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Stop Ignoring RFC 2324. It's the Most Important Protocol You've Never Implemented.

Pascal CESCATO on February 24, 2026

Some RFCs change the world — TCP/IP, HTTP/2, TLS 1.3. And then there's RFC 2324, published April 1st, 1998, defining the Hyper Text Coffee Pot Con...

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Aaron Rose • Feb 25

import time

def handle_brew_request(header):
    """
    Handles the critical 'BREW' method as defined in the HTCPCP.
    """
    acceptable_beverages = ["Tea", "Earl Grey", "Oolong"]

    if "Coffee" in header:
        # Strictly adhering to Section 2.3.2
        raise Exception("418 I'm a teapot: I refuse to brew coffee.")

    elif any(bev in header for bev in acceptable_beverages):
        print("Starting the infusion process...")
        time.sleep(3)  # Real-time steeping simulation
        return "200 OK: Your tea is ready. Please mind the steam."

    else:
        return "400 Bad Request: Unknown substance detected."

# Pascale would approve of this error handling
try:
    print(handle_brew_request("Content-Type: application/coffee-pot-command"))
except Exception as e:
    print(f"RFC Compliance Alert: {e}")

GnomeMan4201 • Feb 25

This post immediately reminded me of incident response energy around “network-connected appliances”

I’ve been turning some real-world security moments into a comic series called LANimals ....this one felt RFC-2324 compliant.

Pascal CESCATO • Feb 25

"We're technically under attack by standards." — that's the best incident report I've ever read.

And the honeypot returning 418 is chef's kiss — RFC 2324 §2.3.2 as a security strategy. Larry Masinter was ahead of his time.

Following LANimals immediately if is online! 🐒

Pascal CESCATO • Feb 25 • Edited

Haha Aaron, I love this — but I have to point out: you just implemented a teapot, not a coffee pot. Your server correctly returns 418 when asked to brew coffee, which means RFC 2324 §2.3.2 is fully satisfied.

You ARE the teapot.

One thing missing though: the WHEN method. Who’s going to stop the milk? 🫖

Aaron Rose • Feb 25

🤣💯

Thomas Broyer • Feb 25

The content-type should be message/coffeepot, not application/coffee-pot-command: rfc-editor.org/errata/eid682

Pascal CESCATO • Feb 25

You're absolutely right Thomas, and that's a filed errata on RFC 2324 itself — which makes this the most legitimate bug report I've ever received.

message/coffeepot is the correct Content-Type per RFC 2324 §4, and that errata exists precisely because the mistake is so easy to make. @aaron_rose_0787cc8b4775a0, you now have an official RFC errata to go with your 418.

Sylwia Laskowska • Feb 25

Awesome😄
Now I’m just waiting, Pascal, until you invent your own protocol — maybe something like a beer brewing protocol next? 🍺

Pascal CESCATO • Feb 25

Funny you should mention that, Sylwia — RFC 2324 actually defines alcohol-type as a valid Accept-Additions value. Whisky, Rum, Kahlua, Aquavit are all in spec.

The RFC already went there. I’m just following the standard. 🍺

...HTBMCP/1.0 might be next. Hyper Text Beer Mug Control Protocol. Watch this space.

klement Gunndu • Feb 27

The PROPFIND method carrying over from WebDAV into a coffee protocol is the part that ages weirdly well — it's basically discovery before discovery was a pattern. Did you handle the Safe header semantics or skip it since HTCPCP never saw real middleware?

Pascal CESCATO • Feb 27

PROPFIND as discovery predating discovery-as-a-pattern is exactly right — and it’s borrowed from WebDAV [RFC4918], which itself borrowed the concept from filesystem semantics. Masinter was essentially saying: before you BREW, ask the pot what it can do. That’s service discovery. In 1998.

On the Safe header: I skipped it, deliberately. RFC 2324 §2.2.1 defines Safe: yes | no | if-awake-user to indicate whether replaying a request is safe — borrowed from a Holtman draft that never made it to RFC. The if-awake-user conditional is the best part: safety depends on the client’s physiological state, not the server’s.

In practice it was never implemented anywhere, and HTCPCP never saw real middleware — so there was nothing to break by skipping it. But it’s the right question: a BREW is not idempotent (it decrements the pot level), so Safe: no would be the correct response header on every 200. I’ll add it as a response header in the next push. Credit where it’s due.

Harsh • Feb 25

Finally, a protocol I can truly get behind. My coffee pot has been running on vibes and prayers until now.

HTTP status code 418 (I'm a teapot) finally makes sense! Can't wait to implement this in production.

RFC 2324: Because even our coffee pots deserve REST APIs in 2026.

Pascal CESCATO • Feb 25

Haha love it Harsh — though I have to flag one RFC violation in your comment: HTCPCP is decidedly not REST. BREW is a custom method, the URI scheme is coffee://, and there’s a WHEN endpoint that stops milk pouring mid-stream.

REST would never. 🫖

Your coffee pot deserves better than REST.

Harsh • Feb 25

Haha you got me there! ☕️ Guilty as charged — I committed the ultimate sin of mixing my coffee protocols 😅

But here's my defense: When you're running on 3 cups of HTCPCP-brewed coffee at 2 AM, everything starts looking like REST!

Next time I'll make sure to use the proper coffee:// scheme and never forget the WHEN endpoint. Don't want any milk pouring disasters! 🫖

Thanks for the RFC education — my coffee pot and I will do better! 🙏

Pascal CESCATO • Feb 25

3 cups of HTCPCP-brewed coffee at 2 AM is the only valid excuse. RFC violation pardoned. ☕️☕️☕️

Guilherme Zaia • Feb 25

The TCP server workaround for uvicorn is the real move here. Most devs would've fought the framework instead of honoring the protocol layer.

One note: your pot registry lacks idempotency checks. Two concurrent BREWs on pot-1 could race. Add version tokens or CAS semantics—coffee's serious business.

Pascal CESCATO • Feb 25

Spot on, Guilherme — the TCP server wasn't stubbornness, it was the only honest move once you understand where uvicorn draws the line.

And you're absolutely right on the race condition. Two concurrent BREWs on pot-1 is a classic TOCTOU — check level, context switch, check level again, both proceed, pot goes negative. Not RFC compliant, and definitely not coffee compliant.

Fix is an asyncio.Lock() per pot in the registry, or optimistic CAS on a brew_version token:

if pot.brew_version != expected_version:
    return http_response(409, {"error": "Conflict", "hint": "Pot was modified. Retry with current version."})

409 Conflict feels like the right status here — RFC 2324 didn't define it but the spirit is there. Will push the fix. Thanks for taking the code seriously 🍵