openapi: 3.0.3
info:
  title: ChEMBL Data REST Activity Assay API
  description: ChEMBL is a manually curated database of bioactive molecules with drug-like properties, maintained by the EMBL-EBI. This REST API provides programmatic access to bioactive molecules, drug targets, bioactivity measurements, approved drugs, assay data, and clinical trial compound information. ChEMBL_37 contains over 2.9 million distinct compounds, 24.5 million activities, and 18,552 targets.
  version: ChEMBL_37
  contact:
    name: ChEMBL Team
    email: chembl-help@ebi.ac.uk
    url: https://www.ebi.ac.uk/chembl/
  license:
    name: Creative Commons Attribution-ShareAlike 3.0 Unported
    url: https://creativecommons.org/licenses/by-sa/3.0/
  termsOfService: https://www.ebi.ac.uk/about/terms-of-use/
  x-logo:
    url: https://www.ebi.ac.uk/chembl/static/chembl/img/chembl_logo.png
servers:
- url: https://www.ebi.ac.uk/chembl/api/data
  description: ChEMBL Production API Server
tags:
- name: Assay
  description: Experimental protocols and result details from source documents and datasets.
paths:
  /assay:
    get:
      tags:
      - Assay
      summary: List assays
      description: Retrieve a paginated list of assays. Each assay describes an experimental protocol and associated results from source documents.
      operationId: listAssays
      parameters:
      - $ref: '#/components/parameters/format'
      - $ref: '#/components/parameters/limit'
      - $ref: '#/components/parameters/offset'
      - name: assay_chembl_id
        in: query
        description: Filter by ChEMBL assay ID
        schema:
          type: string
      - name: assay_type
        in: query
        description: Filter by assay type
        schema:
          type: string
          enum:
          - B
          - F
          - A
          - T
          - P
          - U
      - name: target_chembl_id
        in: query
        description: Filter by target ChEMBL ID
        schema:
          type: string
      responses:
        '200':
          description: Paginated list of assays
          content:
            application/json:
              schema:
                type: object
                properties:
                  meta:
                    $ref: '#/components/schemas/Meta'
                  assays:
                    type: array
                    items:
                      $ref: '#/components/schemas/Assay'
        '400':
          $ref: '#/components/responses/BadRequest'
        '404':
          $ref: '#/components/responses/NotFound'
  /assay/{assay_chembl_id}:
    get:
      tags:
      - Assay
      summary: Get assay by ChEMBL ID
      description: Retrieve a single assay by its ChEMBL ID.
      operationId: getAssay
      parameters:
      - name: assay_chembl_id
        in: path
        required: true
        description: ChEMBL ID of the assay
        schema:
          type: string
          example: CHEMBL1909072
      - $ref: '#/components/parameters/format'
      responses:
        '200':
          description: Assay record
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Assay'
        '404':
          $ref: '#/components/responses/NotFound'
components:
  parameters:
    offset:
      name: offset
      in: query
      description: Number of records to skip for pagination
      schema:
        type: integer
        default: 0
        minimum: 0
    format:
      name: format
      in: query
      description: Response format
      schema:
        type: string
        enum:
        - json
        - xml
        - yaml
        - jsonp
        default: json
    limit:
      name: limit
      in: query
      description: Number of records to return per page (default 20, max 1000)
      schema:
        type: integer
        default: 20
        maximum: 1000
        minimum: 1
  schemas:
    Error:
      type: object
      properties:
        error_message:
          type: string
        status:
          type: string
    Meta:
      type: object
      description: Pagination metadata for list responses
      properties:
        limit:
          type: integer
          description: Number of records returned per page
        next:
          type: string
          nullable: true
          description: URL for the next page of results
        offset:
          type: integer
          description: Number of records skipped
        previous:
          type: string
          nullable: true
          description: URL for the previous page of results
        total_count:
          type: integer
          description: Total number of records matching the query
    Assay:
      type: object
      description: An experimental assay describing the protocol used to measure bioactivity
      properties:
        assay_category:
          type: string
          nullable: true
          description: Assay category (e.g., screening, confirmatory, summary)
        assay_cell_type:
          type: string
          nullable: true
          description: Cell type used in the assay
        assay_chembl_id:
          type: string
          description: Unique ChEMBL ID for the assay
        assay_description:
          type: string
          description: Description of the assay as curated from the source document
        assay_organism:
          type: string
          nullable: true
          description: Organism from which the assay target comes
        assay_strain:
          type: string
          nullable: true
          description: Strain of organism used in the assay
        assay_subcellular_fraction:
          type: string
          nullable: true
          description: Subcellular fraction used in the assay
        assay_tax_id:
          type: string
          nullable: true
          description: NCBI taxonomy ID of the assay organism
        assay_tissue:
          type: string
          nullable: true
          description: Tissue from which the assay is derived
        assay_type:
          type: string
          description: Assay type code
        assay_type_description:
          type: string
          nullable: true
          description: Description of the assay type
        bao_format:
          type: string
          nullable: true
          description: BioAssay Ontology format classification
        bao_label:
          type: string
          nullable: true
          description: BioAssay Ontology format label
        document_chembl_id:
          type: string
          description: ChEMBL ID of the source document
        relationship_description:
          type: string
          nullable: true
          description: Description of the target-assay relationship
        relationship_type:
          type: string
          nullable: true
          description: Relationship between the assay and its molecular target
        src_assay_id:
          type: string
          nullable: true
          description: Assay ID from the source database
        src_id:
          type: integer
          nullable: true
          description: Source database ID
        target_chembl_id:
          type: string
          nullable: true
          description: ChEMBL ID of the assay target
        tissue_chembl_id:
          type: string
          nullable: true
          description: ChEMBL ID of the tissue
        variant_sequence:
          type: string
          nullable: true
          description: Sequence mutation information for variant assays
  responses:
    BadRequest:
      description: Bad request - invalid query parameters
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    NotFound:
      description: Resource not found
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
externalDocs:
  description: ChEMBL Web Services Documentation
  url: https://chembl.gitbook.io/chembl-interface-documentation/web-services/chembl-data-web-services