openapi: 3.0.1
info:
  title: USDA Ag Data Commons CKAN API
  description: >-
    The USDA Ag Data Commons is an agricultural research data repository powered
    by DKAN/CKAN. The API provides metadata discovery for datasets from USDA
    Agricultural Research Service national programs. No authentication required
    for read access.
  version: "1.0"
  contact:
    name: USDA National Agricultural Library - Ag Data Commons
    url: https://agdatacommons.nal.usda.gov
  license:
    name: CC0 1.0 Universal
    url: https://creativecommons.org/publicdomain/zero/1.0/
servers:
  - url: https://data.nal.usda.gov
security: []
tags:
  - name: Datasets
    description: Dataset metadata search and retrieval
  - name: ARS Programs
    description: ARS National Program dataset discovery
paths:
  /api/action/package_search:
    get:
      tags:
        - Datasets
      operationId: searchDatasets
      summary: Search Agricultural Research Datasets
      description: >-
        Search the Ag Data Commons catalog for agricultural research datasets.
        Returns dataset metadata including title, description, author, and
        distribution formats.
      parameters:
        - name: q
          in: query
          description: Search query string
          schema:
            type: string
          example: soil health
        - name: fq
          in: query
          description: >-
            Filter query (e.g., 'tags:"corn" organization:"ars"')
          schema:
            type: string
        - name: rows
          in: query
          description: Number of results to return (max 1000)
          schema:
            type: integer
            default: 20
            maximum: 1000
        - name: start
          in: query
          description: Offset for pagination
          schema:
            type: integer
            default: 0
        - name: sort
          in: query
          description: Sort field and direction
          schema:
            type: string
            example: score desc, metadata_modified desc
      responses:
        '200':
          description: Dataset search results
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/PackageSearchResult'
  /api/action/package_show:
    get:
      tags:
        - Datasets
      operationId: getDataset
      summary: Get Dataset by ID
      description: Retrieve full metadata for a specific dataset by its ID or name.
      parameters:
        - name: id
          in: query
          required: true
          description: Dataset ID or name slug
          schema:
            type: string
      responses:
        '200':
          description: Dataset metadata
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/PackageShowResult'
        '404':
          description: Dataset not found
  /api/action/tag_list:
    get:
      tags:
        - Datasets
      operationId: listTags
      summary: List Dataset Tags
      description: Returns a list of all tags used in the Ag Data Commons catalog.
      parameters:
        - name: vocabulary_id
          in: query
          schema:
            type: string
      responses:
        '200':
          description: List of tags
          content:
            application/json:
              schema:
                type: object
                properties:
                  success:
                    type: boolean
                  result:
                    type: array
                    items:
                      type: string
  /api/action/organization_list:
    get:
      tags:
        - Datasets
      operationId: listOrganizations
      summary: List Dataset Organizations
      description: Returns a list of organizations (e.g., ARS national programs) in the catalog.
      responses:
        '200':
          description: List of organizations
          content:
            application/json:
              schema:
                type: object
                properties:
                  success:
                    type: boolean
                  result:
                    type: array
                    items:
                      type: string
  /api/action/datastore_search:
    get:
      tags:
        - Datasets
      operationId: searchDatastoreResource
      summary: Search Datastore Resource Records
      description: >-
        Query records within a specific published dataset resource using the
        CKAN datastore. Returns tabular data rows from published datasets.
      parameters:
        - name: resource_id
          in: query
          required: true
          description: The resource ID to query
          schema:
            type: string
        - name: q
          in: query
          description: Full-text search query
          schema:
            type: string
        - name: filters
          in: query
          description: JSON object of field-value filter pairs
          schema:
            type: string
        - name: limit
          in: query
          description: Number of rows to return
          schema:
            type: integer
            default: 100
            maximum: 32000
        - name: offset
          in: query
          description: Offset for pagination
          schema:
            type: integer
            default: 0
        - name: fields
          in: query
          description: Comma-separated list of fields to return
          schema:
            type: string
        - name: sort
          in: query
          description: Comma-separated list of fields to sort by
          schema:
            type: string
      responses:
        '200':
          description: Datastore query results
          content:
            application/json:
              schema:
                type: object
                properties:
                  success:
                    type: boolean
                  result:
                    type: object
                    properties:
                      total:
                        type: integer
                      records:
                        type: array
                        items:
                          type: object
                      fields:
                        type: array
                        items:
                          type: object
components:
  schemas:
    PackageSearchResult:
      type: object
      properties:
        success:
          type: boolean
        result:
          type: object
          properties:
            count:
              type: integer
              description: Total matching datasets
            results:
              type: array
              items:
                $ref: '#/components/schemas/Dataset'
    PackageShowResult:
      type: object
      properties:
        success:
          type: boolean
        result:
          $ref: '#/components/schemas/Dataset'
    Dataset:
      type: object
      description: Agricultural research dataset metadata
      properties:
        id:
          type: string
          description: Unique dataset identifier
        name:
          type: string
          description: URL-safe name slug
        title:
          type: string
          description: Dataset title
        notes:
          type: string
          nullable: true
          description: Description of the dataset
        author:
          type: string
          nullable: true
          description: Dataset author(s)
        author_email:
          type: string
          nullable: true
        organization:
          type: object
          nullable: true
          description: Organization (ARS national program)
          properties:
            name:
              type: string
            title:
              type: string
        tags:
          type: array
          items:
            type: object
            properties:
              name:
                type: string
              display_name:
                type: string
        resources:
          type: array
          description: Data files and distribution links
          items:
            $ref: '#/components/schemas/Resource'
        metadata_created:
          type: string
          format: date-time
        metadata_modified:
          type: string
          format: date-time
        license_title:
          type: string
          nullable: true
    Resource:
      type: object
      description: A data file or distribution of a dataset
      properties:
        id:
          type: string
        name:
          type: string
        description:
          type: string
          nullable: true
        url:
          type: string
          format: uri
        format:
          type: string
          description: File format (CSV, JSON, GeoTIFF, etc.)
        size:
          type: integer
          nullable: true
        created:
          type: string
          format: date-time
        last_modified:
          type: string
          format: date-time
          nullable: true