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FormBuilderAPI

A small, boring REST API for getting your data out and reacting to new responses. Scoped API keys, JSON everywhere, no SDK required. Included on every plan.

Create an API keyJump to endpoints

Quick start

# 1. Settings → API & Zapier → Create API key
# 2. Call the API
curl https://api.formbuilder.com/api/v1/forms \
  -H "Authorization: Bearer fbpat_…"

# 3. Get pinged on every new response
curl -X POST https://api.formbuilder.com/api/v1/hooks \
  -H "Authorization: Bearer fbpat_…" \
  -H "Content-Type: application/json" \
  -d '{"target_url":"https://example.com/hook"}'

Authentication

Send your key as Authorization: Bearer <key>. Keys are created in Settings → API & Zapier, shown once, and can be revoked any time. Revoking a key deletes its hooks.

Scopes

forms:read, forms:write, responses:read, hooks:manage. A missing scope returns 403. Errors are JSON: { "error": "…" }.

Webhook payloads

Hooks POST JSON: event, response_id, form_id, form_title, submitted_at, country_code, fields (label → value) and data (field id → value). Respond 2xx; a 410 unsubscribes the hook. Held (over-limit) responses are never sent.

MCP server

Use FormBuilder from Claude, ChatGPT, Cursor or any MCP client

FormBuilder ships a remote MCP server (Streamable HTTP, OAuth 2.1) at https://api.formbuilder.com/mcp. Tools: formbuilder_signup, formbuilder_create_form, formbuilder_list_forms, formbuilder_get_form_fields, formbuilder_list_responses, formbuilder_create_webhook. Connecting opens a normal “Allow” screen and creates a 30-day API key you can revoke under Settings → API keys. Headless agents with no browser can use https://api.formbuilder.com/mcp/open: call formbuilder_signup and the new key is remembered for the session.

claude.ai · Claude Desktop · ChatGPT

Add a custom connector / app with the URL https://api.formbuilder.com/mcp. You’ll be asked to sign in and click Allow. Then: “Make me a customer feedback form and publish it.”

Claude Code · Gemini CLI

claude mcp add --transport http formbuilder \
  https://api.formbuilder.com/mcp

# or the plugin (skill + MCP):
claude plugin marketplace add bluetickventures/fb
claude plugin install formbuilder@formbuilder

gemini mcp add formbuilder https://api.formbuilder.com/mcp

Cursor · Windsurf · other stdio clients

{
  "mcpServers": {
    "formbuilder": {
      "command": "npx",
      "args": ["-y", "formbuilder-mcp"],
      "env": { "FORMBUILDER_API_KEY": "fbpat_…" }
    }
  }
}

Omit the key to use /mcp/open and sign up from inside the conversation.

OAuth discovery: /.well-known/oauth-authorization-server and /.well-known/oauth-protected-resource on api.formbuilder.com (dynamic client registration, PKCE S256, refresh tokens). Agent Skill for Claude: skills/formbuilder-forms.

Endpoints

Base URL https://api.formbuilder.com/api/v1. All responses are application/json.

POST/signupscope none (public)

Create a free account and get an API key in one call — built for AI agents and scripts. No browser or captcha. The email owner gets a claim link; until they claim, the account works like an unclaimed publish (response cap applies). Rate limit 3/hour per IP; 409 if the email already has an account.

ParamInDescription
email
string
bodyOwner email (required)
name
string
bodyOptional display name
agent
string
bodyOptional — name of the agent/tool creating the account, e.g. "claude-code"

Request

curl -X POST https://api.formbuilder.com/api/v1/signup \
  -H "Content-Type: application/json" \
  -d '{ "email": "[email protected]", "agent": "claude-code" }'

Response

201 { "user_id": "usr_…", "email": "[email protected]", "api_key": "fbpat_…",
  "abilities": ["forms:read","forms:write","responses:read","hooks:manage"],
  "verify_required": true,
  "next": { "create_form": "POST https://api.formbuilder.com/api/v1/forms", "docs": "https://formbuilder.com/developers", "openapi": "https://formbuilder.com/openapi.json" } }
POST/formsscope forms:write

Create a form from JSON, optionally publishing it in the same call. Published forms go through the same safety review as the app; if held, `publish_blocked_reasons` says why. Free plan: 5 forms.

ParamInDescription
title
string
bodyForm title (required)
fields
array
bodyAt least one { label, type, required?, placeholder?, options?, page? }. Types: text, email, textarea, select, radio, checkbox, number, date, phone, url, file, rating, signature, nps, matrix, ranking, score, calculation, payment
publish
boolean
bodyPublish immediately (default false)
description
string
bodyOptional

Request

curl -X POST https://api.formbuilder.com/api/v1/forms \
  -H "Authorization: Bearer fbpat_…" -H "Content-Type: application/json" \
  -d '{ "title": "Contact us", "publish": true,
        "fields": [ { "label": "Name", "type": "text", "required": true },
                    { "label": "Email", "type": "email", "required": true },
                    { "label": "Message", "type": "textarea" } ] }'

Response

201 { "id": "frm_…", "title": "Contact us", "slug": "contact-us", "status": "published",
  "public_url": "https://forms.formbuilder.com/f/contact-us", "edit_url": "https://formbuilder.com/forms/frm_…/edit",
  "publish_blocked_reasons": null, "fields": 3 }
GET/mescope forms:read

Identify the account behind the API key. Useful as an auth test.

Request

curl https://api.formbuilder.com/api/v1/me \
  -H "Authorization: Bearer fbpat_…"

Response

{ "id": "usr_…", "email": "[email protected]", "name": "Jordan", "plan": "pro" }
GET/formsscope forms:read

List your forms, newest first.

ParamInDescription
page
integer
queryPage number, default 1
limit
integer
queryPer page, 1–100, default 50

Request

curl "https://api.formbuilder.com/api/v1/forms?limit=20" \
  -H "Authorization: Bearer fbpat_…"

Response

{
  "data": [
    { "id": "frm_…", "title": "Contact form", "slug": "contact", "status": "published",
      "is_public": true, "response_count": 128, "view_count": 2044,
      "created_at": "2026-07-01T12:00:00.000Z", "updated_at": "2026-08-10T09:30:00.000Z" }
  ],
  "pagination": { "page": 1, "limit": 20, "total": 3 }
}
GET/forms/{formId}/fieldsscope forms:read

Field schema for a form — ids, labels, types, required flags and options. Use this to map fields by id.

ParamInDescription
formId
string
pathForm id

Request

curl https://api.formbuilder.com/api/v1/forms/frm_123/fields \
  -H "Authorization: Bearer fbpat_…"

Response

{
  "form": { "id": "frm_123", "title": "Contact form" },
  "data": [
    { "id": "fld_a1", "label": "Full name", "type": "text", "required": true, "options": null },
    { "id": "fld_b2", "label": "Topic", "type": "select", "required": false, "options": ["Sales", "Support"] }
  ]
}
GET/forms/{formId}/responsesscope responses:read

Responses for a form, newest first. Response `data` is keyed by field id. Responses held over a free-plan limit return `locked: true` with empty data until the account upgrades.

ParamInDescription
formId
string
pathForm id
page
integer
queryPage number, default 1
limit
integer
queryPer page, 1–100, default 50

Request

curl "https://api.formbuilder.com/api/v1/forms/frm_123/responses?limit=50" \
  -H "Authorization: Bearer fbpat_…"

Response

{
  "form": { "id": "frm_123", "title": "Contact form" },
  "data": [
    { "id": "rsp_…", "form_id": "frm_123", "submitted_at": "2026-08-16T18:02:11.000Z",
      "data": { "fld_a1": "Jordan Meyer", "fld_b2": "Sales" },
      "metadata": { "payment_status": "paid" }, "is_test": false }
  ],
  "pagination": { "page": 1, "limit": 50, "total": 128 }
}
POST/hooksscope hooks:manage

Subscribe an HTTPS URL to `response.created`. FormBuilder POSTs each new response there within seconds (REST hooks — the same mechanism the Zapier app uses). Max 100 hooks per account; a `410 Gone` from your endpoint auto-deletes the hook.

ParamInDescription
target_url
string
bodyHTTPS URL to receive POSTs (no private addresses)
event
string
bodyOnly `response.created` today (default)
form_id
string
bodyOptional — omit to receive responses from all your forms

Request

curl -X POST https://api.formbuilder.com/api/v1/hooks \
  -H "Authorization: Bearer fbpat_…" -H "Content-Type: application/json" \
  -d '{ "target_url": "https://example.com/hooks/formbuilder", "form_id": "frm_123" }'

Response

201 { "id": "hk_…", "event": "response.created", "form_id": "frm_123", "target_url": "https://example.com/hooks/formbuilder" }
DELETE/hooks/{hookId}scope hooks:manage

Unsubscribe a hook.

ParamInDescription
hookId
string
pathHook id returned on subscribe

Request

curl -X DELETE https://api.formbuilder.com/api/v1/hooks/hk_123 \
  -H "Authorization: Bearer fbpat_…"

Response

{ "message": "Hook deleted" }

Limits & conventions

  • Pagination is page/limit; limit is capped at 100.
  • Timestamps are ISO-8601 UTC strings.
  • Up to 100 hooks per account. Delivery is fire-and-forget per response (no automatic retry today) — make your endpoint idempotent and fast, and use /responses to backfill if you miss one.
  • Machine-readable spec: /openapi.json (OpenAPI 3.1). Site summary for LLM agents: /llms.txt.
  • Need more write endpoints (update forms, submit responses server-to-server)? Tell us what you're building — it shapes what ships next.

Prefer no code? Use Zapier.

The same hooks power the FormBuilder Zapier app — 6,000+ destinations, no endpoint to host.

See Zapier integrations

Help & support

Help CenterSystem status[email protected]

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