stackexchange.similar

stable Advanced

Questions similar to a title.

GET /v1/stackexchange/similar

What you get#

A list of Stack Exchange results in Onekey's unified shape, in data (an array). An empty array is a normal, successful answer and is charged like any other; a source that reports "nothing found" as an error returns a free 404 not_found instead.

What it costs#

Advanced · 5 credits for a fresh fetch, charged only when it succeeds.
Free when served from cache (0.2 credit for a cached response over 100 KB).
Free if the request is invalid (never charged) or the source fails or reports not found (refunded).

Parameters#

Name	Type	Required	Default	What it is	Constraints
`q`	string	yes	(required)	Search query	max 200 chars; trimmed, repeated spaces collapsed
`site`	string	no	-	Stack Exchange site, default stackoverflow	max 41 chars; must match `[a-z][a-z.]{1,40}`; trimmed, lowercased

Request#

curl "https://api.onekey.dev/v1/stackexchange/similar?q=how%20to%20undo%20git%20commit" \
  -H "x-api-key: YOUR_API_KEY"

Try it

Add your key to run this call right here. No key? Get one free. The key stays in this tab.

Recorded response#

A real Stack Exchange response, recorded and returned in Onekey's shape. Fields the platform does not provide are null.

json

{
  "success": true,
  "data": [
    {
      "content": {
        "id": "56168828",
        "title": "How can I get a list of entities from existing data with ServiceStack.OrmLite?",
        "url": "https://stackoverflow.com/questions/56168828/how-can-i-get-a-list-of-entities-from-existing-data-with-servicestack-ormlite",
        "text": null,
        "createdAt": "2019-05-16T12:41:27Z"
      },
      "entity": {
        "name": "servicestack"
      },
      "engagement": {
        "likes": 1,
        "comments": 1,
        "views": 76
      },
      "author": {
        "id": "1195872",
        "username": "labilbe",
        "url": "https://stackoverflow.com/users/1195872/labilbe",
        "avatarUrl": "https://www.gravatar.com/avatar/9a1f4955d7b680bc4e08304f5b086816?s=256&d=identicon&r=PG",
        "reputation": 3565
      }
    },
    {
      "content": {
        "id": "80006527",
        "title": "How to separate the operation of getting data from the operation of reading it?",
        "url": "https://stackoverflow.com/questions/80006527/how-to-separate-the-operation-of-getting-data-from-the-operation-of-reading-it",
        "text": null,
        "createdAt": "2026-09-28T18:25:34Z"
      },
      "entity": {
        "name": "c#"
      },
      "engagement": {
        "likes": 2,
        "comments": 0,
        "views": 56
      },
      "author": {
        "id": "32514744",
        "username": "katarina zed",
        "url": "https://stackoverflow.com/users/32514744/katarina-zed",
        "avatarUrl": "https://www.gravatar.com/avatar/8852462f08e16da25e57ca7deba2085d?s=256&d=identicon&r=PG&f=y&so-version=2",
        "reputation": 413
      }
    }
  ],
  "metadata": {
    "platform": "stackexchange",
    "endpoint": "similar",
    "cached": false,
    "stale": false,
    "age_s": 0,
    "fetched_at": "2026-01-01T12:00:00+00:00",
    "credits_charged": 5,
    "request_id": "7f3a9c2e5b1d4c8fa2e6d0b9c4f18e37"
  },
  "error": null
}

Field mapping#

How this endpoint's source fields become Onekey's unified schema. Fields the source lacks come back as null.

Source path	Onekey field	Transform
`question_id`	`content.id`	`toString`
`title`	`content.title`	`htmlUnescape`
`link`	`content.url`	`safeUrl`
`body`	`content.text`	`stripHtml`
`creation_date`	`content.createdAt`	`toIsoDate`
`tags.0`	`entity.name`	-
`score`	`engagement.likes`	`toNumber`
`answer_count`	`engagement.comments`	`toNumber`
`view_count`	`engagement.views`	`toNumber`
`owner.user_id`	`author.id`	`toString`
`owner.display_name`	`author.username`	`htmlUnescape`
`owner.link`	`author.url`	`safeUrl`
`owner.profile_image`	`author.avatarUrl`	`safeUrl`
`owner.reputation`	`author.reputation`	`toNumber`

Caching and freshness#

Fresh for about 2 minutes. Repeat calls in that window are served from cache and are free.
Between 2 minutes and 15 minutes the cached copy is still served instantly and marked stale: true while Onekey refreshes it in the background.
If the source is down when a refresh is needed, the last copy can be served for up to 1 hour more (marked stale).
A "not found" is remembered for 1 minute and is free.
The cache is shared across all customers, which is what keeps repeat calls cheap.

What can go wrong#

Status	Code	What to do
401	`unauthorized`	Check the `x-api-key` header.
402	`insufficient_credits`	Add credits; your balance must cover the price.
404	`not_found`	Unknown endpoint path.
422	`invalid_params`	Fix the parameters using the table above. Free.
429	`rate_limited`	Wait `Retry-After` seconds, then retry.
502	`upstream_error`	The source failed. Refunded; retry with backoff.

See Errors for the full list and retry guidance.

Status: stable (verified against the live source).