Formstack

Formstack is a no-code workplace productivity platform spanning online forms, document generation, electronic signature, and workflow automation. The developer portal at developers.formstack.com exposes a REST API (v2025.0) for forms, submissions, fields, webhooks, folders, and partial submissions, plus product-specific surfaces for Formstack Documents, Formstack Sign, and Formstack Workflows. Authentication uses OAuth 2.0. Machine-readable indexes and OpenAPI artifacts are surfaced at developers.formstack.com/llms.txt.

Formstack publishes 9 APIs on the APIs.io network, including Webhooks API, Confirmations API, Fields API, and 6 more. Tagged areas include Forms, Documents, E-Signature, Workflow-Automation, and No-Code.

Formstack’s developer surface includes authentication, documentation, changelog, GitHub presence, engineering blog, and 9 more developer resources.

🌐 Visit website 📡 Source on GitHub

26.6/100 thin ▬ flat Agent 29/100 agent ready Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0

AccessFreeSelf serve⚡ Free to try

1 APIs

Forms Documents E-Signature Workflow-Automation No-Code Authentication

Kin Score

Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0

Composite quality — 26.6/100 · thin

Contract Quality 2.8 / 23

Developer Ergonomics 4.3 / 18

Access Clarity 6.6 / 18

Operational Transparency 4.0 / 12

Contract Governance 0.0 / 11

Discoverability 6.8 / 9

Create-or-Update Ergonomics 0.0 / 10

Agent readiness — 29/100 · agent ready

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 6 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 6 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Create-or-Update Ergonomics applies to this provider. This API accepts writes, so it carries 10 points of the composite. It is scored from the published contracts themselves: whether a caller can create-or-update in one call, whether the write accepts a key the caller already holds, and whether the response says which branch ran. Without that, every write needs a search-and-branch in front of it, and the first time that check is skipped a duplicate record is created. Scored against the observed mean rather than raw — a provider at the catalog average is unchanged by this facet, not penalised by it.

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from github.com/api-evangelist/formstack: open an issue to ask a question, or submit a pull request to add artifacts. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

APIs 17

Individual APIs this provider publishes, each with its own machine-readable definition.

Formstack Forms API

REST API for creating, reading, updating, and deleting forms in a Formstack account, including form configuration, styling, and access rules.

Formstack Submissions API

Read, create, update, and delete form submissions; supports filtering by date, search, and field values. Returns submitted field data and metadata.

Formstack Fields API

Programmatically manage form fields - text, select, file upload, signature, payment, calculation, and others - including ordering, validation, and conditional logic.

Formstack Webhooks API

Configure webhook subscriptions to receive submission events at a customer-provided URL, with retry semantics for failed deliveries.

Formstack Folders API

Manage folder organization for forms within a Formstack account.

Formstack Documents API

Programmatic interface to Formstack Documents (formerly WebMerge) for generating PDFs, Word docs, and other templated documents from data payloads.

Formstack Sign API

Electronic signature API for sending documents for signature, tracking status, and retrieving signed copies. Part of the Formstack Suite.

Formstack Workflows API

Workflow automation surface for routing submissions, documents, and approvals across multi-step business processes.

Formstack OAuth 2.0

OAuth 2.0 authorization server used to authenticate API clients and issue access tokens for the Formstack REST API.

Formstack Confirmations API

The Confirmations API from Formstack — 2 operation(s) for confirmations.

Formstack Fields API

The Fields API from Formstack — 2 operation(s) for fields.

Formstack Folders API

The Folders API from Formstack — 2 operation(s) for folders.

Formstack Forms API

The Forms API from Formstack — 5 operation(s) for forms.

Formstack Notifications API

The Notifications API from Formstack — 2 operation(s) for notifications.

Formstack Subaccounts API

The Subaccounts API from Formstack — 1 operation(s) for subaccounts.

Formstack Submissions API

The Submissions API from Formstack — 2 operation(s) for submissions.

Formstack Webhooks API

The Webhooks API from Formstack — 2 operation(s) for webhooks.

Scroll for all 17

Open Collections 11

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

API Collection

OPEN COLLECTION

Formstack Webhooks

OPEN COLLECTION

Formstack Confirmations API

OPEN COLLECTION

Formstack Confirmations Fields API

OPEN COLLECTION

Formstack Confirmations Folders API

OPEN COLLECTION

Formstack Confirmations Forms API

OPEN COLLECTION

Formstack Confirmations Notifications API

OPEN COLLECTION

Formstack Confirmations Subaccounts API

OPEN COLLECTION

Formstack Confirmations Submissions API

OPEN COLLECTION

Formstack Confirmations Webhooks API

OPEN COLLECTION

Formstack API

OPEN COLLECTION

Scroll for all 11

Pricing Plans 1

Published pricing tiers and plan structures.

Formstack Plans Pricing

1 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Formstack Rate Limits

2 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals for API financial operations.

Formstack Finops

FINOPS

Security Posture 4

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Formstack Authentication

oauth2 · 1 scheme

SECURITY

Formstack Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Formstack Vulnerability Disclosure

disclosure policy published

SECURITY

Formstack Trust Center

SOC 2, ISO 27001, ISO 27017, ISO 27018, PCI DSS, HIPAA, FedRAMP, GDPR, CSA STAR

SECURITY

Scopes 1

OAuth scopes governing access to this provider's APIs.

Formstack Scopes

4 scopes · authorizationCode

4 scopes

SCOPES

Agentic Access 1

Recommended x-agentic-access execution contracts for AI agents.

Formstack Agentic Access

39 operations · 23 acting

AGENTIC

Resources

Documentation 1

Reference material describing how the API behaves

Documentation

Documentation

Agent Surfaces 2

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

LlmsText

LlmsText

Build 1

SDKs, sample code, and the tooling you integrate with

GitHub

GitHub

Access & Security 5

Authentication, authorization, and security posture

TrustCenter

TrustCenter

VulnerabilityDisclosure

VulnerabilityDisclosure

DomainSecurity

DomainSecurity

Authentication

Authentication

OAuthScopes

OAuthScopes

Operate 1

Status, limits, changes, and where to get help

ChangeLog

ChangeLog

Company 4

The organization behind the API

Website

Website

LinkedIn

Twitter

Twitter

Blog

Blog

Source (apis.yml)

aid: formstack
url: https://raw.githubusercontent.com/api-evangelist/formstack/refs/heads/main/apis.yml
name: Formstack
kind: company
description: Formstack is a no-code workplace productivity platform spanning online forms, document generation, electronic
  signature, and workflow automation. The developer portal at developers.formstack.com exposes a REST API (v2025.0) for forms,
  submissions, fields, webhooks, folders, and partial submissions, plus product-specific surfaces for Formstack Documents,
  Formstack Sign, and Formstack Workflows. Authentication uses OAuth 2.0. Machine-readable indexes and OpenAPI artifacts are
  surfaced at developers.formstack.com/llms.txt.
deliveryModel:
  model: unknown
  open_source: false
  commercial: false
  callable_host: true
  label: Delivery model not determined — needs a product licence on record
  confidence: low
  source:
  - openapi
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: free
  onboarding: self-serve
  trial: false
  try_now: true
  public: false
  label: Free · Self-serve signup
  confidence: high
  source:
  - plans
  - authentication
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/formstack.png
tags:
- Forms
- Documents
- E-Signature
- Workflow-Automation
- No-Code
- Authentication
tags_raw:
- Forms
- Documents
- eSignature
- Workflow Automation
- No-Code
- OAuth2
created: '2026-05-23'
modified: '2026-05-30'
specificationVersion: '0.23'
apis:
- aid: formstack:forms
  name: Formstack Forms API
  description: REST API for creating, reading, updating, and deleting forms in a Formstack account, including form configuration,
    styling, and access rules.
  humanURL: https://developers.formstack.com/reference/api-overview
  baseURL: https://www.formstack.com/api/v2
  tags:
  - Forms
  - REST
  properties:
  - type: Documentation
    url: https://developers.formstack.com/reference/api-overview
- aid: formstack:submissions
  name: Formstack Submissions API
  description: Read, create, update, and delete form submissions; supports filtering by date, search, and field values. Returns
    submitted field data and metadata.
  humanURL: https://developers.formstack.com/reference/api-overview
  baseURL: https://www.formstack.com/api/v2
  tags:
  - Submissions
  - Data
  properties:
  - type: Documentation
    url: https://developers.formstack.com/reference/api-overview
- aid: formstack:fields
  name: Formstack Fields API
  description: Programmatically manage form fields - text, select, file upload, signature, payment, calculation, and others
    - including ordering, validation, and conditional logic.
  humanURL: https://developers.formstack.com/reference/api-overview
  baseURL: https://www.formstack.com/api/v2
  tags:
  - Fields
  - Form Schema
  properties:
  - type: Documentation
    url: https://developers.formstack.com/reference/api-overview
- aid: formstack:webhooks
  name: Formstack Webhooks API
  description: Configure webhook subscriptions to receive submission events at a customer-provided URL, with retry semantics
    for failed deliveries.
  humanURL: https://developers.formstack.com/reference/api-overview
  baseURL: https://www.formstack.com/api/v2
  tags:
  - Webhook
  - Event
  tags_raw:
  - Webhooks
  - Events
  properties:
  - type: Documentation
    url: https://developers.formstack.com/reference/api-overview
  - type: AsyncAPI
    url: https://raw.githubusercontent.com/api-evangelist/formstack/refs/heads/main/openapi/formstack-asyncapi.yml
- aid: formstack:folders
  name: Formstack Folders API
  description: Manage folder organization for forms within a Formstack account.
  humanURL: https://developers.formstack.com/reference/api-overview
  baseURL: https://www.formstack.com/api/v2
  tags:
  - Folders
  - Organization
  properties:
  - type: Documentation
    url: https://developers.formstack.com/reference/api-overview
- aid: formstack:documents
  name: Formstack Documents API
  description: Programmatic interface to Formstack Documents (formerly WebMerge) for generating PDFs, Word docs, and other
    templated documents from data payloads.
  humanURL: https://developers.formstack.com/
  baseURL: https://www.webmerge.me/api
  tags:
  - Documents
  - Document Generation
  - PDF
  properties:
  - type: Documentation
    url: https://developers.formstack.com/
- aid: formstack:sign
  name: Formstack Sign API
  description: Electronic signature API for sending documents for signature, tracking status, and retrieving signed copies.
    Part of the Formstack Suite.
  humanURL: https://developers.formstack.com/
  baseURL: https://www.formstack.com/api/v2
  tags:
  - E-Signature
  - Sign
  tags_raw:
  - eSignature
  - Sign
  properties:
  - type: Documentation
    url: https://developers.formstack.com/
- aid: formstack:workflows
  name: Formstack Workflows API
  description: Workflow automation surface for routing submissions, documents, and approvals across multi-step business processes.
  humanURL: https://developers.formstack.com/
  baseURL: https://www.formstack.com/api/v2
  tags:
  - Workflows
  - Automation
  properties:
  - type: Documentation
    url: https://developers.formstack.com/
- aid: formstack:oauth2
  name: Formstack OAuth 2.0
  description: OAuth 2.0 authorization server used to authenticate API clients and issue access tokens for the Formstack REST
    API.
  humanURL: https://developers.formstack.com/reference/oauth2-authentication
  baseURL: https://www.formstack.com/api/v2/oauth2
  tags:
  - Authentication
  tags_raw:
  - OAuth2
  - Authentication
  properties:
  - type: Documentation
    url: https://developers.formstack.com/reference/oauth2-authentication
- aid: formstack:formstack-confirmations-api
  name: Formstack Confirmations API
  description: The Confirmations API from Formstack — 2 operation(s) for confirmations.
  humanURL: https://developers.formstack.com/reference/api-overview
  baseURL: https://www.formstack.com/api/v2
  tags:
  - Confirmations
  properties:
  - type: OpenAPI
    url: openapi/formstack-confirmations-api-openapi.yml
- aid: formstack:formstack-fields-api
  name: Formstack Fields API
  description: The Fields API from Formstack — 2 operation(s) for fields.
  humanURL: https://developers.formstack.com/reference/api-overview
  baseURL: https://www.formstack.com/api/v2
  tags:
  - Fields
  properties:
  - type: OpenAPI
    url: openapi/formstack-fields-api-openapi.yml
- aid: formstack:formstack-folders-api
  name: Formstack Folders API
  description: The Folders API from Formstack — 2 operation(s) for folders.
  humanURL: https://developers.formstack.com/reference/api-overview
  baseURL: https://www.formstack.com/api/v2
  tags:
  - Folders
  properties:
  - type: OpenAPI
    url: openapi/formstack-folders-api-openapi.yml
- aid: formstack:formstack-forms-api
  name: Formstack Forms API
  description: The Forms API from Formstack — 5 operation(s) for forms.
  humanURL: https://developers.formstack.com/reference/api-overview
  baseURL: https://www.formstack.com/api/v2
  tags:
  - Forms
  properties:
  - type: OpenAPI
    url: openapi/formstack-forms-api-openapi.yml
- aid: formstack:formstack-notifications-api
  name: Formstack Notifications API
  description: The Notifications API from Formstack — 2 operation(s) for notifications.
  humanURL: https://developers.formstack.com/reference/api-overview
  baseURL: https://www.formstack.com/api/v2
  tags:
  - Notification
  tags_raw:
  - Notifications
  properties:
  - type: OpenAPI
    url: openapi/formstack-notifications-api-openapi.yml
- aid: formstack:formstack-subaccounts-api
  name: Formstack Subaccounts API
  description: The Subaccounts API from Formstack — 1 operation(s) for subaccounts.
  humanURL: https://developers.formstack.com/reference/api-overview
  baseURL: https://www.formstack.com/api/v2
  tags:
  - Subaccounts
  properties:
  - type: OpenAPI
    url: openapi/formstack-subaccounts-api-openapi.yml
- aid: formstack:formstack-submissions-api
  name: Formstack Submissions API
  description: The Submissions API from Formstack — 2 operation(s) for submissions.
  humanURL: https://developers.formstack.com/reference/api-overview
  baseURL: https://www.formstack.com/api/v2
  tags:
  - Submissions
  properties:
  - type: OpenAPI
    url: openapi/formstack-submissions-api-openapi.yml
- aid: formstack:formstack-webhooks-api
  name: Formstack Webhooks API
  description: The Webhooks API from Formstack — 2 operation(s) for webhooks.
  humanURL: https://developers.formstack.com/reference/api-overview
  baseURL: https://www.formstack.com/api/v2
  tags:
  - Webhook
  tags_raw:
  - Webhooks
  properties:
  - type: OpenAPI
    url: openapi/formstack-webhooks-api-openapi.yml
common:
- type: AgenticAccess
  url: agentic-access/formstack-agentic-access.yml
- type: TrustCenter
  url: security/formstack-trust-center.yml
- type: VulnerabilityDisclosure
  url: security/formstack-vulnerability-disclosure.yml
- type: DomainSecurity
  url: security/formstack-domain-security.yml
- type: Authentication
  url: authentication/formstack-authentication.yml
- type: OAuthScopes
  url: scopes/formstack-scopes.yml
- type: Website
  url: https://www.formstack.com/
- type: Documentation
  url: https://developers.formstack.com/
- type: ChangeLog
  url: https://developers.formstack.com/changelog
- type: LlmsText
  url: https://developers.formstack.com/llms.txt
- type: LinkedIn
  url: https://www.linkedin.com/company/formstack
- type: GitHub
  url: https://github.com/formstack
- type: Twitter
  url: https://twitter.com/Formstack
- url: https://www.formstack.com/blog/rss.xml
  type: Blog
integrations:
- name: Salesforce
- name: HubSpot
- name: Microsoft Dynamics 365
- name: Google Workspace
- name: Slack
- name: Stripe
- name: PayPal
- name: Zapier
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

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