openapi: 3.2.0
info:
  title: 0xArchive HIP-4 Outcomes - Outcomes API
  description: REST API for current and historical market data from Hyperliquid and Lighter. Hyperliquid coverage includes core perpetuals, Spot, HIP-3 builder perpetuals, and HIP-4 outcome markets. Coverage and access requirements vary by route. See https://docs.0xarchive.io/ for authentication, limits, and examples.
  version: 1.6.1
  termsOfService: https://0xarchive.io/terms
  contact:
    name: 0xArchive Support
    url: https://0xarchive.io
    email: support@0xarchive.io
  license:
    name: Proprietary
    url: https://0xarchive.io/terms
servers:
- url: https://api.0xarchive.io
  description: Production API
security:
- ApiKeyAuth: []
tags:
- name: HIP-4 Outcomes - Outcomes
  description: HIP-4 outcome market discovery (one row per outcome, both sides combined). Use these to enumerate live and settled binary outcome markets. Data from May 2026.
paths:
  /v1/hyperliquid/hip4/outcomes:
    get:
      tags:
      - HIP-4 Outcomes - Outcomes
      summary: List HIP-4 outcomes
      description: List HIP-4 outcome markets (one row per outcome, both sides combined). Optional `is_settled` filter. Cursor pagination. Response uses `Hip4OutcomeAggregate` and OMITS the `aggregated_oi` field. Use `/outcomes/{outcome_id}` to fetch a single outcome with `aggregated_oi` populated. Data available from May 2026.
      operationId: listHip4Outcomes
      parameters:
      - name: is_settled
        in: query
        description: Filter by settlement status. Omit to return both live and settled outcomes.
        schema:
          type: boolean
      - name: cursor
        in: query
        description: Cursor for pagination (use the value from previous response's `next_cursor`)
        schema:
          type: string
      - name: limit
        in: query
        description: 'Maximum number of results (default: 100, max: 1000)'
        schema:
          type: integer
          default: 100
          maximum: 1000
      security:
      - ApiKeyAuth: []
      responses:
        '200':
          description: List of HIP-4 outcomes (without `aggregated_oi`)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiResponseHip4OutcomeAggregateArray'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '429':
          $ref: '#/components/responses/RateLimited'
  /v1/hyperliquid/hip4/outcomes/{outcome_id}:
    get:
      tags:
      - HIP-4 Outcomes - Outcomes
      summary: Get HIP-4 outcome detail
      description: 'Get a single HIP-4 outcome by `outcome_id`. Response uses `Hip4OutcomeAggregate` WITH `aggregated_oi` populated: latest both-sides OI snapshot including `outcome_display_open_interest_contracts` (sum of side0 + side1), `paired_set_supply_contracts` (paired-set notional), and `side_supply_parity` (whether side0 == side1 within tolerance). Currency is always `USDH`. Data available from May 2026.'
      operationId: getHip4Outcome
      parameters:
      - name: outcome_id
        in: path
        required: true
        description: 'Numeric outcome ID (integer >= 0). Each outcome has two sides: side 0 (Yes) and side 1 (No).'
        schema:
          type: integer
          format: int64
          example: 0
        example: 0
      security:
      - ApiKeyAuth: []
      responses:
        '200':
          description: HIP-4 outcome detail (with `aggregated_oi`)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiResponseHip4OutcomeAggregate'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
        '429':
          $ref: '#/components/responses/RateLimited'
  /v1/hyperliquid/hip4/outcomes/by-slug/{slug}:
    get:
      tags:
      - HIP-4 Outcomes - Outcomes
      summary: Get HIP-4 outcome by slug
      description: Look up a HIP-4 outcome aggregate by synthesized outcome slug or side slug, for example `btc-above-78213-may-04-0600` or `btc-above-78213-yes-may-04-0600`. Returns the same aggregate shape as `/outcomes/{outcome_id}` with `aggregated_oi` populated when available.
      operationId: getHip4OutcomeBySlug
      parameters:
      - name: slug
        in: path
        required: true
        description: HIP-4 outcome or side slug.
        schema:
          type: string
          example: btc-above-78213-may-04-0600
        example: btc-above-78213-may-04-0600
      responses:
        '200':
          description: HIP-4 outcome aggregate
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiResponseHip4OutcomeAggregate'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '429':
          $ref: '#/components/responses/RateLimited'
components:
  schemas:
    ApiMeta:
      type: object
      description: Response metadata
      properties:
        count:
          type: integer
          description: Number of records returned
        next_cursor:
          type:
          - string
          - 'null'
          description: Cursor for pagination (timestamp). Use this value as the `cursor` parameter to fetch the next page of results.
        request_id:
          type: string
          format: uuid
          description: Unique request ID for support
        coverage_from:
          type: string
          format: date-time
          description: Earliest coverage for the requested symbol and data type. Present only when the requested window ends before coverage begins.
        notice:
          type: string
          description: Human-readable advisory about the response. Currently used when the requested window ends before coverage begins for the symbol; may carry other advisories in future.
    ApiResponseHip4OutcomeAggregateArray:
      type: object
      description: API response wrapping an array of HIP-4 outcome aggregates (without `aggregated_oi`; use `/outcomes/{outcome_id}` for the detail variant)
      properties:
        success:
          type: boolean
          example: true
        data:
          type: array
          items:
            $ref: '#/components/schemas/Hip4OutcomeAggregate'
        meta:
          $ref: '#/components/schemas/ApiMeta'
    Hip4OutcomeAggregate:
      type: object
      description: Per-outcome aggregate (both sides combined). Returned by `/outcomes` (list, without `aggregated_oi`) and `/outcomes/{outcome_id}` (detail, with `aggregated_oi` populated).
      required:
      - outcome_id
      - side_specs
      - is_settled
      properties:
        outcome_id:
          type: integer
          format: int64
          description: Numeric outcome identifier
          example: 0
        name:
          type:
          - string
          - 'null'
          description: Human-readable outcome name (without per-side suffix)
          example: BTC ≥ 78213 by 2026-05-03 06:00 UTC
        description_raw:
          type:
          - string
          - 'null'
          description: Pipe-delimited recurring-market metadata as emitted upstream
          example: class:priceBinary|underlying:BTC|expiry:20260503-0600|targetPrice:78213|period:1d
        class:
          type:
          - string
          - 'null'
          description: Outcome class (e.g., `priceBinary`)
          example: priceBinary
        underlying:
          type:
          - string
          - 'null'
          description: Underlying asset for recurring price-binary outcomes
          example: BTC
        expiry:
          type:
          - string
          - 'null'
          format: date-time
          description: Settlement timestamp (UTC)
          example: '2026-05-03T06:00:00Z'
        target_price:
          type:
          - number
          - 'null'
          description: Target price for the binary outcome
          example: 78213
        period:
          type:
          - string
          - 'null'
          description: Cadence of the recurring market (e.g., `1d`, `1h`)
          example: 1d
        side_specs:
          type: array
          description: 'Per-side specs. Typically two elements: side 0 (Yes) and side 1 (No).'
          items:
            $ref: '#/components/schemas/Hip4SideSpec'
        is_settled:
          type: boolean
          description: Whether the outcome has settled
          example: false
        status:
          type:
          - string
          - 'null'
          description: Lifecycle status (`live`, `settled`, ...)
          example: live
        source_seen_at:
          type:
          - string
          - 'null'
          format: date-time
          description: Last time the outcome was seen upstream
          example: '2026-05-02T20:25:00Z'
        aggregated_oi:
          allOf:
          - $ref: '#/components/schemas/Hip4AggregatedOi'
          description: Display/paired/parity OI aggregates. Populated ONLY on the `/outcomes/{outcome_id}` detail response. Omitted (or null) on the `/outcomes` list response.
    ApiResponseHip4OutcomeAggregate:
      type: object
      description: API response wrapping a single HIP-4 outcome aggregate (with `aggregated_oi` populated on the detail endpoint)
      properties:
        success:
          type: boolean
          example: true
        data:
          $ref: '#/components/schemas/Hip4OutcomeAggregate'
        meta:
          $ref: '#/components/schemas/ApiMeta'
    Hip4AggregatedOi:
      type: object
      description: Derived OI display fields combining both sides of a HIP-4 outcome. Currency is always `USDH` (Hyperliquid's stablecoin). Only populated on `/outcomes/{outcome_id}` (detail), NOT on `/outcomes` (list).
      required:
      - currency
      properties:
        side0_open_interest_contracts:
          type:
          - number
          - 'null'
          description: Latest open-interest contracts for side 0 (Yes)
          example: 568048
        side1_open_interest_contracts:
          type:
          - number
          - 'null'
          description: Latest open-interest contracts for side 1 (No)
          example: 568048
        outcome_display_open_interest_contracts:
          type:
          - number
          - 'null'
          description: 'Display total: sum of side0 + side1 OI contracts. Use this for outcome-level OI dashboards.'
          example: 1136096
        paired_set_supply_contracts:
          type:
          - number
          - 'null'
          description: 'Paired-set supply: minimum of side0 and side1 OI contracts. Represents the count of fully collateralized Yes+No pairs in circulation.'
          example: 568048
        side_supply_parity:
          type:
          - boolean
          - 'null'
          description: True when side0 OI equals side1 OI within tolerance. Parity should hold for binary outcomes; a sustained false value indicates ingestion drift.
          example: true
        currency:
          type: string
          description: Notional currency. Always `USDH` for HIP-4.
          enum:
          - USDH
          example: USDH
        as_of:
          type:
          - string
          - 'null'
          format: date-time
          description: Latest timestamp across both sides
          example: '2026-05-02T20:27:21Z'
        side0_as_of:
          type:
          - string
          - 'null'
          format: date-time
          description: Timestamp of the side 0 OI sample
          example: '2026-05-02T20:27:21Z'
        side1_as_of:
          type:
          - string
          - 'null'
          format: date-time
          description: Timestamp of the side 1 OI sample
          example: '2026-05-02T20:27:21Z'
    Error:
      type: object
      description: Error response
      properties:
        code:
          type: integer
          description: HTTP status code
        error:
          type: string
          description: Error message
        error_code:
          type: string
          description: 'Machine-readable error code. Common values: `invalid_query_params` (a query parameter failed to parse or validate) and `invalid_path_params` (a path parameter failed to parse). Other endpoint-specific codes exist; treat unknown codes as generic errors of the given HTTP status.'
        request_id:
          type: string
          format: uuid
          description: Unique request ID for support
    Hip4SideSpec:
      type: object
      description: 'Per-side spec nested in `Hip4OutcomeAggregate.side_specs`. One element per side (typically two: side 0 = Yes, side 1 = No).'
      required:
      - side
      - name
      - coin
      - asset_id
      properties:
        side:
          type: integer
          description: 'Side index: 0 = Yes, 1 = No'
          enum:
          - 0
          - 1
          example: 0
        name:
          type: string
          description: Human label for this side
          example: 'Yes'
        coin:
          type: string
          description: Coin identifier for this side. Returned in `#`-prefixed form. REST paths accept either the bare numeric id (e.g. `0`) or the `#`-prefixed form (e.g. `#0`).
          example: '#0'
        asset_id:
          type: integer
          format: int64
          description: Public asset ID for this side
          example: 100000000
  responses:
    Unauthorized:
      description: Authentication required
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            code: 401
            error: Missing or invalid API key. Provide X-API-Key header.
    BadRequest:
      description: Invalid request
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            code: 400
            error: 'Failed to deserialize query string: limit: invalid digit found in string'
            error_code: invalid_query_params
            request_id: 3f2a9c71-5b0e-4d68-9a4c-7e1d2b6f8a05
    RateLimited:
      description: Rate limit exceeded
      headers:
        X-RateLimit-Limit:
          schema:
            type: integer
          description: Requests per second limit
        X-RateLimit-Remaining:
          schema:
            type: integer
          description: Remaining requests this second
        X-RateLimit-Reset:
          schema:
            type: integer
          description: Unix timestamp when limit resets
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            code: 429
            error: Rate limit exceeded
    NotFound:
      description: Resource not found
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            code: 404
            error: Resource not found
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      in: header
      name: X-API-Key
      description: API key for authentication. Get yours at https://0xarchive.io/dashboard
externalDocs:
  description: 0xArchive Developer Docs
  url: https://docs.0xarchive.io/
x-0xarchive-docs-language-overlay:
  name: data-quality-supported-venue-language
  reason: Public OpenAPI language must describe supported venue-family coverage instead of broad exchange coverage.
  updated_at: '2026-05-24'
  remove_when: Public source OpenAPI uses supported venue-family wording for data-quality coverage and latency descriptions.
x-0xarchive-docs-overlay:
  name: hyperliquid-spot
  reason: Hyperliquid Spot routes are included in the local REST contract.
  source: live endpoint behavior and public CLI/MCP/Skill surface truth
  updated_at: '2026-05-08'
  remove_when: Public source contract includes the same Spot route family.