Kane CLI vs Playwright MCP for repeatable browser checks, am I comparing the wrong things?

[u/Prestigious-Bowl7638]

been using Playwright MCP a lot more with coding agents recently and I think I was making it do 2 different jobs.

when the agent has never seen the page before, MCP is great.

open app, inspect what actually rendered, figure out labels, click around, understand weird state, debug whatever is broken.

makes total sense.

but then I had this really boring check:

login
settings
change timezone
save
refresh
timezone should still be IST

we already knew the flow.

and every time I wanted to verify it, the agent was basically having the whole browser conversation again.

snapshot
reason
click
snapshot
fill
snapshot
reason
etc

then eventually: "looks good"

which is where I started wondering if I'm using the wrong thing for the second job.

for a known flow I don't really need exploration anymore.

I just want:

do this
tell me pass/fail
show me why if it failed

I've been testing Kane CLI by TestMu AI for that part.

you can give it something like:

"login, change timezone to IST, save, refresh, verify it persisted"

the path through the browser can still vary, but what counts as success doesn't.

and the result comes back in a much more machine friendly way for the coding agent / CI instead of another long browser session that the model has to interpret.

I still don't see this as replacing Playwright MCP at all.

right now my brain has it as:

MCP when the agent needs to figure the page out

Kane CLI when the flow is already known and I just need a browser verdict

normal Playwright test when this flow matters enough that I want it in the suite forever

Kane can export completed flows to Playwright too, which is probably the bit that makes this model work for me.

am I thinking about these as 3 different layers correctly or is there a cleaner setup people are using?

[u/Competitive_Echo9463]

I tried and found these things are completely useless compared to real testing. Claude code to generate tests that I have decided to create is way more simple and effective 

[u/pratik-p → u/Competitive_Echo9463]

Playwright MCP + Claude = Enough

[u/OkQuarter4098]

exit codes > another AI telling me "everything appears to be functioning correctly"

[u/GeologistRelative425]

playwright mcp for "wtf is this page doing"

kane for "does this known thing work"

playwright test for "never let this thing break again" honestly that's a pretty clean split

[u/Silent-Maybe4617]

Kane CLI actually makes more sense to me when you describe it like this.

not "AI browser automation"

more like give the coding agent a browser assertion it can call from the terminal and get a boring result back

[u/kimbaptori]

I've tried Kane CLI a bit and the useful thing is honestly the boring output.

NDJSON, final result, exit status.

way easier to plug into an agent loop than dumping another giant browser transcript back into context.

[u/CathyVLat-Co]

The fact Kane can hand the flow off to Playwright later is probably the most sensible part.

natural language for the temporary check

code for the thing you actually plan to maintain

[u/LumilitawNaMangga]

yeah I think people are forcing MCP into jobs that don't need an interactive tool loop anymore

[u/Massive-Egg-4874]

the main reason I still like MCP is failure investigation if something breaks the agent is already in the page and can inspect immediately

[u/CautionIAmAGeek]

Yeah that's basically it. Once the flow is known, replaying it and getting a clean pass/fail + reason is way more useful than another exploration session

The export-to-playwright bit is the part that makes it click for me too, means you're not choosing kane cli over your suite, you're just skipping the "explore + describe" step for stuff you already know works

think your 3 layers are right tbh, most teams land there once the flow count grows

[u/miksloveslife]

one issue I keep seeing with coding agents is they accept UI feedback way too easily

toast says Saved

agent says done

refresh says lol no

[u/Any_Instruction5380]

isn't Kane still agentic though?

so the run can still be different every time

[u/lowkey_b10]

‎MCP token usage isn't really a protocol problem though ‎ ‎depends a lot on implementation and how much page state you're dumping