GPT Actions says it got a blank response, but it never contacts my server

Hello, I’m trying to create my first customGPT that uses an action to hit my server. I have a GPT subscription.

When I try to test the function, it asks for permission to contact my server, I click “allow”, from both web and mobile. It then says:

[debug] Response received
Error talking to
There appears to be a persistent issue with the API. 

I believe I’ve configured things correctly. I have the domain and path set correctly. I’m serving the path as “linkgen.php” from an apache server running on ec2. I have a valid signed SSL certificate.

Nothing shows up in my access logs when gpt says it’s trying to connect. When I hit that path from my browser, it works perfectly and shows up in my access logs.

it looks like GPT is just refusing to connect to the server, with no indication as to why or other steps to take.

Is there a good way to debug this, or any other good sites or chat servers for custom GPT developers?

Here is my config, based totally on the weather example schema

"openapi": "3.1.0",
"info": {
    "title": "Link Generator",
    "description": "Generates a URL based on input parameters.",
    "version": "v1.0.0"
"servers": [
    "url": ""
"paths": {
    "/linkgen.php": {
    "get": {
        "description": "Generate a URL based on input",
        "operationId": "GenerateLink",
        "parameters": [
            "name": "v",
            "in": "query",
            "description": "The input value to generate the URL",
            "required": true,
            "schema": {
            "type": "string"
        "deprecated": false
"components": {
    "schemas": {}

What does the debug request information say?

  "domain": "URL",
  "method": "get",
  "path": "/linkgen.php",
  "operation": "GenerateLink",
  "operation_hash": "8c35972ea19897558b470ed6e8f45ff3d152f2f6",
  "is_consequential": false,
  "params": {
    "v": "test"

It’s not possible to tell because you’re redacting your URL, but does your URL by chance end with a /?

Also, check to ensure your domain has propagated to the closure DNS with,

dig @ <your domain>

In the schema, it is in the form:

“url”: “httpsCOLON//wwwDOTmyurlDOTcom” (this board blocks anything that looks like a link)

no trailing slash, nor in the debug request.

My domain has been up for 10+ years with the same DNS and IP.

I made a new post, but it seems that the SSLv3(deprecated) handshake is failing and didn’t make it into my logs

Given I have a pretty default apache / SSL cert setup, not sure what issue is, but looking into it.

Turns out that I had the following in my apache config:

Which has worked for me for all my current API / webserving usage, but this fixed the SSLv3 handshake by adding the following: SSLCertificateChainFile

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