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OpenAPI Specification

openapi: 3.2.0
info:
  title: Chempirical (Nitramine) Molecules API
  version: '2026-10-09'
  description: 'GENERATED FROM DOCUMENTATION by API Evangelist on 2026-10-09: 6 operation(s) read from 1 public documentation page(s) (each operation names its page in x-source). This is not the provider''s published contract; Chempirical (Nitramine) has published no machine-readable contract that the pipeline could find. Engine: anthropic.'
  x-evidence-tiers:
    code-example: 1
    documentation: 5
    pages-with-code: 1
    pages-read: 1
  x-generated-from: documentation
  x-provenance: generated
  x-authored-by: API Evangelist
  x-generated: '2026-10-09'
  x-generator: generate-contract-from-docs.py
  x-engine: anthropic
  x-sources:
  - https://chempirical.com/api
tags:
- name: Molecules
paths:
  /api/molecules/{moleculeid}:
    get:
      operationId: get_api_molecules_moleculeid
      tags:
      - Molecules
      summary: One compound with names, formula, identifiers, molar and exact mass, density…
      x-source: https://chempirical.com/api
      parameters:
      - name: moleculeid
        in: path
        required: true
        schema:
          type: string
      responses:
        '200':
          description: Success (status as documented)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/GetApiMoleculesMoleculeidResponse'
      x-evidence:
        kind: documentation
        collapsed_from: 3 example path(s) differing only at moleculeId
    post:
      operationId: post_api_molecules_moleculeid
      tags:
      - Molecules
      summary: POST /api/molecules/64-17-5
      x-source: https://chempirical.com/api
      parameters:
      - name: moleculeid
        in: path
        required: true
        schema:
          type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/PostApiMoleculesMoleculeidRequest'
      responses:
        '201':
          description: Success (shape read from the example response on the page)
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/PostApiMoleculesMoleculeidResponse'
      x-evidence:
        kind: code-example
        language: curl
        snippet: "curl -s https://chempirical.com/api/molecules/64-17-5 | jq '.name, .properties.molar_mass_g_per_mol, .physical.boilingPoint.text'\n\"Ethanol\"\n46.069\n\"78.5 °C\" \n /api/molecules?q= \n Search compounds by name, CAS number, formula or SMILES. Parameters: q, limit (at most 200), offset. \n Example curl -s 'https://chempirical.com/api/molecules?q=caffeine&limit=2' | jq '.results[] | {cas, name, molarMass}'\n"
        collapsed_from: 2 example path(s) differing only at moleculeId
components:
  schemas:
    PostApiMoleculesMoleculeidResponse:
      type: object
      properties:
        cas:
          type: string
        name:
          type: string
        molarMass:
          type: number
    PostApiMoleculesMoleculeidRequest:
      type: object
      properties:
        terms:
          type: array
          items:
            type: string
    GetApiMoleculesMoleculeidResponse:
      type: object
      properties:
        name:
          type: string
          description: Compound name
        properties:
          type: object
          description: Compound properties including molar mass
        physical:
          type: object
          description: Physical properties including boiling point