Troubleshooting

In this scenario, it’s likely that either Mintlify cannot find your OpenAPI document, or your OpenAPI document is invalid.

Running mintlify dev locally should reveal some of these issues.

To verify your OpenAPI document will pass validation:

1. Visit this validator
2. Switch to the “Validate text” tab
3. Paste in your OpenAPI document
4. Click “Validate it!”

If the text box that appears below has a green border, your document has passed validation. This is the exact validation package Mintlify uses to validate OpenAPI documents, so if your document passes validation here, there’s a great chance the problem is elsewhere.

Additionally, Mintlify does not support OpenAPI 2.0. If your document uses this version of the specification, you could encounter this issue. You can convert your document at editor.swagger.io (under Edit > Convert to OpenAPI 3):

This is usually caused by a misspelled openapi field in the page metadata. Make sure the HTTP method and path match the HTTP method and path in the OpenAPI document exactly.

Here’s an example of how things might go wrong:

---
openapi: "GET /users/{id}/"
---

paths:
  "/users/{id}":
    get: ...

Notice that the path in the openapi field has a trailing slash, whereas the path in the OpenAPI document does not.

Another common issue is a misspelled filename. If you are specifying a particular OpenAPI document in the openapi field, ensure the filename is correct. For example, if you have two OpenAPI documents openapi/v1.json and openapi/v2.json, your metadata might look like this:

---
openapi: "v1 GET /users/{id}"
---

If you have a custom domain configured, this could be an issue with your reverse proxy. By default, requests made via the API Playground start with a POST request to the /api/request path on the docs site. If your reverse proxy is configured to only allow GET requests, then all of these requests will fail. To fix this, configure your reverse proxy to allow POST requests to the /api/request path.

Alternatively, if your reverse proxy prevents you from accepting POST requests, you can configure Mintlify to send requests directly to your backend with the api.playground.disableProxy setting in the mint.json, as described here. This will likely require you to configure CORS on your server, as these requests will now come directly from your users’ browsers.