JustCall website screenshot

JustCall

JustCall is a cloud-based phone system and contact center platform that provides voice calling, SMS/MMS messaging, IVR, call analytics, and contact management for small and mid-sized businesses. The platform integrates with CRMs, helpdesks, and automation tools. JustCall exposes REST APIs and webhooks for programmatically managing calls, SMS, contacts, phone numbers, and call dispositions, authenticated via API key plus API secret in headers.

JustCall publishes 3 APIs on the APIs.io network: Calls API, Contacts API, and SMS API. Tagged areas include Voice, SMS, Cloud Phone, Contact Center, and Telephony.

JustCall’s developer surface includes authentication, documentation, pricing, signup flow, support, engineering blog, and 7 more developer resources.

🌐 Visit website 📡 Source on GitHub
31.3/100 thin ▬ flat Agent 28/100 agent aware Full breakdown ↓
scored 2026-07-28 · rubric v0.6
AccessSelf serve
4 APIs
VoiceSMSCloud PhoneContact CenterTelephonyCommunications

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-07-28 · rubric v0.6
Composite quality — 31.3/100 · thin
Contract Quality 14.6 / 25
Developer Ergonomics 7.0 / 20
Commercial Clarity 3.7 / 20
Operational Transparency 0.0 / 13
Governance 0.0 / 12
Discoverability 7.4 / 10
Agent readiness — 28/100 · agent aware
Machine-Readable Contract 18 / 18
Agentic Access Contract 10 / 10
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 0 / 7
Typed Event Surface 0 / 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
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/justcall: 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 4

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

JustCall REST API

REST API for placing calls, sending SMS and MMS messages, managing contacts, phone numbers, users, and call dispositions in JustCall. Authentication uses an API key and API secr...

JustCall Calls API

Manage and query voice calls handled through JustCall.

JustCall Contacts API

Create and manage contacts in the JustCall directory.

JustCall SMS API

Send and manage SMS/MMS messages.

Open Collections 1

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

JustCall REST API

OPEN COLLECTION

Security Posture 3

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

Justcall Authentication

apiKey · 1 scheme

SECURITY

Justcall Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Justcall Trust Center

SOC 2, ISO 27001, PCI DSS, HIPAA, CSA STAR

SECURITY

Agentic Access 1

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

Justcall Agentic Access

3 operations · 2 acting

3 operations · 2 acting

AGENTIC

Resources

Get Started 2

Portal, sign-up, and the first successful call

DeveloperPortal
DeveloperPortal
 Signup
Signup

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

Access & Security 3

Authentication, authorization, and security posture

TrustCenter
TrustCenter
 DomainSecurity
DomainSecurity
 Authentication
Authentication

Operate 1

Status, limits, changes, and where to get help

Support
Support

Commercial 1

Pricing, plans, and the legal terms of use

Pricing
Pricing

Company 3

The organization behind the API

LinkedIn
LinkedIn
 Website
Website
 Blog
Blog

Source (apis.yml)

apis.yml Raw ↑ 
aid: justcall
name: JustCall
description: JustCall is a cloud-based phone system and contact center platform that provides voice calling, SMS/MMS messaging,
  IVR, call analytics, and contact management for small and mid-sized businesses. The platform integrates with CRMs, helpdesks,
  and automation tools. JustCall exposes REST APIs and webhooks for programmatically managing calls, SMS, contacts, phone
  numbers, and call dispositions, authenticated via API key plus API secret in headers.
type: Index
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/justcall.png
tags:
- Voice
- SMS
- Cloud Phone
- Contact Center
- Telephony
- Communications
url: https://raw.githubusercontent.com/api-evangelist/justcall/refs/heads/main/apis.yml
created: '2026-05-11'
modified: '2026-05-11'
specificationVersion: '0.19'
apis:
- aid: justcall:rest-api
  name: JustCall REST API
  description: REST API for placing calls, sending SMS and MMS messages, managing contacts, phone numbers, users, and call
    dispositions in JustCall. Authentication uses an API key and API secret passed in the Authorization header. Webhooks notify
    on completed calls and SMS events.
  humanURL: https://developer.justcall.io/docs/overview
  baseURL: https://api.justcall.io/v2.1
  tags:
  - Voice
  - SMS
  - Telephony
  - Contact Center
  - Webhooks
  properties:
  - type: Documentation
    url: https://developer.justcall.io/docs/overview
  - type: APIReference
    url: https://developer.justcall.io/reference
  - type: Send SMS Endpoint
    url: https://developer.justcall.io/reference/texts_new_v21
  - type: Webhooks
    url: https://justcall.io/product/api-and-webhooks/
- aid: justcall:justcall-calls-api
  name: JustCall Calls API
  description: Manage and query voice calls handled through JustCall.
  humanURL: https://developer.justcall.io/docs/overview
  baseURL: https://api.justcall.io/v2.1
  tags:
  - Calls
  properties:
  - type: OpenAPI
    url: openapi/justcall-calls-api-openapi.yml
- aid: justcall:justcall-contacts-api
  name: JustCall Contacts API
  description: Create and manage contacts in the JustCall directory.
  humanURL: https://developer.justcall.io/docs/overview
  baseURL: https://api.justcall.io/v2.1
  tags:
  - Contacts
  properties:
  - type: OpenAPI
    url: openapi/justcall-contacts-api-openapi.yml
- aid: justcall:justcall-sms-api
  name: JustCall SMS API
  description: Send and manage SMS/MMS messages.
  humanURL: https://developer.justcall.io/docs/overview
  baseURL: https://api.justcall.io/v2.1
  tags:
  - SMS
  properties:
  - type: OpenAPI
    url: openapi/justcall-sms-api-openapi.yml
common:
- type: AgenticAccess
  url: agentic-access/justcall-agentic-access.yml
- type: TrustCenter
  url: security/justcall-trust-center.yml
- type: DomainSecurity
  url: security/justcall-domain-security.yml
- type: Authentication
  url: authentication/justcall-authentication.yml
- type: LinkedIn
  url: https://www.linkedin.com/company/justcall-io
- type: Website
  url: https://justcall.io
- type: Documentation
  url: https://developer.justcall.io/docs/overview
- type: DeveloperPortal
  url: https://justcall.io/developer-docs/
- type: Pricing
  url: https://justcall.io/pricing
- type: Signup
  url: https://justcall.io/signup
- type: Support
  url: https://help.justcall.io
- type: LlmsText
  url: https://developer.justcall.io/llms.txt
- url: https://justcall.io/blog/
  type: Blog
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com