Harmonic REST & GraphQL API

REST API for company search, enrichment, saved searches, list management, and bulk operations, plus a full GraphQL endpoint for flexible queries across companies, people, investors, lists, and custom fields. Auth via apikey header or OAuth 2.0 bearer tokens.

Operations 39

GET /companies Batch Get Company By Id Or Urn #
POST /companies Get Company By Identifiers #
POST /companies/entries Global Import Companies #
GET /companies/custom_fields Get Global Custom Fields #
POST /companies/custom_field Create Global Custom Field #
PUT /companies/custom_field Update Global Custom Field #
DELETE /companies/custom_field Delete Custom Field #
POST /companies/batchGet Batch Get Companies By Id Or Urn Using Post #
GET /companies/{id_or_urn} Get Company By Id Or Urn #
GET /companies/{id_or_urn}/employees Get Employees #
GET /companies/{id_or_urn}/userConnections Get User Connections #
POST /companies/attachments Batch Get Attachments #
DELETE /companies/attachments Batch Delete Attachments #
POST /companies/{id_or_urn}/attachments Batch Create Attachments #
PUT /companies/{id_or_urn}/attachments Batch Complete Upload #
GET /companies/{id_or_urn}/attachments/{urn} Get Attachment Content #
DELETE /companies/{id_or_urn}/attachments/{urn} Delete Attachment #
GET /watchlists/companies Get Company Watchlists By Owner #
POST /watchlists/companies Create Company Watchlist #
POST /watchlists/companies/{id_or_urn}/custom_field Create Company Watchlist Custom Field #
PUT /watchlists/companies/{id_or_urn}/custom_field Update Company Watchlist Custom Field #
DELETE /watchlists/companies/{id_or_urn}/custom_field Delete Company Watchlist Custom Field #
GET /watchlists/companies/{id_or_urn}/imports Get Company Watchlist Imports #
POST /watchlists/companies/{id_or_urn}/named_views Upsert Company Watchlist Named Views #
GET /watchlists/companies/{id_or_urn} Get Company Watchlist #
PUT /watchlists/companies/{id_or_urn} Update Company Watchlist #
DELETE /watchlists/companies/{id_or_urn} Delete Company Watchlist #
GET /watchlists/companies/{id_or_urn}/entries Get Company Watchlist Entries #
POST /watchlists/companies/{id_or_urn}/entries Company Watchlist Add Entries #
POST /watchlists/companies/{id_or_urn}:addCompanies Add Companies To Company Watchlist #
POST /watchlists/companies/{id_or_urn}:removeCompanies Remove Companies From Company Watchlist #
POST /watchlists/companies/{id_or_urn}/entries:batchDelete Company Watchlist Batch Delete Entries #
GET /watchlists/companies/imports/{id_or_urn} Get User Company Import #
GET /watchlists/companies/imports/{id_or_urn}/entries Get User Company Import Entries #
POST /search/companies_by_keywords Search Companies By Keywords #
GET /search/similar_companies/{id_or_urn} Search Similar Companies #
GET /search/typeahead Typeahead Search #
GET /search/search_agent Search Agent #

Documentation

Specifications

Other Resources

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OpenAPI Specification

harmonic-ai-companies-api-openapi.yml Raw ↑
openapi: 3.2.0
info:
  title: Harmonic.ai Public Companies API
  version: 0.0.1
  description: Public API documentation for Harmonic.ai.
tags:


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# Full source: https://raw.githubusercontent.com/api-evangelist/harmonic-ai/refs/heads/main/openapi/harmonic-ai-companies-api-openapi.yml