Space Frontiers Documents API

openapi: 3.2.0
info:
  title: Machinelibrary Ai Documents API
  version: 0.1.0
  description: 'Operations tagged Documents across 2 of this provider''s published API definitions: machinelibrary-ai-openapi.json, machinelibrary-ai-conversations-api-openapi.json. Each path carries the servers of the definition it was published in.'
servers:
- url: https://api.machinelibrary.ai
  description: Machine Library
- url: https://api.spacefrontiers.org
  description: Space Frontiers (compatible endpoint)
tags:
- name: Documents
  description: Fetch documents by ID or canonical URI.
paths:
  /v2/documents/by-uri/{uri}:
    get:
      tags:
      - Documents
      summary: Fetch a document by canonical URI, or search inside it with `text_filter`
      operationId: getDocumentByUri
      parameters:
      - name: uri
        in: path
        description: Percent-encoded canonical URI, such as doi://10.1000/example.
        required: true
        schema:
          type: string
      - name: text_filter
        in: query
        description: When present, return up to five matching passages instead of the full document. Double-quoted spans must occur verbatim in the passage.
        required: false
        schema:
          type: string
      - name: max_tokens
        in: query
        description: Return exactly the first N content tokens. Omit to return all content tokens.
        required: false
        schema:
          type: integer
          minimum: 0
      responses:
        '200':
          description: Document or in-document search results.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ByUriResponse'
        '400':
          description: Invalid URI or text filter.
        '401':
          description: Missing or invalid API credential.
        '402':
          description: Insufficient account balance.
        '404':
          description: Document not found.
      security:
      - api_key: []
      - bearer_auth: []
    servers:
    - url: https://api.machinelibrary.ai
      description: Machine Library
    - url: https://api.spacefrontiers.org
      description: Space Frontiers (compatible endpoint)
  /v2/documents/{document_id}:
    get:
      tags:
      - Documents
      summary: Fetch a document and its public metadata by Machine Library document ID
      operationId: getDocument
      parameters:
      - name: document_id
        in: path
        description: Machine Library document ID.
        required: true
        schema:
          type: string
      - name: max_tokens
        in: query
        description: Return exactly the first N content tokens. Omit to return all content tokens.
        required: false
        schema:
          type: integer
          minimum: 0
      responses:
        '200':
          description: Document content and public metadata.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/V2DocumentResponse'
        '401':
          description: Missing or invalid API credential.
        '402':
          description: Insufficient account balance.
        '404':
          description: Document not found.
      security:
      - api_key: []
      - bearer_auth: []
    servers:
    - url: https://api.machinelibrary.ai
      description: Machine Library
    - url: https://api.spacefrontiers.org
      description: Space Frontiers (compatible endpoint)
  /v2/documents/trending:
    get:
      description: Create or recompute a conversation turn using retrieved evidence. This operation can spend credits and has no general Idempotency-Key contract. After a timeout, inspect the conversation before submitting another turn. Streaming errors after headers are sent are delivered in the stream, not as a new HTTP status.
      operationId: getTrendingDocuments
      parameters:
      - description: week (default) or month.
        in: query
        name: period
        required: false
        schema:
          $ref: '#/components/schemas/TrendingPeriod'
      - description: 1..50, default 20.
        in: query
        name: limit
        required: false
        schema:
          format: int32
          minimum: 0
          type: integer
      - description: 'Only paper-like types: journal and proceedings articles, preprints and posted content, book chapters, monographs, dissertations, reports and standards.'
        in: query
        name: scholarly
        required: false
        schema:
          type: boolean
      responses:
        '200':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/TrendingResponse'
          description: Documents ordered by weighted interest, without content.
        '401':
          content:
            application/json:
              example:
                detail: Unauthorized
                status: error
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Missing or invalid credential.
          headers:
            X-Request-Id:
              description: Include this identifier when contacting support.
              schema:
                type: string
        '422':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Invalid limit or period.
          headers:
            X-Request-Id:
              description: Include this identifier when contacting support.
              schema:
                type: string
        '429':
          content:
            application/json:
              example:
                detail:
                  code: rate_limited
                  retry_after_seconds: 2
                  scope: search
                status: error
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Request budget or search capacity exhausted. Honor Retry-After and use bounded backoff.
          headers:
            Retry-After:
              description: Minimum delay in seconds before retrying this application-level rejection. Edge responses may differ.
              schema:
                minimum: 1
                type: integer
            X-Request-Id:
              description: Include this identifier when contacting support.
              schema:
                type: string
        '500':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Internal service error. Retain X-Request-Id for support; do not blindly replay writes.
          headers:
            X-Request-Id:
              description: Include this identifier when contacting support.
              schema:
                type: string
        '503':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: A required service is temporarily unavailable.
          headers:
            X-Request-Id:
              description: Include this identifier when contacting support.
              schema:
                type: string
      security:
      - api_key: []
      - bearer_auth: []
      - oauth2:
        - search
      summary: Documents with the most reader and agent interest
      tags:
      - Documents
    servers:
    - description: Machine Library
      url: https://api.machinelibrary.ai
    - description: Space Frontiers (compatible endpoint)
      url: https://api.spacefrontiers.org
  /v2/documents/{document_id}/activity:
    get:
      description: Create or recompute a conversation turn using retrieved evidence. This operation can spend credits and has no general Idempotency-Key contract. After a timeout, inspect the conversation before submitting another turn. Streaming errors after headers are sent are delivered in the stream, not as a new HTTP status.
      operationId: getDocumentActivity
      parameters:
      - description: Machine Library document ID.
        in: path
        name: document_id
        required: true
        schema:
          type: string
      responses:
        '200':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/DocumentActivityResponse'
          description: Activity counters, refreshed every 15 minutes, and live comment counts.
        '401':
          content:
            application/json:
              example:
                detail: Unauthorized
                status: error
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Missing or invalid credential.
          headers:
            X-Request-Id:
              description: Include this identifier when contacting support.
              schema:
                type: string
        '422':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Invalid document ID.
          headers:
            X-Request-Id:
              description: Include this identifier when contacting support.
              schema:
                type: string
        '429':
          content:
            application/json:
              example:
                detail:
                  code: rate_limited
                  retry_after_seconds: 2
                  scope: search
                status: error
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Request budget or search capacity exhausted. Honor Retry-After and use bounded backoff.
          headers:
            Retry-After:
              description: Minimum delay in seconds before retrying this application-level rejection. Edge responses may differ.
              schema:
                minimum: 1
                type: integer
            X-Request-Id:
              description: Include this identifier when contacting support.
              schema:
                type: string
        '500':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Internal service error. Retain X-Request-Id for support; do not blindly replay writes.
          headers:
            X-Request-Id:
              description: Include this identifier when contacting support.
              schema:
                type: string
        '503':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: A required service is temporarily unavailable.
          headers:
            X-Request-Id:
              description: Include this identifier when contacting support.
              schema:
                type: string
      security:
      - api_key: []
      - bearer_auth: []
      - oauth2:
        - search
      summary: 30- and 7-day counters for one document. All zero when it has none
      tags:
      - Documents
    servers:
    - description: Machine Library
      url: https://api.machinelibrary.ai
    - description: Space Frontiers (compatible endpoint)
      url: https://api.spacefrontiers.org
components:
  schemas:
    V2Hit:
      type: object
      required:
      - id
      - score
      - snippets
      - document
      properties:
        rrf:
          oneOf:
          - type: 'null'
          - $ref: '#/components/schemas/RrfAttribution'
        candidate_scores:
          oneOf:
          - type: 'null'
          - $ref: '#/components/schemas/CandidateScores'
        id:
          type: string
        score:
          type: number
          format: double
        snippets:
          type: array
          items:
            $ref: '#/components/schemas/Snippet'
        document: {}
    Snippet:
      type: object
      description: One highlighted passage of a search hit.
      required:
      - field
      - text
      properties:
        field:
          type: string
        text:
          type: string
        score:
          type: number
          format: double
        chunk_id:
          type:
          - integer
          - 'null'
          format: int64
        evidence:
          oneOf:
          - type: 'null'
          - $ref: '#/components/schemas/SnippetEvidence'
    RankingMode:
      type: string
      description: 'Relevance objective, independent of corpus and lexical/vector retrieval.

        Results remain document groups for both objectives.'
      enum:
      - auto
      - documents
      - passages
    FeatureContract:
      type: object
      description: Feature identity includes query construction, not only column names.
      required:
      - name
      - features
      - score_policy
      - rrf_policy
      - backfill
      - candidate_depth
      - phrase_policy
      - tokenizer_policy
      - document_reduction
      - teacher_input
      - vector_combiner
      - sparse_query
      properties:
        name:
          type: string
        features:
          type: array
          items:
            type: string
        score_policy:
          type: string
        rrf_policy:
          type: string
        backfill:
          type: boolean
        candidate_depth:
          type: integer
          format: int32
          description: Fixed per-branch, per-shard nomination depth for this feature population.
          minimum: 0
        phrase_policy:
          type: string
          description: Whole query phrase plus mean of explicit quoted-span phrase scores.
        tokenizer_policy:
          type: string
          description: Single language hint using indexed original forms when undetermined.
        document_reduction:
          type: string
        teacher_input:
          type: string
        vector_combiner:
          $ref: '#/components/schemas/VectorCombiner'
        sparse_query:
          $ref: '#/components/schemas/SparseQueryPolicy'
      additionalProperties: false
    V2SearchResponse:
      type: object
      required:
      - ranking_mode
      - hits
      - total_hits
      - has_next
      properties:
        ranking_mode:
          $ref: '#/components/schemas/RankingMode'
          description: Resolved relevance objective. Auto is a request routing policy only.
        retrieval_traces:
          type: array
          items: {}
        trajectory:
          oneOf:
          - type: 'null'
          - $ref: '#/components/schemas/SearchTrajectory'
        candidate_ranking:
          oneOf:
          - type: 'null'
          - $ref: '#/components/schemas/CandidateRankingInfo'
        hits:
          type: array
          items:
            $ref: '#/components/schemas/V2Hit'
        total_hits:
          type: integer
          format: int64
          minimum: 0
        has_next:
          type: boolean
        timings:
          oneOf:
          - type: 'null'
          - $ref: '#/components/schemas/V2Timings'
        embed_ms:
          type:
          - integer
          - 'null'
          format: int64
          minimum: 0
        corrected_query:
          type:
          - string
          - 'null'
    RankingInfo:
      type: object
      required:
      - method
      - artifact_sha256
      - model_sha256
      - feature_version
      - corpus_models
      - input_documents
      - input_rows
      - output_documents
      - elapsed_us
      - engagement
      properties:
        method:
          type: string
        artifact_sha256:
          type: string
        model_sha256:
          type: string
        feature_version:
          type: string
        corpus_models:
          type: array
          items:
            $ref: '#/components/schemas/CorpusRankingInfo'
        input_documents:
          type: integer
          minimum: 0
        input_rows:
          type: integer
          minimum: 0
        output_documents:
          type: integer
          minimum: 0
        elapsed_us:
          type: integer
          format: int64
          minimum: 0
        engagement:
          $ref: '#/components/schemas/BatchInfo'
    VectorCombiner:
      type: object
      description: 'Exact multi-value reduction used by vector nomination and document features.

        This is separate from the reduction of final L1 passage predictions.

        The v4 body-binary branch uses fixed MAX, bound by the profile name.'
      required:
      - name
      - temperature
      - top_k
      - decay
      properties:
        name:
          type: string
        temperature:
          type: number
          format: float
        top_k:
          type: integer
          format: int32
          minimum: 0
        decay:
          type: number
          format: float
      additionalProperties: false
    BatchInfo:
      type: object
      required:
      - enabled
      - as_of
      - computed_at
      - observed_documents
      - requested_documents
      - elapsed_us
      properties:
        enabled:
          type: boolean
        as_of:
          type: string
          format: date-time
        computed_at:
          type: string
          format: date-time
        observed_documents:
          type: integer
          minimum: 0
        requested_documents:
          type: integer
          minimum: 0
        elapsed_us:
          type: integer
          format: int64
          minimum: 0
    SearchTrajectory:
      type: object
      required:
      - id
      properties:
        id:
          type: string
        feedback_token:
          type:
          - string
          - 'null'
          description: A bounded, expiring capability to rate results of this retrieval.
    PredictionTarget:
      type: string
      enum:
      - teacher_score
    RrfAttribution:
      type: object
      required:
      - score
      - contributions
      properties:
        score:
          type: number
          format: float
        contributions:
          type: array
          items:
            type: object
    SparseQueryPolicy:
      type: object
      required:
      - max_query_dims
      - weight_threshold
      - heap_factor
      - pruning
      properties:
        max_query_dims:
          type: integer
          format: int32
          minimum: 0
        weight_threshold:
          type: number
          format: float
        heap_factor:
          type: number
          format: float
        pruning:
          type: number
          format: float
      additionalProperties: false
    PassageScores:
      type: object
      required:
      - ordinal
      - scores
      properties:
        ordinal:
          type: integer
          format: int32
          minimum: 0
        scores:
          type: object
          additionalProperties:
            type: number
            format: float
          propertyNames:
            type: string
        l1_score:
          type:
          - number
          - 'null'
          format: float
    CorpusRankingInfo:
      type: object
      required:
      - corpus
      - model_sha256
      - scoring
      - input_documents
      - input_rows
      properties:
        corpus:
          type: string
        model_sha256:
          type: string
        scoring:
          $ref: '#/components/schemas/Scoring'
        input_documents:
          type: integer
          minimum: 0
        input_rows:
          type: integer
          minimum: 0
    CandidateScores:
      type: object
      required:
      - document
      - passages
      - scored_passages
      properties:
        document:
          type: object
          description: Absent field data is omitted; valid zero and negative scores are retained.
          additionalProperties:
            type: number
            format: float
          propertyNames:
            type: string
        passages:
          type: array
          items:
            $ref: '#/components/schemas/PassageScores'
        scored_passages:
          type: integer
          format: int32
          minimum: 0
    Scoring:
      type: object
      required:
      - target
      - correction_weight
      properties:
        target:
          $ref: '#/components/schemas/PredictionTarget'
        correction_weight:
          type: number
          format: double
      additionalProperties: false
    V2DocumentResponse:
      type: object
      required:
      - id
      - uris
      - document
      properties:
        id:
          type: string
        uris:
          type: array
          items:
            type: string
        document: {}
    SnippetEvidence:
      type: object
      description: A reranker-selected, verbatim window within the original snippet.
      required:
      - text
      - start_char
      - score
      properties:
        text:
          type: string
        start_char:
          type: integer
          description: Unicode scalar values, relative to the full `Snippet.text`.
          minimum: 0
        score:
          type: number
          format: double
    ByUriResponse:
      oneOf:
      - $ref: '#/components/schemas/V2SearchResponse'
      - $ref: '#/components/schemas/V2DocumentResponse'
      description: 'by-uri endpoints return either a document or (with `text_filter`) a

        search response, matching the Python union return type.'
    CandidateRankingInfo:
      type: object
      required:
      - method
      - contract
      properties:
        l2:
          oneOf:
          - type: 'null'
          - $ref: '#/components/schemas/RankingInfo'
        method:
          type: string
        model_sha256:
          type:
          - string
          - 'null'
        contract:
          $ref: '#/components/schemas/FeatureContract'
    V2Timings:
      type: object
      required:
      - search_us
      - load_us
      - total_us
      properties:
        search_us:
          type: integer
          format: int64
          minimum: 0
        load_us:
          type: integer
          format: int64
          minimum: 0
        total_us:
          type: integer
          format: int64
          minimum: 0
    CommentStats:
      description: Visible comments (not deleted, approved authors) on one document.
      properties:
        comments:
          description: Comments and replies, all time.
          format: int64
          type: integer
        comments_30d:
          format: int64
          type: integer
        comments_7d:
          format: int64
          type: integer
        contributions:
          description: Comments with a kind, by kind, most comments first.
          items:
            $ref: '#/components/schemas/ContributionStats'
          type: array
        votes:
          description: Sum of votes over those comments.
          format: int64
          type: integer
      required:
      - comments
      - comments_7d
      - comments_30d
      - votes
      - contributions
      type: object
    DocumentActivity:
      properties:
        agent_reads_30d:
          format: int64
          minimum: 0
          type: integer
        agent_reads_7d:
          description: MCP agents fetched the document or searched inside it.
          format: int64
          minimum: 0
          type: integer
        ai_citations_30d:
          format: int64
          minimum: 0
          type: integer
        ai_citations_7d:
          description: Cited in generated answers.
          format: int64
          minimum: 0
          type: integer
        as_of:
          description: Snapshot time (RFC 3339); null when the document has no recorded activity.
          type:
          - string
          - 'null'
        document_id:
          type: string
        positive_ratings_30d:
          format: int64
          minimum: 0
          type: integer
        positive_ratings_7d:
          description: Relevance feedback graded 2 or 3.
          format: int64
          minimum: 0
          type: integer
        shown_30d:
          format: int64
          minimum: 0
          type: integer
        shown_7d:
          description: Times returned by authenticated searches.
          format: int64
          minimum: 0
          type: integer
        views_30d:
          format: int64
          minimum: 0
          type: integer
        views_7d:
          description: Page views, once per visitor and UTC day.
          format: int64
          minimum: 0
          type: integer
      required:
      - document_id
      - views_7d
      - views_30d
      - shown_7d
      - shown_30d
      - agent_reads_7d
      - agent_reads_30d
      - ai_citations_7d
      - ai_citations_30d
      - positive_ratings_7d
      - positive_ratings_30d
      type: object
    TrendingPeriod:
      enum:
      - week
      - month
      type: string
    TrendingDocument:
      properties:
        activity:
          $ref: '#/components/schemas/DocumentActivity'
        comments:
          $ref: '#/components/schemas/CommentStats'
        document:
          type: object
        id:
          type: string
        score:
          description: 'Weighted interest in the period: views + 2×agent reads + 3×AI

            citations + 3×positive ratings + 3×comments posted.'
          format: double
          type: number
        uris:
          items:
            type: string
          type: array
      required:
      - id
      - uris
      - document
      - activity
      - comments
      - score
      type: object
    ContributionStats:
      properties:
        comments:
          format: int64
          type: integer
        contribution:
          $ref: '#/components/schemas/Contribution'
        votes:
          description: Sum of votes over these comments.
          format: int64
          type: integer
      required:
      - contribution
      - comments
      - votes
      type: object
    Contribution:
      description: 'What a comment says about the document. The kinds do not overlap: take

        the first that applies — correction (the paper or its record is wrong),

        contradicts / supports (independent work tests the same claim), limitation

        (a weakness visible in the paper itself), related work (other work that

        neither confirms nor refutes), review (an appraisal across several points),

        question (people only). Optional for people, required for agents.'
      enum:
      - correction
      - contradicts
      - supports
      - limitation
      - related_work
      - review
      - question
      type: string
    TrendingResponse:
      properties:
        as_of:
          type:
          - string
          - 'null'
        documents:
          items:
            $ref: '#/components/schemas/TrendingDocument'
          type: array
        period:
          $ref: '#/components/schemas/TrendingPeriod'
      required:
      - period
      - documents
      type: object
    DocumentActivityResponse:
      allOf:
      - $ref: '#/components/schemas/DocumentActivity'
      - properties:
          comments:
            $ref: '#/components/schemas/CommentStats'
        required:
        - comments
        type: object
      description: Activity counters plus the document's visible comments.
    ApiError:
      properties:
        detail:
          oneOf:
          - type: string
          - additionalProperties: true
            properties:
              code:
                type: string
            type: object
        status:
          enum:
          - error
          type: string
      required:
      - status
      - detail
      type: object
  securitySchemes:
    api_key:
      type: apiKey
      in: header
      name: X-Api-Key
      description: Machine Library API key from https://machinelibrary.ai/keys.
    bearer_auth:
      type: http
      scheme: bearer
      bearerFormat: API key or OAuth 2.0 access token
      description: Send the same API key, or an OAuth 2.0 access token, as a Bearer token.
    oauth2:
      description: Authorization code with mandatory S256 PKCE. Public clients use dynamic registration; see https://machinelibrary.ai/auth.md. Access spends the consenting account's credits.
      flows:
        authorizationCode:
          authorizationUrl: https://api.machinelibrary.ai/v2/oauth/authorize
          refreshUrl: https://api.machinelibrary.ai/v2/oauth/token
          scopes:
            search: Search and retrieve research documents using your account credits.
          tokenUrl: https://api.machinelibrary.ai/v2/oauth/token
      type: oauth2
externalDocs:
  description: Authentication, limits, errors, retries, and API lifecycle
  url: https://machinelibrary.ai/docs/api/operations
x-refined-from:
- machinelibrary-ai-openapi.json
- machinelibrary-ai-conversations-api-openapi.json
x-service-info:
  categories:
  - data
  - search
  docs:
    apiReference: https://machinelibrary.ai/docs/api/reference
    homepage: https://machinelibrary.ai
    llms: https://machinelibrary.ai/llms.txt