Sync GTM REST API

The REST API puts Sync GTM’s waterfall enrichment behind a plain HTTPS endpoint, so your own backend, CRM sync or data pipeline can look up contact data without a table and without an AI client.

It runs the same lookups as the MCP tools — same inputs, same providers, same credit prices — and bills the same organization balance. The difference is who is calling: the MCP server is for an assistant you talk to, the API is for code you write.

Base URL: https://api.syncgtm.com/v1/api
Authentication: Bearer API key (sgtm_live_…)
Format: JSON in, JSON out
Rate limit: 60 requests per minute per key

Quickstart

Create an API key

In the app, open Settings → API keys and click Create key. Only organization owners and admins can create keys. Copy the key when it is shown — it is displayed once and cannot be retrieved again. See Authentication.

Make your first call


curl https://api.syncgtm.com/v1/api/enrich/work-email \
  -H "Authorization: Bearer $SYNCGTM_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"linkedin_url": "https://www.linkedin.com/in/janedoe"}'

Read the response


{
  "status": "found",
  "data": { "email": "jane@stripe.com" }
}

A miss is still a 200, with "status": "not_found" and "data": null — and it costs nothing.

Endpoints

Every endpoint is a POST with a JSON body. Full request and response details are on each page.

Endpoint	Cost	What it does
`POST /enrich/work-email`	1 credit per email found	LinkedIn URL, or name + company domain → work email
`POST /enrich/personal-email`	3 credits per email found	LinkedIn URL → personal mailbox address
`POST /enrich/mobile`	10 credits per number found	LinkedIn URL → mobile phone number
`POST /enrich/verify-email`	0.2 credits per verdict	Email → `Verified` or `Unverified`

See the endpoint reference for the shared request and response shapes.

How it behaves

Waterfall enrichment. Each lookup tries several data providers in sequence and stops at the first one that answers. You are charged once per lookup, never once per provider tried.
You pay for answers, not attempts. A not_found result is free. A request that times out or fails on our side is refunded.
Stable response bodies. Success is always { status, data }; failure is always { error: { code, message } }. Provider names are never part of the response. See Errors.
Safe retries. Send an Idempotency-Key header and a retried request replays the first response for 24 hours instead of charging again. See Rate limits and retries.
One balance. API calls draw on your organization’s credits, the same pool the app and the MCP server use. Check it on the usage and billing page.

API or MCP?

Use the	When
REST API	A program is making the call — a nightly CRM sync, a signup webhook, a script over a CSV. You want fixed JSON and HTTP status codes.
MCP server	A person is asking — in Claude, ChatGPT or Cursor. You want 50+ tools, chained by the assistant, with browser sign-in and no key to store.

The API covers the four highest-volume contact lookups today. Everything else — company enrichment, people search, signals — is available through the MCP server and in tables.

Support

Join the Sync GTM Slack Community
Contact support through the chat widget on docs.syncgtm.com

Include the endpoint, the HTTP status and the error.code when you report a problem — never the full API key.