The page a refusal’s type URI resolves to. Every problem this API can report has one, generated from the same catalogue row the refusal was built from.
Match on the slug — the last path segment — rather than on the whole URI: the host follows whichever deployment answered, and the slug does not.
This resource answers HEAD as well, with the same headers and no body.
It also answers OPTIONS, which returns Allow, a Link to this description, and — where the resource takes one — the query formats it reads, as Accept-Query.
The value filling {slug}, as one path segment. The API's own template spells it {+slug}, which admits several — but this resource is served by a single-segment route and answers no-such-resource for anything longer, so the OpenAPI spelling above is the exact one and nothing is lost in the translation.
curl -X GET "https://example.com/api/problems/string"
Empty
---
title: "One problem type"
description: "The page a refusal’s `type` URI resolves to. Every problem this API can report has one, generated from the same catalogue row the refusal was built from.\n\nMatch on the **slug** — the last path segment — rather than on the whole URI: the host follows whichever deployment answered, and the slug does not.\n\nThis resource answers `HEAD` as well, with the same headers and no body.\n\nIt also answers `OPTIONS`, which returns `Allow`, a `Link` to this description, and — where the resource takes one — the query formats it reads, as `Accept-Query`."
url: "https://lateano.com/developers/api/reference/discovery/problem.get"
author: "Colin Lateano"
---
# One problem type
The page a refusal’s `type` URI resolves to. Every problem this API can report has one, generated from the same catalogue row the refusal was built from.
Match on the **slug** — the last path segment — rather than on the whole URI: the host follows whichever deployment answered, and the slug does not.
This resource answers `HEAD` as well, with the same headers and no body.
It also answers `OPTIONS`, which returns `Allow`, a `Link` to this description, and — where the resource takes one — the query formats it reads, as `Accept-Query`.
```json
{
"openapi": "3.1.1",
"info": {
"title": "lateano.com",
"version": "1.0.0"
},
"paths": {
"/api/problems/{slug}": {
"get": {
"operationId": "problem.get",
"summary": "One problem type",
"tags": [
"Discovery"
],
"description": "The page a refusal’s `type` URI resolves to. Every problem this API can report has one, generated from the same catalogue row the refusal was built from.\n\nMatch on the **slug** — the last path segment — rather than on the whole URI: the host follows whichever deployment answered, and the slug does not.\n\nThis resource answers `HEAD` as well, with the same headers and no body.\n\nIt also answers `OPTIONS`, which returns `Allow`, a `Link` to this description, and — where the resource takes one — the query formats it reads, as `Accept-Query`.",
"parameters": [
{
"name": "slug",
"in": "path",
"required": true,
"schema": {
"type": "string"
},
"description": "The value filling `{slug}`, as one path segment. The API's own template spells it `{+slug}`, which admits several — but this resource is served by a single-segment route and answers `no-such-resource` for anything longer, so the OpenAPI spelling above is the exact one and nothing is lost in the translation."
}
],
"responses": {
"200": {
"description": "One problem type",
"content": {
"text/html; charset=utf-8": {}
}
},
"304": {
"description": "The representation this request already holds is still current, so it is not sent again. No body. Read the validator off `ETag` and send it back as `If-None-Match`.",
"headers": {
"etag": {
"schema": {
"type": "string"
}
},
"cache-control": {
"schema": {
"type": "string"
}
}
}
},
"default": {
"description": "Every other status this operation answers with is a refusal, and carries `problem+json` (RFC 9457).\n\nEvery refusal this API can make, whatever the status. Match on the `type` URI’s last segment — the slug below — rather than on the whole URI, which follows whichever deployment answered.\n\n| Status | Slug | Title |\n| --- | --- | --- |\n| 400 | [`invalid-idempotency-key`](https://lateano.com/api/problems/invalid-idempotency-key) | The Idempotency-Key header carries a value this resource will not accept |\n| 400 | [`malformed-body`](https://lateano.com/api/problems/malformed-body) | The request body did not parse |\n| 400 | [`missing-idempotency-key`](https://lateano.com/api/problems/missing-idempotency-key) | This resource requires an Idempotency-Key header |\n| 400 | [`missing-media-type`](https://lateano.com/api/problems/missing-media-type) | The request carried a body with no media type |\n| 404 | [`no-such-resource`](https://lateano.com/api/problems/no-such-resource) | There is nothing at this address |\n| 405 | [`method-not-allowed`](https://lateano.com/api/problems/method-not-allowed) | This resource does not answer that method |\n| 406 | [`not-acceptable`](https://lateano.com/api/problems/not-acceptable) | This resource cannot answer in any media type the request accepts |\n| 409 | [`conflicting-idempotency-key`](https://lateano.com/api/problems/conflicting-idempotency-key) | That Idempotency-Key already names a different submission |\n| 412 | [`precondition-failed`](https://lateano.com/api/problems/precondition-failed) | The condition the request carried does not hold |\n| 415 | [`unsupported-media-type`](https://lateano.com/api/problems/unsupported-media-type) | The request body is in a media type this resource does not read |\n| 422 | [`invalid-query`](https://lateano.com/api/problems/invalid-query) | The query parsed but does not describe a question this resource can answer |\n| 422 | [`invalid-submission`](https://lateano.com/api/problems/invalid-submission) | The submission parsed but is not something this resource can record |\n| 429 | [`too-many-requests`](https://lateano.com/api/problems/too-many-requests) | The courtesy quota for this caller is spent |\n| 500 | [`unexpected-failure`](https://lateano.com/api/problems/unexpected-failure) | The resource failed while answering |",
"content": {
"application/problem+json": {
"schema": {
"$ref": "#/components/schemas/ProblemDocument"
}
}
}
}
}
}
}
},
"components": {
"schemas": {
"ProblemDocument": {
"type": "object",
"properties": {
"type": {
"type": "string",
"description": "§ 3.1.1. Absolute, on the origin that answered, and it resolves."
},
"title": {
"type": "string",
"description": "§ 3.1.3. The catalogue row's, unchanged from occurrence to occurrence."
},
"status": {
"type": "number",
"description": "§ 3.1.2. The same number as the status line, derived rather than passed."
},
"instance": {
"type": "string",
"description": "§ 3.1.5 RECOMMENDS an absolute URI here. This field carries a full path from the root, which is the fallback form the same section permits."
},
"detail": {
"type": "string",
"description": "§ 3.1.4. This occurrence only, bounded by `DETAIL_MAX`, absent when there is nothing to add."
}
},
"required": [
"type",
"title",
"status",
"instance"
],
"additionalProperties": false,
"description": "The schema generator publishes this declaration as the error schema, so a field here reaches the reference. RFC 9457 § 3.1 makes all five members optional, and this API narrows four of them to required: § 3.1.1 reads an absent `type` as `about:blank` and discards the resolvable URI. An optional member is absent, never present and `undefined`, because `JSON.stringify` drops the value and the wire cannot tell the two apart."
}
}
}
}
```