manifold.market_by_slug

stable Standard

One Manifold market by slug.

GET /v1/manifold/market_by_slug

What you get#

One Manifold record in Onekey's unified shape, in data. If the record does not exist you get a 404 not_found and are not charged.

What it costs#

Standard · 1 credit 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
`slug`	string	yes	(required)	Market slug	max 121 chars; must match `[a-z0-9][a-z0-9-]{0,120}`; trimmed, lowercased

Request#

curl "https://api.onekey.dev/v1/manifold/market_by_slug?slug=will-republicans-win-the-senate-in-738388924521" \
  -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 Manifold response, recorded and returned in Onekey's shape. Fields the platform does not provide are null.

json

{
  "success": true,
  "data": {
    "entity": {
      "id": "BpoEJNtlQoDBpfjBmK0y",
      "name": "Will Republicans win the Senate in the 2026 elections?",
      "url": "https://manifold.markets/AndrewG/will-republicans-win-the-senate-in-738388924521",
      "slug": "will-republicans-win-the-senate-in-738388924521",
      "category": "BINARY",
      "createdAt": "2022-12-08T18:07:28Z",
      "date": "2026-12-01T04:59:00Z"
    },
    "market": {
      "probability": 0.3595430873419773,
      "volume": 236063.09899401467,
      "volume24h": 2695.2403780852164,
      "liquidity": 20005
    },
    "ext": {
      "bettors": 534,
      "resolved": false
    },
    "author": {
      "username": "AndrewG",
      "displayName": "Andrew G",
      "id": "H6b5PWELWfRV6HhyHAlCGq7yJJu2",
      "avatarUrl": "https://lh3.googleusercontent.com/a-/AOh14GiaKzvDVGOvUXFxGChB6G4D9spo8N6MGUqFjIRTqAk=s96-c"
    }
  },
  "metadata": {
    "platform": "manifold",
    "endpoint": "market_by_slug",
    "cached": false,
    "stale": false,
    "age_s": 0,
    "fetched_at": "2026-01-01T12:00:00+00:00",
    "credits_charged": 1,
    "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
`id`	`entity.id`	-
`question`	`entity.name`	-
`url`	`entity.url`	`safeUrl`
`slug`	`entity.slug`	-
`outcomeType`	`entity.category`	-
`createdTime`	`entity.createdAt`	`toIsoDate`
`closeTime`	`entity.date`	`toIsoDate`
`probability`	`market.probability`	`toNumber`
`volume`	`market.volume`	`toNumber`
`volume24Hours`	`market.volume24h`	`toNumber`
`totalLiquidity`	`market.liquidity`	`toNumber`
`uniqueBettorCount`	`ext.bettors`	`toNumber`
`isResolved`	`ext.resolved`	`toBoolean`
`creatorUsername`	`author.username`	-
`creatorName`	`author.displayName`	-
`creatorId`	`author.id`	-
`creatorAvatarUrl`	`author.avatarUrl`	`safeUrl`

Caching and freshness#

Fresh for about 30 minutes. Repeat calls in that window are served from cache and are free.
Between 30 minutes and 6 hours 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 day more (marked stale).
A "not found" is remembered for 5 minutes 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`	That record does not exist. Free; do not retry.
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).