openapi: 3.1.0
info:
  title: RSC ChemSpider Compounds Filter Tools API
  description: The RSC ChemSpider Compounds API provides programmatic access to the ChemSpider chemical database, which contains over 88 million unique chemical compounds. The API supports compound searching by name, SMILES, InChI, InChIKey, molecular formula, mass, and elemental composition. Authenticated users can retrieve compound records with detailed properties, fetch external references, images, and MOL files, and perform batch operations. A tools endpoint supports chemical format conversions and InChIKey validation. All requests require an API key obtained from the RSC Developer Portal.
  version: '1'
  contact:
    name: RSC Developer Support
    url: https://developer.rsc.org/
  termsOfService: https://www.rsc.org/legal/
servers:
- url: https://api.rsc.org/compounds/v1
  description: ChemSpider Production API
tags:
- name: Tools
  description: Chemical format conversion and validation utilities.
paths:
  /tools/convert:
    post:
      operationId: convertChemicalFormat
      summary: Convert Chemical Format
      description: 'Convert a chemical identifier from one format to another. Supported input/output formats include SMILES, InChI, InChIKey, and Mol. Valid conversion pairs include: InChI to InChIKey, InChI to Mol, InChI to SMILES, InChIKey to InChI, InChIKey to Mol, Mol to InChI, Mol to InChIKey, and SMILES to InChI.'
      tags:
      - Tools
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - input
              - inputFormat
              - outputFormat
              properties:
                input:
                  type: string
                  description: The chemical identifier to convert
                inputFormat:
                  type: string
                  description: Input format of the identifier
                  enum:
                  - SMILES
                  - InChI
                  - InChIKey
                  - Mol
                outputFormat:
                  type: string
                  description: Desired output format
                  enum:
                  - SMILES
                  - InChI
                  - InChIKey
                  - Mol
      responses:
        '200':
          description: Converted chemical identifier
          content:
            application/json:
              schema:
                type: object
                properties:
                  output:
                    type: string
                    description: The converted chemical identifier
        '400':
          description: Invalid input or unsupported conversion
        '401':
          description: Unauthorized
      security:
      - apiKeyAuth: []
  /tools/validate/inchikey:
    post:
      operationId: validateInchikey
      summary: Validate InChIKey
      description: Validate whether a given string is a correctly formed InChIKey. Returns a boolean indicating validity.
      tags:
      - Tools
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              required:
              - inchikey
              properties:
                inchikey:
                  type: string
                  description: The InChIKey string to validate
      responses:
        '200':
          description: Validation result
          content:
            application/json:
              schema:
                type: object
                properties:
                  valid:
                    type: boolean
                    description: Whether the InChIKey is valid
        '401':
          description: Unauthorized
      security:
      - apiKeyAuth: []
components:
  securitySchemes:
    apiKeyAuth:
      type: apiKey
      in: header
      name: apikey
      description: API key obtained from the RSC Developer Portal at developer.rsc.org. Register and create an application to receive an API key.