How to use parameters and responses?

Nobody has claimed this yet.

I'm trying to use this project to document our API, and the code from the readme.md works just fine. But I cannot figure out how to add parameters and responses.

The code below, as is, works. But when I uncomment one of the lines with the response I get errors.

#### Second line uncommented:

```
# dune exec ./hello.exe
File "hello.ml", line 36, characters 43-65:
36 | ~responses:[(OpenRouter.response "200" {description = "lala"})]
^^^^^^^^^^^^^^^^^^^^^^
Error: This expression should not be a record, the expected type is
Openapi_router__.Spec.response_object
Openapi_router__.Json_schema.or_ref
```
I would have expected ocaml to convert the type.

#### First line uncommented:

```
# dune exec ./hello.exe
File "hello.ml", line 35, characters 43-66:
35 | ~responses:[(OpenRouter.response "200" "{description: 'lala'}")]
^^^^^^^^^^^^^^^^^^^^^^^
Error: This expression has type string but an expression was expected of type
Openapi_router.Spec.response_object
Openapi_router__Json_schema.or_ref
```
I would have expected yojson to parse this, and that it works.

#### Actual code

In the actual code, I'm getting a somewhat different error, which suggests that yojson is actually working, but the type is for some reason wrong. It includes the `-> OpenRouter.t -> OpenRouter.t` part, which is in the definition, but not expected. This is also confusing.

```
dune exec ./hallo.exe
File "hallo.ml", line 165, characters 17-56:
165 | ~parameters:[(OpenRouter.parameter "{name: 'lala'}")]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Error (warning 5 [ignored-partial-application]): this function application is partial,
maybe some arguments are missing.
File "hallo.ml", line 165, characters 17-56:
165 | ~parameters:[(OpenRouter.parameter "{name: 'lala'}")]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Error: This expression has type
Openapi_router.Spec.parameter_object
Openapi_router__Json_schema.or_ref -> OpenRouter.t -> OpenRouter.t
but an expression was expected of type
Openapi_router.Spec.parameter_object
Openapi_router__Json_schema.or_ref
```

If you want I can try and trim down the actual code. It's currently just very bloated with types and stuff, which just distracts.

I would appreciate any example showing how parameters and responses should be declared. Also maybe a short explanation on how to map parameters from the `~parameters` to the ones automatically extracted from the path.

---
Here is my code:

```
module Config = struct
type app = Dream.handler
type route = Dream.route
type handler = Dream.handler

let json_path = "/openapi.json"
let doc_path = "/docs"

let json_route json = Dream.get json_path (fun _ -> Dream.json json)

let doc_route html = Dream.get doc_path (fun _ -> Dream.html html)

let get = Dream.get
let post = Dream.post
let delete = Dream.delete
let put = Dream.put
let options = Dream.options
let head = Dream.head
let patch = Dream.patch

let build_routes = Dream.router
end

module OpenRouter = Openapi_router.Make (Config)

let circumference = fun request ->
Dream.html (
let radius = (float_of_string (Dream.param request "radius")) in
(string_of_float (Float.mul 6.28 radius)))

let start () =
OpenRouter.empty
|> OpenRouter.description "My app description"
|> OpenRouter.get ~description:"Circles and suff"
(* ~responses:[(OpenRouter.response "200" "{description: 'lala'}")] *)
(* ~responses:[(OpenRouter.response "200" {description = "lala"})] *)
"/circumference/:radius" circumference
|> OpenRouter.build
|> Dream.logger
|> Dream.run ~interface:"0.0.0.0" ~port:8080

let () = start ()
```

Start with README.md and the OpenRouter.response and OpenRouter.parameter calls shown in hello.ml and hallo.ml. Trace the expected response_object and parameter_object types to determine how parameters and responses are declared and how path parameters are mapped. Done means adding a concise working example and explanation for both uses.

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