ChangeGraph API

Monitor companies, products and websites and emit evidence-backed pricing, hiring, product, technology, executive and expansion events.

• Product and pricing
• Developer documentation
• Create a free account
• OpenAPI contract
• Postman collection

Quickstart: see a detected change without an account

This public demo runs the production detection engine without storing or metering the payload.

curl -sS -X POST https://changegraph-api.com/v1/demo/detect \
  -H 'content-type: application/json' \
  -d '{"subject":"Acme Corp","before":{"plan.pro.monthly":"49","headcount.engineering":"120"},"after":{"plan.pro.monthly":"59","headcount.engineering":"145"}}'

A successful response has eventCount: 2. Each item in events identifies the change kind, direction, before/after values, confidence and supporting evidence:

{
  "subject": "Acme Corp",
  "eventCount": 2,
  "events": [
    {
      "kind": "hiring",
      "direction": "increased",
      "factKey": "headcount.engineering",
      "before": "120",
      "after": "145",
      "confidence": 80,
      "evidence": [
        {"source": "demo://before", "observedAt": "2026-09-06T00:00:00.000Z", "factKey": "headcount.engineering", "before": "120", "after": null},
        {"source": "demo://before", "observedAt": "2026-09-06T00:00:00.000Z", "factKey": "headcount.engineering", "before": null, "after": "145"}
      ]
    },
    {
      "kind": "pricing",
      "direction": "increased",
      "factKey": "plan.pro.monthly",
      "before": "49",
      "after": "59",
      "confidence": 80,
      "evidence": [
        {"source": "demo://before", "observedAt": "2026-09-06T00:00:00.000Z", "factKey": "plan.pro.monthly", "before": "49", "after": null},
        {"source": "demo://before", "observedAt": "2026-09-06T00:00:00.000Z", "factKey": "plan.pro.monthly", "before": null, "after": "59"}
      ]
    }
  ],
  "requestId": "req_example"
}

That is the first useful result: a normalized event that an alert, CRM or research workflow can act on. Each safe synthetic evidence row shows the before/after observation supporting the event; the demo:// sources make clear that these are demonstration records rather than customer evidence.

Create and use a free API key

Request the verification email. This attribution tuple identifies this README.

curl -sS -X POST https://changegraph-api.com/v1/keys \
  -H 'content-type: application/json' \
  -d '{"email":"you@example.com","source":{"source":"github","medium":"developer","campaign":"changegraph-github","content":"readme"}}'

Copy the one-time token from the email, exchange it, and copy the returned apiKey immediately. The key is shown only once.

curl -sS -X POST https://changegraph-api.com/v1/keys/claim \
  -H 'content-type: application/json' \
  -d '{"token":"PASTE_ONE_TIME_TOKEN_FROM_EMAIL"}'

export KEY='PASTE_API_KEY_FROM_CLAIM_RESPONSE'

Create a monitor and capture its real ID, establish a baseline, then submit a changed observation. Python is used only to read the id from the JSON reply.

MONITOR_ID="$(curl -sS -X POST https://changegraph-api.com/v1/monitors \
  -H "Authorization: Bearer $KEY" \
  -H 'content-type: application/json' \
  -d '{"subject":"Acme Corp","kinds":["pricing","hiring","executive"]}' \
  | python3 -c 'import json,sys; print(json.load(sys.stdin)["id"])')"

curl -sS -X POST "https://changegraph-api.com/v1/monitors/$MONITOR_ID/snapshots" \
  -H "Authorization: Bearer $KEY" \
  -H 'content-type: application/json' \
  -d '{"source":"https://acme.example/pricing","facts":{"plan.pro.monthly":"49","headcount.engineering":"120"}}'

curl -sS -X POST "https://changegraph-api.com/v1/monitors/$MONITOR_ID/snapshots" \
  -H "Authorization: Bearer $KEY" \
  -H 'content-type: application/json' \
  -d '{"source":"https://acme.example/pricing","facts":{"plan.pro.monthly":"59","headcount.engineering":"145"}}'

The first snapshot returns baseline: true; the second returns baseline: false, eventCount: 2, and the detected events.

SDKs

• Python SDK — reads CHANGEGRAPH_API_KEY
• TypeScript SDK

Copy the file you need into your project. The OpenAPI document remains the authoritative operation and schema contract.

Collection scope

The runnable Postman collection includes the public demo, the no-key checkout path, key bootstrap, and API-key product operations. It intentionally excludes the provider-only billing webhook and browser-session subscription, invoice, and payment routes: those require a signed hub request or the dashboard's HttpOnly session and CSRF controls, and a bearer API key cannot run them. The OpenAPI document linked above remains the reference for those operations.

Authentication and troubleshooting

API operations accept Authorization: Bearer <API_KEY> (or x-api-key where documented). Public demo and health operations require no credential.

• 401: set KEY to the API key returned by /v1/keys/claim; request a new key if it was revoked.
• 400 invalid_request: make both before and after non-empty string maps. A client-side schema tool may label the same input problem 422 before send.
• 429: wait for Retry-After when present, then retry with backoff.

Errors use a stable error.code and a request ID. Include that request ID when asking for support; never include the API key or claim token.

Distribution attribution

The key request above uses the stable tuple github / developer / changegraph-github / readme. The Postman collection and SDKs carry their own source metadata. Attribution compares qualified activation and retained use; it does not claim that this channel already performs.

License

MIT