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Kit

Kit API

Yes. Kit publishes a public REST API. See developers.kit.com for the full reference.

WebhooksMCP also availableLLMs: Claude (Desktop/Web), ChatGPT, Claude Code, Cursor, Windsurf, Cline, Gemini
Open API docsTry Kit
Public REST API documentedAgent-readiness 7/10
Facts verified 2026-07-13

What is the Kit API?

Kit has a documented public REST API (v4) at developers.kit.com covering subscribers, broadcasts, sequences, tags, segments, custom fields and webhooks, with bulk endpoints for async batch work. Auth supports OAuth apps and personal API keys.

For agents there is a genuinely useful extra: the docs are published as agent-readable markdown via llms.txt, so a coding agent can read the entire API reference without scraping. Webhooks cover subscriber and broadcast events for event-driven flows.

The gaps are a missing public OpenAPI spec and no official SDKs, so you generate clients by hand or hit the endpoints directly. For LLM-in-the-loop work the MCP server is less code; the API wins for scheduled jobs and dashboards.

For the broader picture: Kit review, full pricing breakdown, .

HOOK IT TO YOUR STACK

Real Kit API calls you'll write

kit-apirest
#Pull the latest data from Kit
GET/v1/records?limit=10&sort=-created_at
200 OK · 10 records
Most recent entry2 min ago
Records this week147
API calls today1,832
Rate limit remaining8,168 / 10k
Schedule via cron, pipe results.
kit-apirest
#Push a new record with custom metadata
POST/v1/records
201 Created · record_id: r_5a7
Validationpassed
Webhooks triggered2
Stored size1.2 KB
kit-apirest
#Subscribe to webhook events
POST/v1/webhooks
201 Created · webhook_id: wh_3f
Signing secretwhsec_••••
Eventsrecord.created
Statusactive
TMB SCORE FOR KitAgent fit: 7/10
Read review →

Endpoints illustrative. Confirm exact paths against the live API docs before integrating.

Pricing, limits, and integration

The API comes with your Kit account with no separate fee. The MCP server needs a paid plan (Creator or Creator Pro) and is limited to 120 requests per minute per token; write operations prompt for confirmation in the client before executing.

For agent builds, budget around the rate limit rather than credits: unlike metered data APIs there is no per-call cost, so continuous automation is economical once you are on a paid plan.

How much does the Kit API actually cost?

Verify on docs

Kit publishes an API, but per-tier gating wasn't extracted automatically.

  • Most likely scenario: API access is either included in all paid plans, or it's gated to higher tiers and we need to verify on the live docs page.
  • Until verified, treat the question "which plan unlocks the API" as open. Don't budget on the assumption it's free with the cheapest paid plan.

API at a glance

Auth method
—
SDK languages
—
OpenAPI spec
—
Webhooks
available
Structured outputs
—

Which AI clients can read Kit data?

Not every AI assistant supports MCP natively. Here's the per-client picture for Kit specifically.

ClientSupportNotes
Claude (Desktop/Web)Native MCPAdd app.kit.com/mcp as a custom connector; OAuth sign-in to your Kit account, no API key needed.
ChatGPTNative MCPExplicitly supported by Kit's official MCP docs; connect via the same OAuth flow.
Claude CodeNative MCPclaude mcp add --transport http kit https://app.kit.com/mcp. The separate Developer Docs MCP (developers.kit.com/mcp) is built for coding agents.
CursorNative MCPOfficial Kit setup guide at developers.kit.com/mcp; add app.kit.com/mcp as an MCP server, OAuth sign-in to your Kit account, no API key.
WindsurfNative MCPCovered by Kit's official MCP setup guides; connect app.kit.com/mcp via the OAuth flow.
ClineNative MCPCovered by Kit's official MCP setup guides; connect app.kit.com/mcp via the OAuth flow.
GeminiNative MCPListed as a supported client on kit.com/ai/mcp; connect via the same OAuth flow, no API key needed.

Kit also has an MCP server

If you're wiring Kit into Claude / Cursor / Codex, the MCP server is usually less code than the REST API.

See Kit MCP page

What you can build with the Kit API

Three personas, three different shapes of build. Pick the row that matches how you actually ship.

SOLO DEV / FOUNDER

Glue Kit into your daily workflow

  • Pull a digest of fresh activity into your morning Slack
  • Trigger a one-off backfill when something looks off
  • Pipe data into your own SQLite for ad-hoc queries
Effort: A weekend, one Node or Python script
AGENCY / CONSULTANT

Sell Kit reporting at scale

  • White-label Kit data into client-branded dashboards
  • Run scheduled multi-account reports without logging into the Kit UI
  • Cross-reference with the rest of the client's stack (CRM, analytics, ad spend)
Effort: 1-2 weeks, hits multi-tenant auth quickly
IN-HOUSE ENGINEER

Production pipelines for Kit

  • Real-time sync into your warehouse via webhooks
  • Custom alerts the dashboard's built-in alerting can't express
  • Backfill + idempotency handling for Kit data older than the dashboard exposes
Effort: Multi-week project, expect rate-limit tuning

Quickstart template

# Starter template — endpoint paths and SDK package names come from
# the Kit API docs: https://developers.kit.com

curl -X GET "https://developers.kit.com/<your-endpoint>" \
  -H "Authorization: Bearer $TOKEN" \
  -H "Accept: application/json" | jq .

Template only. Endpoint paths, exact base URL, and auth header format come from developers.kit.com.

Limits and gotchas

  • No OpenAPI spec — you write typed clients by hand or use a third-party generator on the docs HTML.
  • Webhooks available — react to Kit events in real time instead of polling.
  • No official SDK detected. Plan on hitting the API directly with your HTTP client of choice.
  • Rate limits: always read the docs page before scaling — the published limit is usually lower than the practical one and overages can be expensive.
  • No-code fallback: Zapier and Make.com cover the common triggers if you want to skip writing API code for simple flows.
7/10

Agent-readiness verdict

A clean, well-documented v4 REST API with OAuth and API-key auth, webhooks, bulk endpoints and agent-readable llms.txt docs. It scores a 7 out of 10: everything an integration needs is there, but no public OpenAPI spec and no official SDKs means more hand-rolled client code than the best-in-class APIs.

Official MCP at app.kit.com/mcp verified 2026-07-07: OAuth, full v4 surface incl. writes w/ safety annotations, ChatGPT+Claude+Cursor, paid plans, 120rpm. Second Developer Docs MCP at developers.kit.com/mcp. llms.txt live. Score 7->8 (Joonas approved).

Kit API FAQ

Does Kit have a public API?+
Yes — REST API at developers.kit.com.
Does Kit support webhooks?+
Yes — webhooks are available on standard plans.
Should I use the API or the MCP server for Claude / Cursor / Codex?+
Prefer the MCP server for agent workflows — it's less code and pre-handles auth flows. Use the REST API for scheduled jobs, dashboards, and anything outside an LLM-driven flow.

Sources

Joonas Rotko
Joonas RotkoAuthor & Founder of That Marketing Buddy

10+ years in digital marketing. I review marketing software for AI-stack fit: real pricing, MCP and API support, and how cleanly each tool drops into an AI agent workflow, cross-checked against verified data and real user feedback.

About meHow I review

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