Dropbox Sign (HelloSign) website screenshot

Dropbox Sign (HelloSign)

Dropbox Sign (formerly HelloSign) is an eSignature platform whose v3 REST API lets developers send documents for legally binding electronic signature, build reusable templates, embed signing directly in their own apps, run bulk send jobs, and manage accounts, teams, and API apps. The API exposes 73 operations across 12 product areas (Signature Request, Template, Bulk Send, Embedded, Account, Team, Report, Fax, Fax Line, Unclaimed Draft, API App, OAuth), with API-key and OAuth 2.0 authentication, 23 webhook event types, official SDKs in six languages, and a published hosted documentation MCP server. HelloSign was a Y Combinator company (S11), acquired by Dropbox in 2019 and rebranded to Dropbox Sign in 2022; the API base host remains api.hellosign.com.

Dropbox Sign (HelloSign) publishes 12 APIs on the APIs.io network, including Account API, Api App API, Bulk Send Job API, and 9 more. Tagged areas include Company, eSignature, Electronic Signatures, Documents, and Digital Agreements.

The Dropbox Sign (HelloSign) catalog on APIs.io includes 1 event-driven AsyncAPI specification.

Dropbox Sign (HelloSign)’s developer surface includes authentication, sandbox, changelog, documentation, API reference, getting-started guide, support, and 27 more developer resources.

🌐 Visit website 📡 Source on GitHub
62.8/100 strong ▬ flat Agent 71/100 agent native Full breakdown ↓
scored 2026-07-27 · rubric v0.5
AccessSelf serve
12 APIs 1 MCP Servers
CompanyeSignatureElectronic SignaturesDocumentsDigital AgreementsSignature WorkflowEmbedded SigningCompliance

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-07-27 · rubric v0.5
Composite quality — 62.8/100 · strong
Contract Quality 16.8 / 25
Developer Ergonomics 15.7 / 20
Commercial Clarity 12.1 / 20
Operational Transparency 8.2 / 13
Governance 0.0 / 12
Discoverability 10.0 / 10
Agent readiness — 71/100 · agent native
Machine-Readable Contract 18 / 18
Agentic Access Contract 15 / 15
MCP Server 12 / 12
Machine-Readable Auth 10 / 10
Idempotency 0 / 9
Stable Error Semantics 8 / 8
Request/Response Examples 0 / 7
Rate-Limit Signaling 0 / 7
Typed Event Surface 6 / 6
Agent Skills 5 / 5
Well-Known Catalog 0 / 4
Consent & Bot Identity 0 / 3
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/hellosign: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 12

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

Dropbox Sign (HelloSign) Account API

{'$ref': './markdown/en/tags/account-tag-description.md'}

Dropbox Sign (HelloSign) Api App API

{'$ref': './markdown/en/tags/api-app-tag-description.md'}

Dropbox Sign (HelloSign) Bulk Send Job API

{'$ref': './markdown/en/tags/bulk-send-job-tag-description.md'}

Dropbox Sign (HelloSign) Embedded API

{'$ref': './markdown/en/tags/embedded-tag-description.md'}

Dropbox Sign (HelloSign) Fax API

The Fax API from Dropbox Sign (HelloSign) — 4 operation(s) for fax.

Dropbox Sign (HelloSign) Fax Line API

{'$ref': './markdown/en/tags/fax-lines-tag-description.md'}

Dropbox Sign (HelloSign) OAuth API

{'$ref': './markdown/en/tags/oauth-tag-description.md'}

Dropbox Sign (HelloSign) Report API

{'$ref': './markdown/en/tags/report-tag-description.md'}

Dropbox Sign (HelloSign) Signature Request API

{'$ref': './markdown/en/tags/signature-request-tag-description.md'}

Dropbox Sign (HelloSign) Team API

{'$ref': './markdown/en/tags/team-tag-description.md'}

Dropbox Sign (HelloSign) Template API

{'$ref': './markdown/en/tags/template-tag-description.md'}

Dropbox Sign (HelloSign) Unclaimed Draft API

{'$ref': './markdown/en/tags/unclaimed-draft-tag-description.md'}

Scroll for all 12

MCP Servers 1

Model Context Protocol servers that expose these APIs to AI agents.

hellosign-mcp.yml

MCP SERVER

Event Specifications 1

AsyncAPI definitions for this provider's event-driven and streaming APIs.

Hellosign Events Webhooks

ASYNCAPI

Security Posture 4

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

Hellosign Authentication

http · 2 schemes

SECURITY

Hellosign Domain Security

TLSv1.3 · DMARC

SECURITY

Hellosign Vulnerability Disclosure

Intigriti · security.txt · contact published

SECURITY

Hellosign Trust Center

HIPAA, ISO 9001, SOC (CPA/AICPA attestation), Skyhigh Enterprise-Ready

SECURITY

Scopes 1

OAuth scopes governing access to this provider's APIs.

Hellosign Scopes

7 scopes

7 scopes

SCOPES

Agentic Access 1

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

Hellosign Agentic Access

73 operations · 46 acting

73 operations · 46 acting

AGENTIC

Resources

Get Started 4

Portal, sign-up, and the first successful call

Sandbox
Sandbox
 DeveloperPortal
DeveloperPortal
 GettingStarted
GettingStarted
 SignUp
SignUp

Documentation 2

Reference material describing how the API behaves

Documentation
Documentation
 APIReference
APIReference

Agent Surfaces 4

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess
AgenticAccess
 MCPServer
MCPServer
 LLMsTxt
LLMsTxt
 AgentSkill
AgentSkill

Design & Contract 7

Pagination, idempotency, versioning, errors, and events

ErrorCatalog
ErrorCatalog
 Conventions
Conventions
 Lifecycle
Lifecycle
 Conformance
Conformance
 Webhooks
Webhooks
 Components
Components
 DataModel
DataModel

Scroll for all 7

Build 3

SDKs, sample code, and the tooling you integrate with

Packages
Packages
 SDKs
SDKs
 GitHubOrganization
GitHubOrganization

Access & Security 7

Authentication, authorization, and security posture

DomainSecurity
DomainSecurity
 Authentication
Authentication
 OAuthScopes
OAuthScopes
 Compliance
Compliance
 TrustCenter
TrustCenter
 VulnerabilityDisclosure
VulnerabilityDisclosure
 Security
Security

Scroll for all 7

Operate 4

Status, limits, changes, and where to get help

StatusPage
StatusPage
 Deprecation
Deprecation
 ChangeLog
ChangeLog
 Support
Support

Commercial 3

Pricing, plans, and the legal terms of use

Pricing
Pricing
 TermsOfService
TermsOfService
 PrivacyPolicy
PrivacyPolicy

Source (apis.yml)

apis.yml Raw ↑ 
aid: hellosign
name: Dropbox Sign (HelloSign)
description: Dropbox Sign (formerly HelloSign) is an eSignature platform whose v3 REST API lets developers send documents
  for legally binding electronic signature, build reusable templates, embed signing directly in their own apps, run bulk send
  jobs, and manage accounts, teams, and API apps. The API exposes 73 operations across 12 product areas (Signature Request,
  Template, Bulk Send, Embedded, Account, Team, Report, Fax, Fax Line, Unclaimed Draft, API App, OAuth), with API-key and
  OAuth 2.0 authentication, 23 webhook event types, official SDKs in six languages, and a published hosted documentation MCP
  server. HelloSign was a Y Combinator company (S11), acquired by Dropbox in 2019 and rebranded to Dropbox Sign in 2022; the
  API base host remains api.hellosign.com.
url: https://raw.githubusercontent.com/api-evangelist/hellosign/refs/heads/main/apis.yml
accessModel:
  pricing: unknown
  onboarding: self-serve
  trial: false
  try_now: false
  public: false
  label: Self-serve signup
  confidence: medium
  source:
  - authentication
  generated: '2026-07-22'
  method: derived
image: https://github.com/hellosign.png
x-type: company
x-source: vc-portfolio
x-backed-by:
- y-combinator
x-tier: enriched
x-tier-reason: real-api-enriched
specificationVersion: '0.20'
created: '2026-07-17'
modified: '2026-07-19'
tags:
- Company
- eSignature
- Electronic Signatures
- Documents
- Digital Agreements
- Signature Workflow
- Embedded Signing
- Compliance
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
apis:
- aid: hellosign:hellosign-account-api
  name: Dropbox Sign (HelloSign) Account API
  description: '{''$ref'': ''./markdown/en/tags/account-tag-description.md''}'
  humanURL: https://developers.hellosign.com/
  baseURL: https://api.hellosign.com/v3
  tags:
  - Account
  properties:
  - type: OpenAPI
    url: openapi/hellosign-account-api-openapi.yml
- aid: hellosign:hellosign-api-app-api
  name: Dropbox Sign (HelloSign) Api App API
  description: '{''$ref'': ''./markdown/en/tags/api-app-tag-description.md''}'
  humanURL: https://developers.hellosign.com/
  baseURL: https://api.hellosign.com/v3
  tags:
  - Api App
  properties:
  - type: OpenAPI
    url: openapi/hellosign-api-app-api-openapi.yml
- aid: hellosign:hellosign-bulk-send-job-api
  name: Dropbox Sign (HelloSign) Bulk Send Job API
  description: '{''$ref'': ''./markdown/en/tags/bulk-send-job-tag-description.md''}'
  humanURL: https://developers.hellosign.com/
  baseURL: https://api.hellosign.com/v3
  tags:
  - Bulk Send Job
  properties:
  - type: OpenAPI
    url: openapi/hellosign-bulk-send-job-api-openapi.yml
- aid: hellosign:hellosign-embedded-api
  name: Dropbox Sign (HelloSign) Embedded API
  description: '{''$ref'': ''./markdown/en/tags/embedded-tag-description.md''}'
  humanURL: https://developers.hellosign.com/
  baseURL: https://api.hellosign.com/v3
  tags:
  - Embedded
  properties:
  - type: OpenAPI
    url: openapi/hellosign-embedded-api-openapi.yml
- aid: hellosign:hellosign-fax-api
  name: Dropbox Sign (HelloSign) Fax API
  description: The Fax API from Dropbox Sign (HelloSign) — 4 operation(s) for fax.
  humanURL: https://developers.hellosign.com/
  baseURL: https://api.hellosign.com/v3
  tags:
  - Fax
  properties:
  - type: OpenAPI
    url: openapi/hellosign-fax-api-openapi.yml
- aid: hellosign:hellosign-fax-line-api
  name: Dropbox Sign (HelloSign) Fax Line API
  description: '{''$ref'': ''./markdown/en/tags/fax-lines-tag-description.md''}'
  humanURL: https://developers.hellosign.com/
  baseURL: https://api.hellosign.com/v3
  tags:
  - Fax Line
  properties:
  - type: OpenAPI
    url: openapi/hellosign-fax-line-api-openapi.yml
- aid: hellosign:hellosign-oauth-api
  name: Dropbox Sign (HelloSign) OAuth API
  description: '{''$ref'': ''./markdown/en/tags/oauth-tag-description.md''}'
  humanURL: https://developers.hellosign.com/
  baseURL: https://api.hellosign.com/v3
  tags:
  - OAuth
  properties:
  - type: OpenAPI
    url: openapi/hellosign-oauth-api-openapi.yml
- aid: hellosign:hellosign-report-api
  name: Dropbox Sign (HelloSign) Report API
  description: '{''$ref'': ''./markdown/en/tags/report-tag-description.md''}'
  humanURL: https://developers.hellosign.com/
  baseURL: https://api.hellosign.com/v3
  tags:
  - Report
  properties:
  - type: OpenAPI
    url: openapi/hellosign-report-api-openapi.yml
- aid: hellosign:hellosign-signature-request-api
  name: Dropbox Sign (HelloSign) Signature Request API
  description: '{''$ref'': ''./markdown/en/tags/signature-request-tag-description.md''}'
  humanURL: https://developers.hellosign.com/
  baseURL: https://api.hellosign.com/v3
  tags:
  - Signature Request
  properties:
  - type: OpenAPI
    url: openapi/hellosign-signature-request-api-openapi.yml
- aid: hellosign:hellosign-team-api
  name: Dropbox Sign (HelloSign) Team API
  description: '{''$ref'': ''./markdown/en/tags/team-tag-description.md''}'
  humanURL: https://developers.hellosign.com/
  baseURL: https://api.hellosign.com/v3
  tags:
  - Team
  properties:
  - type: OpenAPI
    url: openapi/hellosign-team-api-openapi.yml
- aid: hellosign:hellosign-template-api
  name: Dropbox Sign (HelloSign) Template API
  description: '{''$ref'': ''./markdown/en/tags/template-tag-description.md''}'
  humanURL: https://developers.hellosign.com/
  baseURL: https://api.hellosign.com/v3
  tags:
  - Template
  properties:
  - type: OpenAPI
    url: openapi/hellosign-template-api-openapi.yml
- aid: hellosign:hellosign-unclaimed-draft-api
  name: Dropbox Sign (HelloSign) Unclaimed Draft API
  description: '{''$ref'': ''./markdown/en/tags/unclaimed-draft-tag-description.md''}'
  humanURL: https://developers.hellosign.com/
  baseURL: https://api.hellosign.com/v3
  tags:
  - Unclaimed Draft
  properties:
  - type: OpenAPI
    url: openapi/hellosign-unclaimed-draft-api-openapi.yml
common:
- type: AgenticAccess
  url: agentic-access/hellosign-agentic-access.yml
- type: DomainSecurity
  url: security/hellosign-domain-security.yml
- type: Authentication
  url: authentication/hellosign-authentication.yml
- type: OAuthScopes
  url: scopes/hellosign-scopes.yml
- type: MCPServer
  url: mcp/hellosign-mcp.yml
- type: LLMsTxt
  url: llms/hellosign-llms.txt
- type: Packages
  url: packages/hellosign-packages.yml
- type: SDKs
  url: packages/hellosign-packages.yml
- type: ErrorCatalog
  url: errors/hellosign-error-codes.yml
- type: Conventions
  url: conventions/hellosign-conventions.yml
- type: Lifecycle
  url: lifecycle/hellosign-lifecycle.yml
- type: StatusPage
  url: https://status.hellosign.com/
- type: Deprecation
  url: lifecycle/hellosign-lifecycle.yml
- type: Conformance
  url: conformance/hellosign-conformance.yml
- type: Compliance
  url: https://sign.dropbox.com/trust
- type: TrustCenter
  url: security/hellosign-trust-center.yml
- type: VulnerabilityDisclosure
  url: security/hellosign-vulnerability-disclosure.yml
- type: Security
  url: https://app.intigriti.com/programs/dropbox/dropbox-vdp
- type: Webhooks
  url: asyncapi/hellosign-events-webhooks.yml
- type: AgentSkill
  url: skills/_index.yml
- type: Sandbox
  url: sandbox/hellosign-sandbox.yml
- type: Components
  url: components/hellosign-components.yml
- type: DataModel
  url: data-model/hellosign-data-model.yml
- type: ChangeLog
  url: changelog/hellosign-changelog.yml
- type: DeveloperPortal
  url: https://developers.hellosign.com/
- type: Documentation
  url: https://developers.hellosign.com/docs/overview/
- type: APIReference
  url: https://developers.hellosign.com/api/reference/
- type: GettingStarted
  url: https://developers.hellosign.com/api/api-quickstart
- type: Support
  url: https://help.dropbox.com/sign
- type: GitHubOrganization
  url: https://github.com/hellosign
- type: Pricing
  url: https://sign.dropbox.com/products/api
- type: SignUp
  url: https://app.hellosign.com/account/signUp
- type: TermsOfService
  url: https://www.hellosign.com/terms
- type: PrivacyPolicy
  url: https://www.hellosign.com/privacy
x-enrichment:
  date: '2026-07-19'
  status: backfilled
  pass: local-v1
  note: backfilled from .gitignore signal + verified work evidence