Error 404: "no tunnel found for host"
A request to your tunnel’s host came back 404 with plain text — not JSON:
no tunnel found for host api--acme.mcppipe.devThree different conditions produce a 404, and two of them share almost the same wording. Reading the message carefully is the whole diagnosis:
| Message | Meaning |
|---|---|
no tunnel found for host <host> | The host does not match the expected pattern or the default subdomain was disabled |
no tunnel **registered** for host <host> | The host is well-formed, but no tunnel exists for it |
Note found vs registered. If you are grepping logs for the exact string, you
will land on the wrong case.
no tunnel registered for host …
Section titled “no tunnel registered for host …”The host is shaped correctly and mcppipe looked it up — there is simply no tunnel behind it. Usual causes:
- The tunnel was deleted. Deleted tunnels enter a 7-day recovery window, but they stop serving immediately.
- The subdomain or account slug was renamed, and something is still pointing at the old host.
- A typo in the host.
Check the tunnel list in the dashboard for the current public host.
no tunnel found for host … — malformed host
Section titled “no tunnel found for host … — malformed host”The host does not match the <subdomain>--<account-slug>.<zone> pattern at all.
The separator is two hyphens; a single hyphen is the most common mistake,
and it produces exactly this error.
no tunnel found for host … — default subdomain disabled
Section titled “no tunnel found for host … — default subdomain disabled”This one surprises people, because the tunnel is alive and working.
If a tunnel has a verified custom domain, its owner can disable the default
subdomain. After that, the custom domain serves normally and the original
<subdomain>--<slug>.<zone> host returns 404 on purpose — so a URL that was
handed out earlier stops working while the tunnel itself is fine.
Fix. Use the custom domain. If you want both to answer, re-enable the default subdomain in Settings.
A 404 on the custom domain itself
Section titled “A 404 on the custom domain itself”Different problem: the custom domain is probably not verified or not routable
yet. Ownership is proven with a DNS TXT record at
_mcppipe-challenge.<your-domain>, and the domain also needs its CNAME
pointing at <subdomain>--<slug>.cname.<zone>. Until both are in place the
domain does not route.
See Custom domains & TLS.
Is the CLI even connected?
Section titled “Is the CLI even connected?”A 404 is about routing — it means mcppipe could not find a tunnel for the host, which is decided before the request ever reaches your machine. If the host is right and the tunnel exists, check that the CLI is actually connected; the tunnel’s detail page shows its state.