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 13 APIs on the APIs.io network, including Account API, Api App API, Bulk Send Job API, and 10 more. Tagged areas include Company, E-Signature, 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 30 more developer resources.

🌐 Visit website 📡 Source on GitHub

57.4/100 strong ▬ flat Agent 51/100 agent ready saas Full breakdown ↓
scored 2026-09-06 · rubric v0.19.0

1 APIs 1 MCP Servers

Company E-Signature Electronic Signatures DocumentsDigital AgreementsSignature WorkflowEmbedded Signing Compliance

Kin Score

Kin Score How this is scored →
scored 2026-09-06 · rubric v0.19.0

Composite quality — 57.4/100 · strong

Contract Quality 16.0 / 25

Developer Ergonomics 13.0 / 20

Access Clarity 12.1 / 20

Operational Transparency 6.5 / 13

Contract Governance 2.2 / 12

Discoverability 7.6 / 10

Agent readiness — 51/100 · agent ready

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 6 / 6

MCP Server 12 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 8 / 8

Request/Response Examples 7 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 6 / 6

Agent Skills 5 / 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 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

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/hellosign: 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 13

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

Open Collections 13

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

MCP Servers 1

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

Scopes 1

OAuth scopes governing access to this provider's APIs.

Get Started 4

Portal, sign-up, and the first successful call

Sandbox

DeveloperPortal

GettingStarted

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

MCPServer

LLMsTxt

AgentSkill

Design & Contract 7

Pagination, idempotency, versioning, errors, and events

ErrorCatalog

Conventions

Lifecycle

Conformance

Webhooks

Components

DataModel

Scroll for all 7

Build 4

SDKs, sample code, and the tooling you integrate with

PostmanWorkspace

PostmanWorkspace

Packages

Packages

SDKs

SDKs

GitHubOrganization

GitHubOrganization

Access & Security 7

Authentication, authorization, and security posture

DomainSecurity

Authentication

OAuthScopes

Compliance

TrustCenter

VulnerabilityDisclosure

VulnerabilityDisclosure

Security

Security

Scroll for all 7

Operate 4

Status, limits, changes, and where to get help

StatusPage

Deprecation

ChangeLog

Support

Commercial 3

Pricing, plans, and the legal terms of use

Pricing

Pricing

TermsOfService

TermsOfService

PrivacyPolicy

PrivacyPolicy

Other 2

Properties that don't map to a standard resource type

ParentCompany

ParentCompany

Overlay

Overlay

Source (apis.yml)

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
deliveryModel:
  model: saas
  open_source: false
  commercial: true
  callable_host: true
  label: Hosted service · you call their endpoint
  confidence: high
  source:
  - openapi
  - pricing
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source:
  - authentication
  - scopes
  - security
  - sandbox
  generated: '2026-09-03'
  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: '0.23'
created: '2026-07-17'
modified: '2026-07-19'
tags:
- Company
- E-Signature
- Electronic Signatures
- Documents
- Digital Agreements
- Signature Workflow
- Embedded Signing
- Compliance
tags_raw:
- 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
  tags_raw:
  - 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:
  - Authentication
  tags_raw:
  - 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
- aid: hellosign:hellosign-callbacks-and-events-api
  name: Dropbox Sign (HelloSign) Callbacks and Events API
  description: The Callbacks and Events API from Dropbox Sign (HelloSign) — 0 operation(s) for callbacks and events.
  humanURL: https://developers.hellosign.com/
  baseURL: https://api.hellosign.com/v3
  tags:
  - Callbacks and Events
  properties:
  - type: OpenAPI
    url: openapi/hellosign-callbacks-and-events-api-openapi.yml
common:
- type: ParentCompany
  url: https://apis.io/providers/dropbox/
  name: Dropbox
  x-relationship: acquired
  x-evidence: 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.
- type: Overlay
  url: overlays/hellosign-openapi-overlay.yaml
- type: PostmanWorkspace
  url: https://www.postman.com/kinlaneapi/dropbox-sign-hellosign/overview
- 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

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