Quo website screenshot

Quo

Quo (formerly OpenPhone) is an AI-powered business communication platform that unifies calls, texts, and contacts in one shared workspace for startups and small businesses. Its REST Public API (https://api.quo.com/v1) lets developers send and receive SMS, manage contacts, conversations, and tasks, retrieve AI-generated call summaries and transcripts, and subscribe to Standard-Webhooks-signed events for messages and calls. Authentication is via a workspace API key sent in the Authorization header. This profile was added to the API Evangelist network from VC portfolio discovery and enriched from Quo's live developer documentation and published OpenAPI.

Quo publishes 9 APIs on the APIs.io network, including Calls API, Contact Custom Fields API, Contacts API, and 6 more. Tagged areas include Company, Communications, Messaging, SMS, and Voice.

The Quo catalog on APIs.io includes 1 event-driven AsyncAPI specification.

Quo’s developer surface includes documentation, API reference, getting-started guide, support, pricing, changelog, authentication, and 13 more developer resources.

🌐 Visit website 📡 Source on GitHub
51.4/100 developing ▬ flat Agent 36/100 agent ready Full breakdown ↓
scored 2026-08-20 · rubric v0.12.0
AccessSelf serve
9 APIs 1 MCP Servers
CompanyCommunicationsMessagingSMSVoiceContactsWebhook

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-08-20 · rubric v0.12.0
Composite quality — 51.4/100 · developing
Contract Quality 14.9 / 21
Developer Ergonomics 9.6 / 17
Access Clarity 6.3 / 17
Operational Transparency 3.5 / 11
Contract Governance 1.7 / 10
Discoverability 6.9 / 9
Regulatory Posture 5.4 / 15
Agent readiness — 36/100 · agent ready
Machine-Readable Contract 18 / 18
Agentic Access Contract 0 / 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 7 / 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
A2A Agent Card 0 / 8
Dry-Run / Simulate Mode 0 / 4
Regulatory Posture applies to this provider. Its tags matched the Telecommunications regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.
The six quality facets above are damped to 85 points between them, because the conditional facet above carries the other 15. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 85% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.
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/quo: 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 9

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

Quo Calls API

Operations related to calls

Quo Contact Custom Fields API

The Contact Custom Fields API from Quo — 1 operation(s) for contact custom fields.

Quo Contacts API

Operations related to contacts

Quo Conversations API

Operations related to conversations

Quo Messages API

Operations related to text messages

Quo Phone Numbers API

Operations related to phone numbers

Quo Tasks API

The Tasks API from Quo — 10 operation(s) for tasks.

Quo Users API

Operations related to users

Quo Webhooks API

Operations related to webhooks

Scroll for all 9

Open Collections 10

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

API Collection

OPEN COLLECTION

Quo Public Calls API

OPEN COLLECTION

Quo Public Calls Contact Custom Fields API

OPEN COLLECTION

Quo Public Calls Contacts API

OPEN COLLECTION

Quo Public Calls Conversations API

OPEN COLLECTION

Quo Public Calls Messages API

OPEN COLLECTION

Quo Public Calls Phone Numbers API

OPEN COLLECTION

Quo Public Calls Tasks API

OPEN COLLECTION

Quo Public Calls Users API

OPEN COLLECTION

Quo Public Calls Webhooks API

OPEN COLLECTION

Scroll for all 10

MCP Servers 1

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

Quo API MCP (candidate)

Candidate Model Context Protocol tool surface derived from the Quo Public API v1 OpenAPI operations. Quo markets a "Quo MCP" capability on quo.com, but no hosted/remote MCP serv...

MCP SERVER

Event Specifications 1

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

Quo Webhooks

ASYNCAPI

Security Posture 3

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

Quo Authentication

apiKey · 1 scheme

SECURITY

Quo Domain Security

TLSv1.3 · DMARC

SECURITY

Quo Trust Center

SOC 2, HIPAA, GDPR

SECURITY

Resources

Get Started 2

Portal, sign-up, and the first successful call

DeveloperPortal
DeveloperPortal
 GettingStarted
GettingStarted

Documentation 2

Reference material describing how the API behaves

Documentation
Documentation
 APIReference
APIReference

Agent Surfaces 3

MCP servers, agent skills, and machine-readable catalogs

LLMsTxt
LLMsTxt
 MCPServer
MCPServer
 AgentSkill
AgentSkill

Design & Contract 2

Pagination, idempotency, versioning, errors, and events

Conformance
Conformance
 Webhooks
Webhooks

Access & Security 4

Authentication, authorization, and security posture

Authentication
Authentication
 DomainSecurity
DomainSecurity
 TrustCenter
TrustCenter
 Compliance
Compliance

Operate 3

Status, limits, changes, and where to get help

Support
Support
 ChangeLog
ChangeLog
 Deprecation
Deprecation

Commercial 2

Pricing, plans, and the legal terms of use

Pricing
Pricing
 TermsOfService
TermsOfService

Company 1

The organization behind the API

Website
Website

Other 1

Properties that don't map to a standard resource type

Overlay
Overlay

Source (apis.yml)

apis.yml Raw ↑ 
aid: quo
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://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/quo.png
name: Quo
description: Quo (formerly OpenPhone) is an AI-powered business communication platform that unifies calls, texts, and contacts
  in one shared workspace for startups and small businesses. Its REST Public API (https://api.quo.com/v1) lets developers
  send and receive SMS, manage contacts, conversations, and tasks, retrieve AI-generated call summaries and transcripts, and
  subscribe to Standard-Webhooks-signed events for messages and calls. Authentication is via a workspace API key sent in the
  Authorization header. This profile was added to the API Evangelist network from VC portfolio discovery and enriched from
  Quo's live developer documentation and published OpenAPI.
url: https://raw.githubusercontent.com/api-evangelist/quo/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- craft-ventures
- general-catalyst
- kindred-ventures
x-tier: stub
x-tier-reason: portfolio-lead
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-20'
tags:
- Company
- Communications
- Messaging
- SMS
- Voice
- Contacts
- Webhook
tags_raw:
- Company
- Communication
- Messaging
- SMS
- Voice
- Contacts
- Webhooks
- API
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
apis:
- aid: quo:quo-calls-api
  name: Quo Calls API
  description: Operations related to calls
  humanURL: https://www.quo.com/api
  baseURL: https://api.quo.com
  tags:
  - Calls
  properties:
  - type: OpenAPI
    url: openapi/quo-calls-api-openapi.yml
  - type: APIReference
    url: https://www.quo.com/docs/mdx/api-reference/introduction
  - type: Documentation
    url: https://www.quo.com/docs
  - type: GettingStarted
    url: https://www.quo.com/docs/mdx/api-reference/send-your-first-message
  - type: Authentication
    url: authentication/quo-authentication.yml
  - type: Conventions
    url: conventions/quo-conventions.yml
  - type: ErrorCatalog
    url: errors/quo-problem-types.yml
  - type: DataModel
    url: data-model/quo-data-model.yml
  - type: Webhooks
    url: asyncapi/quo-webhooks.yml
  - type: Lifecycle
    url: lifecycle/quo-lifecycle.yml
  - type: ChangeLog
    url: changelog/quo-changelog.yml
- aid: quo:quo-contact-custom-fields-api
  name: Quo Contact Custom Fields API
  description: The Contact Custom Fields API from Quo — 1 operation(s) for contact custom fields.
  humanURL: https://www.quo.com/api
  baseURL: https://api.quo.com
  tags:
  - Contact Custom Fields
  properties:
  - type: OpenAPI
    url: openapi/quo-contact-custom-fields-api-openapi.yml
  - type: APIReference
    url: https://www.quo.com/docs/mdx/api-reference/introduction
  - type: Documentation
    url: https://www.quo.com/docs
  - type: GettingStarted
    url: https://www.quo.com/docs/mdx/api-reference/send-your-first-message
  - type: Authentication
    url: authentication/quo-authentication.yml
  - type: Conventions
    url: conventions/quo-conventions.yml
  - type: ErrorCatalog
    url: errors/quo-problem-types.yml
  - type: DataModel
    url: data-model/quo-data-model.yml
  - type: Webhooks
    url: asyncapi/quo-webhooks.yml
  - type: Lifecycle
    url: lifecycle/quo-lifecycle.yml
  - type: ChangeLog
    url: changelog/quo-changelog.yml
- aid: quo:quo-contacts-api
  name: Quo Contacts API
  description: Operations related to contacts
  humanURL: https://www.quo.com/api
  baseURL: https://api.quo.com
  tags:
  - Contacts
  properties:
  - type: OpenAPI
    url: openapi/quo-contacts-api-openapi.yml
  - type: APIReference
    url: https://www.quo.com/docs/mdx/api-reference/introduction
  - type: Documentation
    url: https://www.quo.com/docs
  - type: GettingStarted
    url: https://www.quo.com/docs/mdx/api-reference/send-your-first-message
  - type: Authentication
    url: authentication/quo-authentication.yml
  - type: Conventions
    url: conventions/quo-conventions.yml
  - type: ErrorCatalog
    url: errors/quo-problem-types.yml
  - type: DataModel
    url: data-model/quo-data-model.yml
  - type: Webhooks
    url: asyncapi/quo-webhooks.yml
  - type: Lifecycle
    url: lifecycle/quo-lifecycle.yml
  - type: ChangeLog
    url: changelog/quo-changelog.yml
- aid: quo:quo-conversations-api
  name: Quo Conversations API
  description: Operations related to conversations
  humanURL: https://www.quo.com/api
  baseURL: https://api.quo.com
  tags:
  - Conversations
  properties:
  - type: OpenAPI
    url: openapi/quo-conversations-api-openapi.yml
  - type: APIReference
    url: https://www.quo.com/docs/mdx/api-reference/introduction
  - type: Documentation
    url: https://www.quo.com/docs
  - type: GettingStarted
    url: https://www.quo.com/docs/mdx/api-reference/send-your-first-message
  - type: Authentication
    url: authentication/quo-authentication.yml
  - type: Conventions
    url: conventions/quo-conventions.yml
  - type: ErrorCatalog
    url: errors/quo-problem-types.yml
  - type: DataModel
    url: data-model/quo-data-model.yml
  - type: Webhooks
    url: asyncapi/quo-webhooks.yml
  - type: Lifecycle
    url: lifecycle/quo-lifecycle.yml
  - type: ChangeLog
    url: changelog/quo-changelog.yml
- aid: quo:quo-messages-api
  name: Quo Messages API
  description: Operations related to text messages
  humanURL: https://www.quo.com/api
  baseURL: https://api.quo.com
  tags:
  - Message
  tags_raw:
  - Messages
  properties:
  - type: OpenAPI
    url: openapi/quo-messages-api-openapi.yml
  - type: APIReference
    url: https://www.quo.com/docs/mdx/api-reference/introduction
  - type: Documentation
    url: https://www.quo.com/docs
  - type: GettingStarted
    url: https://www.quo.com/docs/mdx/api-reference/send-your-first-message
  - type: Authentication
    url: authentication/quo-authentication.yml
  - type: Conventions
    url: conventions/quo-conventions.yml
  - type: ErrorCatalog
    url: errors/quo-problem-types.yml
  - type: DataModel
    url: data-model/quo-data-model.yml
  - type: Webhooks
    url: asyncapi/quo-webhooks.yml
  - type: Lifecycle
    url: lifecycle/quo-lifecycle.yml
  - type: ChangeLog
    url: changelog/quo-changelog.yml
- aid: quo:quo-phone-numbers-api
  name: Quo Phone Numbers API
  description: Operations related to phone numbers
  humanURL: https://www.quo.com/api
  baseURL: https://api.quo.com
  tags:
  - Phone Numbers
  properties:
  - type: OpenAPI
    url: openapi/quo-phone-numbers-api-openapi.yml
  - type: APIReference
    url: https://www.quo.com/docs/mdx/api-reference/introduction
  - type: Documentation
    url: https://www.quo.com/docs
  - type: GettingStarted
    url: https://www.quo.com/docs/mdx/api-reference/send-your-first-message
  - type: Authentication
    url: authentication/quo-authentication.yml
  - type: Conventions
    url: conventions/quo-conventions.yml
  - type: ErrorCatalog
    url: errors/quo-problem-types.yml
  - type: DataModel
    url: data-model/quo-data-model.yml
  - type: Webhooks
    url: asyncapi/quo-webhooks.yml
  - type: Lifecycle
    url: lifecycle/quo-lifecycle.yml
  - type: ChangeLog
    url: changelog/quo-changelog.yml
- aid: quo:quo-tasks-api
  name: Quo Tasks API
  description: The Tasks API from Quo — 10 operation(s) for tasks.
  humanURL: https://www.quo.com/api
  baseURL: https://api.quo.com
  tags:
  - Task
  tags_raw:
  - Tasks
  properties:
  - type: OpenAPI
    url: openapi/quo-tasks-api-openapi.yml
  - type: APIReference
    url: https://www.quo.com/docs/mdx/api-reference/introduction
  - type: Documentation
    url: https://www.quo.com/docs
  - type: GettingStarted
    url: https://www.quo.com/docs/mdx/api-reference/send-your-first-message
  - type: Authentication
    url: authentication/quo-authentication.yml
  - type: Conventions
    url: conventions/quo-conventions.yml
  - type: ErrorCatalog
    url: errors/quo-problem-types.yml
  - type: DataModel
    url: data-model/quo-data-model.yml
  - type: Webhooks
    url: asyncapi/quo-webhooks.yml
  - type: Lifecycle
    url: lifecycle/quo-lifecycle.yml
  - type: ChangeLog
    url: changelog/quo-changelog.yml
- aid: quo:quo-users-api
  name: Quo Users API
  description: Operations related to users
  humanURL: https://www.quo.com/api
  baseURL: https://api.quo.com
  tags:
  - User
  tags_raw:
  - Users
  properties:
  - type: OpenAPI
    url: openapi/quo-users-api-openapi.yml
  - type: APIReference
    url: https://www.quo.com/docs/mdx/api-reference/introduction
  - type: Documentation
    url: https://www.quo.com/docs
  - type: GettingStarted
    url: https://www.quo.com/docs/mdx/api-reference/send-your-first-message
  - type: Authentication
    url: authentication/quo-authentication.yml
  - type: Conventions
    url: conventions/quo-conventions.yml
  - type: ErrorCatalog
    url: errors/quo-problem-types.yml
  - type: DataModel
    url: data-model/quo-data-model.yml
  - type: Webhooks
    url: asyncapi/quo-webhooks.yml
  - type: Lifecycle
    url: lifecycle/quo-lifecycle.yml
  - type: ChangeLog
    url: changelog/quo-changelog.yml
- aid: quo:quo-webhooks-api
  name: Quo Webhooks API
  description: Operations related to webhooks
  humanURL: https://www.quo.com/api
  baseURL: https://api.quo.com
  tags:
  - Webhook
  tags_raw:
  - Webhooks
  properties:
  - type: OpenAPI
    url: openapi/quo-webhooks-api-openapi.yml
  - type: APIReference
    url: https://www.quo.com/docs/mdx/api-reference/introduction
  - type: Documentation
    url: https://www.quo.com/docs
  - type: GettingStarted
    url: https://www.quo.com/docs/mdx/api-reference/send-your-first-message
  - type: Authentication
    url: authentication/quo-authentication.yml
  - type: Conventions
    url: conventions/quo-conventions.yml
  - type: ErrorCatalog
    url: errors/quo-problem-types.yml
  - type: DataModel
    url: data-model/quo-data-model.yml
  - type: Webhooks
    url: asyncapi/quo-webhooks.yml
  - type: Lifecycle
    url: lifecycle/quo-lifecycle.yml
  - type: ChangeLog
    url: changelog/quo-changelog.yml
common:
- type: Overlay
  url: overlays/quo-public-api-v1-overlay.yaml
- type: Website
  url: https://quo.com
- type: DeveloperPortal
  url: https://www.quo.com/docs
- type: Documentation
  url: https://www.quo.com/docs
- type: APIReference
  url: https://www.quo.com/docs/mdx/api-reference/introduction
- type: GettingStarted
  url: https://www.quo.com/docs/mdx/api-reference/send-your-first-message
- type: Support
  url: https://support.quo.com
- type: Pricing
  url: https://www.quo.com/docs/mdx/pricing-support/pricing-overview
- type: TermsOfService
  url: https://www.quo.com/docs/mdx/pricing-support/terms-of-service
- type: ChangeLog
  url: https://support.quo.com/changelog
- type: LLMsTxt
  url: llms/quo-llms.txt
- type: Authentication
  url: authentication/quo-authentication.yml
- type: Conformance
  url: conformance/quo-conformance.yml
- type: DomainSecurity
  url: security/quo-domain-security.yml
- type: TrustCenter
  url: security/quo-trust-center.yml
- type: Compliance
  url: security/quo-trust-center.yml
- type: Deprecation
  url: lifecycle/quo-lifecycle.yml
- type: Webhooks
  url: asyncapi/quo-webhooks.yml
- type: MCPServer
  url: mcp/quo-mcp.yml
- type: AgentSkill
  url: skills/_index.yml
x-enrichment:
  date: '2026-07-20'
  status: enriched
  artifacts_added: 16
  pass: local-v1