with a root-cause hypothesis if it didn't. Once it does, that exact run is captured as a real, standalone Playwright (or node:test) spec you keep — so the same check that helped you while you were building the feature becomes a permanent regression test afterward, with no five46 or LLM involved in ever running it again.

Status: early proof of concept, verified end-to-end against real live LLM keys across dozens of real-world sites and APIs.

If five46 is useful to you, a ⭐ on GitHub helps other people find it — much appreciated!

Why five46, and how it's different

Most testing tools assume you already have a suite to run. five46 is built for the moment before that — mid-feature, before a test exists at all. Point it at what you're building, describe the outcome you expect in plain English, and keep re-running it as you keep changing code; once it's solid, the run it just did becomes your regression test, not a separate thing you write afterward.

Most AI-driven test-generation tools also run in a cloud sandbox: your app's traffic, screenshots, and DOM leave your machine and go through a third-party service you don't control. five46 is the opposite bet — everything runs on your laptop, using a key you already pay for, and the only thing that ever leaves your machine is the text sent to your chosen LLM provider on each step (always disclosed, never hidden). If your organization can't adopt a cloud-hosted AI testing platform for compliance or trust reasons, this is built for exactly that constraint.

It's also not a black box: every run ends with a real .spec.ts/.test.mjs file you can read, diff, commit to your repo, and run in CI with plain npx playwright test — no vendor lock-in, no proprietary runner.

Features

• Bring your own key (BYOK) — OpenAI, Anthropic, Gemini, Groq, or AWS Bedrock. Your key, your usage, your cost.
• Fully local — no cloud sandbox, no tunneling for local dev servers. Nothing but the LLM calls ever leaves your machine.
• Browser and API testing — drive a real Chromium browser, or drive real HTTP requests directly, from the same agentic engine.
• Real, standalone output — every successful run writes a plain Playwright .spec.ts (or node:test script for API tests) you can re-run any time, with no five46 or LLM involved.
• Session reuse — log in once, capture the session, reuse it across runs without paying the LLM cost of logging in every time.
• Self-healing selectors — a stale selector gets one bounded, disclosed recovery attempt instead of just failing the step.
• Resilient generated specs — when a real, live check confirms Playwright's own getByRole() resolves uniquely to the exact element a step acted on, the generated spec prefers it over a positional CSS selector, since it's far more resistant to future DOM changes. Falls back to the always-correct selector automatically wherever that check can't be made — never changes what the live run itself does.
• Root-cause hypotheses — a failed assertion gets an LLM-generated hypothesis for what likely went wrong and what to check next.
• MCP server — expose five46_test/five46_api as tools an IDE-embedded AI assistant (Claude Code, Cursor, etc.) can call directly.
• Safe by default — API testing is read-only unless you explicitly unlock writes/deletes; destructive-looking browser clicks are blocked by default too.
• Flaky-test detection — --repeat N runs the same goal N times and reports whether the outcome/behavior actually stayed the same.
• Diffing — five46 diff compares two generated run files directly.
• Project management — five46.config.json + --project for reusable, named target defaults (url, session, safety flags).
• Video replay — --record-video records the whole session as a .webm.
• Structured planning — on by default, one extra upfront LLM call plans the whole goal, then most steps execute directly against the real page/response with no further live decision needed; --no-structured-plan opts back into the fully-adaptive, live-decision-every-step loop.
• Fast per-step decisions (--fast-steps, opt-in) — on Groq/Gemini, swaps in a genuinely faster model tier for the high-frequency per-step decision only; the upfront plan always uses your configured model. No effect on OpenAI/Anthropic/Bedrock, already at their fastest reliable tier. Opt-in, not default — see "Fast per-step decisions" below.
• Story mode (--story) — splits a raw, multi-AC user story into independent goals and runs them with bounded concurrency, reporting a clear pass/fail per acceptance criterion. See "Story mode" below.

five46 vs. cloud AI testing platforms

Not a knock on cloud platforms — it's a genuinely different tradeoff (their infra vs. your own key and your own machine), and the right choice depends on what your organization is allowed to send off-machine.

Installation

npm install -g five46

npm install --save-dev playwright @playwright/test   # one-time, if your project doesn't already have it
npx playwright install chromium                       # one-time, downloads the browser

Or run it without installing globally:

npx five46 test http://localhost:3000 --goal "log in and confirm the dashboard loads"

git clone https://github.com/sekharsdet/five46.git
cd five46
npm install
npm run build
node dist/cli.js test http://localhost:3000 --goal "..."

Configuration

One-time setup (same shape as gh auth login/aws configure):

five46 config

This prompts for an LLM provider + key, masking secret input, and saves it to ~/.five46/config.json (user-only file permissions). Or set environment variables instead — these always take priority over the saved config, which is useful for CI:

export FIVE46_LLM_PROVIDER=openai   # or: anthropic, gemini, groq, bedrock
export FIVE46_LLM_API_KEY=sk-...    # for bedrock, use your AWS region instead

Getting a key

Don't have a key yet? Pick whichever's easiest to get, or whichever you already use — five46 calls one small, cheap model per provider on every step (never a "flagship" model), so per-run cost is low regardless of which one you pick. If wall-clock speed is what you care about most, pick Groq — its whole differentiator is LPU-based inference hardware built specifically for fast token generation, meaningfully faster round-trips than typical GPU-hosted inference for an equivalent-size model. Since a run's time is dominated by LLM round-trip latency (not five46's own code), the provider you pick is the single biggest lever you control over how fast a run feels:

The model each provider calls: gpt-4o-mini (OpenAI), claude-3-5-haiku-latest (Anthropic), gemini-flash-latest (Gemini), llama-3.3-70b-versatile (Groq), anthropic.claude-3-5-haiku-20241022-v1:0 (Bedrock).

AWS Bedrock is different — there's no key to paste in:

1. In the Bedrock console → Model access, request/enable access to the Claude model above, in the region you plan to use.
2. Make sure AWS credentials are available the normal way — five46 relies on the standard AWS SDK credential chain, same as the AWS CLI: aws configure, AWS_ACCESS_KEY_ID/AWS_SECRET_ACCESS_KEY env vars, or an IAM role.
3. Run five46 config, choose bedrock, and enter your region (e.g. us-east-1) when prompted — not a key.

Quick start

five46 test http://localhost:3000 --goal "log in and confirm the dashboard loads"

--goal is required. Useful flags: --max-steps (default 15), --headed (watch it drive a real visible browser instead of headless), --out (spec path), --allow-deletes (allow clicking destructive-looking elements, e.g. "Delete Account"), --no-root-cause (skip the extra LLM call that analyzes a failed assertion), --repeat N (run the goal N times and report whether it's flaky — see below), --record-video (save a .webm of the whole session), --project name (pull defaults from five46.config.json — see below), --no-structured-plan (opt out of the default upfront-plan-then-fast-path behavior and use the fully-adaptive, live-decision-every-step loop instead — see below), --fast-steps (opt-in, use a faster model for per-step decisions on Groq/Gemini — see below), --story path (split a raw multi-AC user story into independent goals and run them concurrently instead of a single --goal — see below).

A successful run writes a real, human-readable Playwright .spec.ts file containing every confirmed-working step — re-runnable any time via npx playwright test. The run itself is not deterministic (the same goal against the same page can take a different path next time); the generated spec is the frozen, repeatable artifact.

A failed assertion is reported as a real finding about the app (with a screenshot, DOM snapshot, and a root-cause hypothesis), clearly separated from a tooling hiccup (an unparseable LLM response, a stuck/repeating agent) — the two are never conflated.

Exit codes are CI-friendly: five46 test/five46 api exit 0 only when the goal was actually reached, and non-zero for anything else (a failed assertion, a stuck/looping run, a missing API key, ...) — so five46 test <url> --goal "..." || exit 1 in a CI script works as expected.

Testing behind a login

Capture a session once, reuse it across runs:

export FIVE46_LOGIN_USERNAME=...
export FIVE46_LOGIN_PASSWORD=...

five46 login https://your-app.example.com/login --goal "log in" --out session.json
five46 test https://your-app.example.com/dashboard --goal "..." --storage-state session.json

Your username/password are never sent to the LLM — the model only ever sees placeholder tokens; the real values are substituted locally at the point Playwright actually types them. session.json is itself a live bearer credential — treat it like one: don't commit it (it's written with user-only file permissions).

API/backend testing

No browser involved — the same agentic engine drives real HTTP requests toward a goal instead, and writes a real, standalone node:test script (plain node:test + node:assert + native fetch, no Playwright needed):

five46 api https://api.your-app.example.com --goal "create a user, then fetch it back and confirm the name matches"

Read-only (GET/HEAD/OPTIONS) by default. Add --allow-writes to unlock POST/PUT/PATCH, and --allow-deletes to separately unlock DELETE. Requests are restricted to the target's own origin unless you name another one via repeatable --allow-host <host>.

Listing past runs

five46 list          # current directory
five46 list ./tests  # or any other directory
five46 list --project checkout   # only runs tagged with this project

Lists previously generated five46-agent-*.spec.ts/five46-api-*.test.mjs files with their goal and outcome, most recent first. No separate "rerun" command — every generated file already is a real, standalone Playwright/ node:test file: npx playwright test <file> / node --test <file>.

Diffing two runs

five46 diff five46-agent-abc123.spec.ts five46-agent-def456.spec.ts

A plain line diff between any two generated (or other text) files, with the header's run-id token ignored (the outcome half of that same line is still compared). Exits 0 if identical, 1 if they differ.

Flaky-test detection

five46 test http://localhost:3000 --goal "..." --repeat 5

Runs the same goal N times (sequentially — capped at 10) and reports whether it's flaky: either the outcome differed across runs, or every run reached the goal but took a genuinely different path. Exits 0 only if every repeat succeeded with byte-identical generated output. Works the same way on five46 api.

Project management

// five46.config.json
{
  "projects": {
    "checkout": { "url": "http://localhost:3000/checkout", "storageState": "session.json" }
  }
}

five46 test --goal "..." --project checkout

A CLI flag always wins over a project default; a project only fills in what you didn't pass. --goal is never project-configurable. The LLM API key is never sourced from this file — only a provider label can be.

Video replay

five46 test http://localhost:3000 --goal "..." --record-video

Records the whole session as a real .webm (also available on five46 login). No special "replay" command — open the file in any video player.

Structured planning

On by default. One extra LLM call plans the whole goal upfront; most steps then execute directly against the real page/response with no further live decision — falling back to a normal live decision only when a step's prediction doesn't resolve cleanly. Same safety guarantees as an ordinary run (destructive-click gating, method/host allowlisting) are enforced independently at the fast path too, not skipped. This is the single biggest lever for cutting a run's wall-clock time, since LLM round-trip latency — not five46's own code — is the dominant per-run cost.

Confirming an outcome fast-paths too, not just navigating to it: a planned assert_visible step fast-paths under the same rule as clicks/fills (its target must resolve to exactly one real element, or it falls back to a live decision) — the visibility check itself still runs for real against the live page either way, nothing is assumed. assert_text/assert_page_text always make a live decision, since they'd also need to predict an exact expected text value for a page the plan never saw, a bigger risk than predicting an element's role/name. A well-formed goal can often complete with a single LLM call total (the upfront plan) if every step, including the final confirmation, fast-paths.

five46 test http://localhost:3000 --goal "..." --no-structured-plan

--no-structured-plan opts back into the fully-adaptive loop (a live decision every single step) — works the same way on five46 api. Note: this default applies to the test/api CLI commands only — MCP-driven runs (five46 mcp) always use the fully-adaptive loop regardless, since structured planning isn't exposed as an MCP tool parameter.

Fast per-step decisions

five46 test http://localhost:3000 --goal "..." --fast-steps

Opt-in — off by default. On Groq and Gemini, swaps in a genuinely faster model tier (llama-3.1-8b-instant, gemini-flash-lite-latest) for the high-frequency per-step action-decision call only; the one-time upfront plan (and the root-cause hypothesis call, if triggered) always use your configured model, never the fast one. On OpenAI, Anthropic, and Bedrock this flag has no effect — each is already at the fastest model tier that provider offers without risking reliability on the strict JSON-only action schema.

This is a real tradeoff, not a free win: a smaller/faster model is a genuine, currently-unquantified risk to per-step decision quality (more wrong-ref picks or retries), which is exactly why it's opt-in rather than default like structured planning. If wall-clock speed matters most to you, also consider picking Groq as your provider in the first place — see "Getting a key" above.

Story mode

five46 test http://localhost:3000 --story user-story.txt --concurrency 3

A real user story or Jira ticket often bundles several acceptance criteria together — often independent, sometimes mutually-exclusive scenarios ("checkout succeeds with valid info," "checkout fails with an invalid coupon") that can't coexist in one linear run. --story <path> reads the raw story text, splits it into independent goals with one extra upfront LLM call, then runs each one exactly like an ordinary --goal run — same safety gating, same structured planning/--fast-steps speed path, its own fresh browser session/artifact directory, its own generated spec file — with up to --concurrency running at once (default 2 for five46 test, 3 for five46 api — a real browser session against one origin carries a heavier, more bot-like footprint than a plain HTTP request, so the browser default is lower; both are hard-capped at 5). Mutually exclusive with --goal — pass exactly one. Works the same way on five46 api.

Split into 2 scenario(s):
  AC1: log in with valid credentials and complete checkout, then confirm the order confirmation is shown
  AC2: attempt checkout with no shipping details entered, then confirm a validation error is shown

=== Story mode summary ===
AC1: PASS — log in with valid credentials and complete checkout, then confirm the order confirmation is shown
AC2: PASS — attempt checkout with no shipping details entered, then confirm a validation error is shown

2/2 acceptance criteria reached goal-reached.

Exit code is all-or-nothing, matching --repeat's own CI philosophy: 0 only if every acceptance criterion reached goal-reached. Splitting is itself an LLM call and could occasionally group scenarios in an unintended way — a malformed or unusable split response degrades safely to treating the whole story as a single goal, never worse than not using --story at all.

MCP server (IDE-embedded use)

npm install --save-dev @modelcontextprotocol/sdk zod   # one-time
five46 mcp

Exposes five46_test/five46_api as MCP tools an IDE-embedded AI assistant can call directly. Read-only by default, with no per-call way to unlock writes — set FIVE46_MCP_ALLOW_WRITES=1/ FIVE46_MCP_ALLOW_DELETES=1 in the server's own environment to unlock them; tool arguments can never do it. five46 login is deliberately not exposed via MCP.

Both tools also accept an optional story field alongside goal (exactly one required) — the same story-mode splitting/bounded-concurrency described above, letting a coding agent hand over a whole multi-AC story it just implemented a feature against and get back a per-AC pass/fail. Concurrency is set via FIVE46_MCP_CONCURRENCY in the server's own environment — never a per-call tool argument, the same posture as allowWrites/allowDeletes — with the same per-tool defaults as the CLI (2 for five46_test, 3 for five46_api) when left unset, both hard-capped at 5.

Both tools also return structuredContent — a machine-parseable { passed, outcome, specPath } (or { passed, acceptanceCriteria: [...] } for a story call) alongside the existing free-text report, so a calling coding agent can branch on a real field instead of parsing prose out of the report to decide whether to rework or move on.

Known limitations

• No iframe or shadow DOM traversal — elements inside an <iframe> or a closed/open shadow root aren't visible to the agent's page snapshot today. Works fine on pages that don't rely on either.
• Chromium only for browser mode — no Firefox/WebKit yet.
• A run itself is not deterministic (the same goal against the same page can take a different path next time) — the generated spec is the frozen, repeatable artifact; see "Quick start" above.

Development

npm run build      # tsc
npm test           # build + run the test suite (node's built-in test runner)
node dist/cli.js test <url> --goal "..."

License

MIT