openapi: 3.2.0
info:
  title: Plinth Grants Analyze API
  summary: US foundation and nonprofit funding data from public IRS Form 990 and 990-PF filings.
  description: 'A read API over the US grantmaking universe, read from public IRS Form 990, 990-EZ and 990-PF e-file filings.


    The funder-grantee graph traverses in BOTH directions: filter by `funder_id` for everything a foundation funded, or by `recip_id` for every funder behind a nonprofit.


    Start with `/api/search` to turn an organization name into an EIN and a canonical page URL — it needs no key. Every other endpoint requires one (free tier: 50 calls a month).


    Figures are read directly from named IRS filings. The IRS releases e-file data on a 12-24 month lag, so every figure is dated to its fiscal year rather than to today. Funding relationships are reported as association, never as causation. Organizations that do not e-file may be absent.'
  version: 1.0.0
  contact:
    name: Plinth
    url: https://data.useplinth.com/developers
  license:
    name: 'Source data: IRS public domain'
    url: https://www.irs.gov/charities-non-profits/tax-exempt-organization-search-bulk-data-downloads
  termsOfService: https://www.useplinth.com/terms
servers:
- url: https://data.useplinth.com
  description: Plinth US philanthropy data
security:
- ApiKeyAuth: []
tags:
- name: Analyze
  description: Plain-English questions answered with SQL the service writes itself.
paths:
  /api/analyze:
    post:
      summary: Analyze
      operationId: askQuestion
      responses:
        '200':
          description: Successful Response
          content:
            application/json:
              schema: {}
        '401':
          $ref: '#/components/responses/Unauthorized'
        '402':
          $ref: '#/components/responses/PaymentRequired'
      description: 'Ask a question about the corpus in plain English; the service writes and runs its own SQL and streams the answer back as Server-Sent Events. Metered separately from the REST endpoints: three free questions per visitor per day, then a paid key.'
      tags:
      - Analyze
components:
  responses:
    PaymentRequired:
      description: The monthly allowance is spent, the account is inactive, or the endpoint needs a paid plan. The message says which.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ApiError'
          example:
            code: 402
            message: monthly API call allowance spent
    Unauthorized:
      description: No API key, or a key we do not recognize.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ApiError'
          example:
            code: 401
            message: missing or invalid API key
  schemas:
    ApiError:
      type: object
      description: Every failure answers with this envelope; `message` is safe to show a user.
      properties:
        code:
          type: integer
        message:
          type: string
      required:
      - code
      - message
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      in: header
      name: X-API-Key
      description: Free key includes 50 calls a month; higher volume on a paid plan. Get one at https://data.useplinth.com/pricing.
externalDocs:
  description: Developer documentation
  url: https://data.useplinth.com/developers