Tunnel: 404

[tobiasBora]

Thanks for this great tool. The localhost mode works great, but when tunneling i get 404 errors:

❯ npx mcp-proxy --port 8034 --tunnel -- npx @mcp-b/webmcp-local-relay --port 9333
[webmcp-local-relay] WARNING: accepting connections from ALL host page origins. Use --widget-origin to restrict.
[webmcp-local-relay] server mode: listening on ws://127.0.0.1:9333 (allowed origins: *)
starting server on port 8034
establishing tunnel via tunnel.gla.ma
tunnel established at https://lazy-impala-51.tunnel.gla.ma

❯ export MCP_URL="https://lazy-impala-51.tunnel.gla.ma/mcp"
❯ curl -s -v -X POST "$MCP_URL" \
   -H "Content-Type: application/json" \
   -H "Accept: application/json, text/event-stream" \
   -d '{
     "jsonrpc": "2.0",
     "id": 1,
     "method": "initialize",
     "params": {
     "protocolVersion": "2024-11-05",
     "capabilities": {},
     "clientInfo": { "name": "curl-client", "version": "1.0.0" }
     }
     }'
Note: Unnecessary use of -X or --request, POST is already inferred.
* Host lazy-impala-51.tunnel.gla.ma:443 was resolved.
* IPv6: (none)
* IPv4: 204.10.78.179
*   Trying 204.10.78.179:443...
* ALPN: curl offers h2,http/1.1
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
* SSL Trust Anchors:
*   OpenSSL default paths (fallback)
* TLSv1.3 (IN), TLS handshake, Server hello (2):
* TLSv1.3 (IN), TLS change cipher, Change cipher spec (1):
* TLSv1.3 (IN), TLS handshake, Encrypted Extensions (8):
* TLSv1.3 (IN), TLS handshake, Certificate (11):
* TLSv1.3 (IN), TLS handshake, CERT verify (15):
* TLSv1.3 (IN), TLS handshake, Finished (20):
* TLSv1.3 (OUT), TLS change cipher, Change cipher spec (1):
* TLSv1.3 (OUT), TLS handshake, Finished (20):
* SSL connection using TLSv1.3 / TLS_AES_256_GCM_SHA384 / x25519 / id-ecPublicKey
* ALPN: server accepted h2
* Server certificate:
*   subject: CN=*.tunnel.gla.ma
*   start date: May 19 23:29:42 2026 GMT
*   expire date: Aug 17 23:29:41 2026 GMT
*   issuer: C=US; O=Let's Encrypt; CN=E7
*   Certificate level 0: Public key type EC/prime256v1 (256/128 Bits/secBits), signed using ecdsa-with-SHA384
*   Certificate level 1: Public key type EC/secp384r1 (384/192 Bits/secBits), signed using sha256WithRSAEncryption
*   Certificate level 2: Public key type RSA (4096/152 Bits/secBits), signed using sha256WithRSAEncryption
*   subjectAltName: "lazy-impala-51.tunnel.gla.ma" matches cert's "*.tunnel.gla.ma"
* SSL certificate verified via OpenSSL.
* Established connection to lazy-impala-51.tunnel.gla.ma (204.10.78.179 port 443) from 10.3.64.102 port 37526 
* using HTTP/2
* [HTTP/2] [1] OPENED stream for https://lazy-impala-51.tunnel.gla.ma/mcp
* [HTTP/2] [1] [:method: POST]
* [HTTP/2] [1] [:scheme: https]
* [HTTP/2] [1] [:authority: lazy-impala-51.tunnel.gla.ma]
* [HTTP/2] [1] [:path: /mcp]
* [HTTP/2] [1] [user-agent: curl/8.17.0]
* [HTTP/2] [1] [content-type: application/json]
* [HTTP/2] [1] [accept: application/json, text/event-stream]
* [HTTP/2] [1] [content-length: 226]
> POST /mcp HTTP/2
> Host: lazy-impala-51.tunnel.gla.ma
> User-Agent: curl/8.17.0
> Content-Type: application/json
> Accept: application/json, text/event-stream
> Content-Length: 226
> 
* upload completely sent off: 226 bytes
* TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
* TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
< HTTP/2 404 
< date: Wed, 15 Jul 2026 16:04:15 GMT
< content-length: 3
< server: Fly/6db84cd2 (2026-07-07)
< via: 2 fly.io, 2 fly.io
< fly-request-id: 01KXK8B2543E83H6E3RVMK7JQA-fra
< 
* Connection #0 to host lazy-impala-51.tunnel.gla.ma:443 left intact
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