Justt

Justt is an AI-native chargeback management and dispute-representment platform for high-volume merchants. Its Dynamic Arguments engine assembles evidence-backed representment packages for card disputes across 30+ payment service providers (Stripe, Adyen, PayPal, Braintree, Checkout.com, Worldpay, Chase Paymentech, Nuvei and others), and it also handles pre-chargeback alerts from Ethoca, Verifi CDRN and RDR. Justt publishes a public developer portal at developers.justt.ai with three OpenAPI definitions — a REST API for chargebacks, transactions, evidence, files, merchants and integrations; a Pre-Chargeback Alerts API; and an OpenAPI 3.1 webhook-events specification covering eleven signed event types — plus an RFC 9727 /.well-known/api-catalog, an llms.txt documentation index, a sandbox environment, and a Vanta-hosted trust center.

Justt publishes 3 APIs on the APIs.io network: REST API, Pre-Chargeback Alerts API, and Webhook Events. Tagged areas include Company, Payments, Chargebacks, Disputes, and Fraud.

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

Justt’s developer surface includes authentication, documentation, API reference, getting-started guide, support, engineering blog, sandbox, and 28 more developer resources.

🌐 Visit website 📡 Source on GitHub
61.0/100 strong ▬ flat Agent 52/100 agent ready Full breakdown ↓
scored 2026-08-25 · rubric v0.14.0
3 APIs 1 MCP Servers
CompanyPaymentsChargebacksDisputesFraudRiskFinancial ServicesE-CommerceArtificial IntelligenceWebhooks

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-08-25 · rubric v0.14.0
Composite quality — 61.0/100 · strong
Contract Quality 11.5 / 21
Developer Ergonomics 11.2 / 17
Access Clarity 8.5 / 17
Operational Transparency 5.8 / 11
Contract Governance 3.1 / 10
Discoverability 7.9 / 9
Regulatory Posture 9.4 / 15
Agent readiness — 52/100 · agent ready
Machine-Readable Contract 18 / 18
Agentic Access Contract 10 / 10
Documented Reversibility 0 / 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 4 / 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 5 / 5
Registration Without a Human 0 / 6
Agentic Commerce Surface 0 / 5
Regulatory Posture applies to this provider. Its tags matched the Payments 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/justt: 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 3

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

Justt REST API

The Justt REST API lets merchants read and manage chargebacks, enrich them with transaction data and evidence files, decide whether Justt should fight or accept a dispute, manag...

Justt Pre-Chargeback Alerts API

Justt official REST API for pre-chargeback alerts. Retrieve alerts sourced from Ethoca, Verifi CDRN and RDR by search criteria or by id, so a merchant can refund or resolve a tr...

Justt Webhook Events

OpenAPI 3.1 specification of the eleven webhook events Justt sends to merchant endpoints — chargeback created/updated/status-updated, evidence submitted, chargeback accepted, pr...

Arazzo Workflows 4

Multi-step API workflows described with the Arazzo specification.

Work a Justt pre-chargeback alert to a reported outcome

Pull pre-chargeback alerts from Ethoca / Verifi, read one, and report its outcome back to Justt using the alert networks' own outcome vocabulary. Note the read operations and th...

ARAZZO

Drive a chargeback through its lifecycle in the Justt sandbox

Create a test chargeback from raw Stripe dispute data in the sandbox, advance it to under_review, then resolve it as won — firing a webhook at each transition so an integration ...

ARAZZO

Submit evidence for a Justt chargeback

Read an open chargeback, upload an evidence file, submit it to the PSP, and poll the asynchronous submission to a terminal state.

ARAZZO

Triage Justt chargebacks and set the representment decision

List open chargebacks, enrich one with additional merchant data, and override whether Justt should represent it. Acceptance is deliberately NOT part of this workflow — it is irr...

ARAZZO

MCP Servers 1

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

Justt MCP Server

MCP SERVER

Pricing Plans 1

Published pricing tiers and plan structures.

Justt Plans Pricing

0 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Justt Rate Limits

1 limits

RATE LIMITS

Event Specifications 1

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

Justt Webhook Events

ASYNCAPI

Security Posture 3

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

Justt Authentication

http/apiKey · 3 schemes

SECURITY

Justt Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Justt Trust Center

SOC 2 Type II, ISO 27001, ISO 27017, ISO 27018

SECURITY

Scopes 1

OAuth scopes governing access to this provider's APIs.

Justt Scopes

1 scope · authorizationCode

1 scopes

SCOPES

Agentic Access 1

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

Justt Agentic Access

23 operations · 13 acting · 13 human-in-the-loop

23 operations · 13 acting

AGENTIC

Resources

Get Started 4

Portal, sign-up, and the first successful call

DeveloperPortal
DeveloperPortal
 GettingStarted
GettingStarted
 Login
Login
 Sandbox
Sandbox

Documentation 2

Reference material describing how the API behaves

Documentation
Documentation
 APIReference
APIReference

Agent Surfaces 5

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess
AgenticAccess
 WellKnown
WellKnown
 MCPServer
MCPServer
 LLMsTxt
LLMsTxt
 AgentSkill
AgentSkill

Design & Contract 7

Pagination, idempotency, versioning, errors, and events

Conformance
Conformance
 ErrorCatalog
ErrorCatalog
 Lifecycle
Lifecycle
 Conventions
Conventions
 DataModel
DataModel
 Webhooks
Webhooks
 Arazzo
Arazzo

Scroll for all 7

Build 1

SDKs, sample code, and the tooling you integrate with

ToolCrosswalk
ToolCrosswalk

Access & Security 5

Authentication, authorization, and security posture

DomainSecurity
DomainSecurity
 Authentication
Authentication
 TrustCenter
TrustCenter
 Compliance
Compliance
 OAuthScopes
OAuthScopes

Operate 4

Status, limits, changes, and where to get help

Support
Support
 StatusPage
StatusPage
 Deprecation
Deprecation
 RateLimits
RateLimits

Commercial 3

Pricing, plans, and the legal terms of use

TermsOfService
TermsOfService
 PrivacyPolicy
PrivacyPolicy
 Plans
Plans

Company 2

The organization behind the API

Website
Website
 Blog
Blog

Other 2

Properties that don't map to a standard resource type

APICatalog
APICatalog
 Overlay
Overlay

Source (apis.yml)

apis.yml Raw ↑ 
aid: justt
name: Justt
description: Justt is an AI-native chargeback management and dispute-representment platform for high-volume merchants. Its
  Dynamic Arguments engine assembles evidence-backed representment packages for card disputes across 30+ payment service providers
  (Stripe, Adyen, PayPal, Braintree, Checkout.com, Worldpay, Chase Paymentech, Nuvei and others), and it also handles pre-chargeback
  alerts from Ethoca, Verifi CDRN and RDR. Justt publishes a public developer portal at developers.justt.ai with three OpenAPI
  definitions — a REST API for chargebacks, transactions, evidence, files, merchants and integrations; a Pre-Chargeback Alerts
  API; and an OpenAPI 3.1 webhook-events specification covering eleven signed event types — plus an RFC 9727 /.well-known/api-catalog,
  an llms.txt documentation index, a sandbox environment, and a Vanta-hosted trust center.
url: https://raw.githubusercontent.com/api-evangelist/justt/refs/heads/main/apis.yml
image: https://justt.ai/wp-content/uploads/2025/03/blog-7-1.jpg
x-type: company
x-source: harvest:secondary-market
specificationVersion: '0.20'
created: '2026-08-23'
modified: '2026-08-23'
tags:
- Company
- Payments
- Chargebacks
- Disputes
- Fraud
- Risk
- Financial Services
- E-Commerce
- Artificial Intelligence
- Webhooks
apis:
- aid: justt:rest-api
  name: Justt REST API
  description: The Justt REST API lets merchants read and manage chargebacks, enrich them with transaction data and evidence
    files, decide whether Justt should fight or accept a dispute, manage merchants and PSP integrations, record pre-chargeback
    alert outcomes, and request data-subject removal. Bearer API-key authentication over HTTPS; JSON request and response
    bodies.
  humanURL: https://developers.justt.ai/reference
  baseURL: https://api.justt.ai/v1
  image: https://justt.ai/wp-content/uploads/2025/03/blog-7-1.jpg
  tags:
  - Chargebacks
  - Disputes
  - Payments
  - Evidence
  - Merchants
  properties:
  - type: OpenAPI
    url: openapi/justt-rest-api-openapi-original.json
  - type: Documentation
    url: https://developers.justt.ai/docs/getting-started
  - type: APIReference
    url: https://developers.justt.ai/reference
- aid: justt:pre-chargeback-alerts
  name: Justt Pre-Chargeback Alerts API
  description: Justt official REST API for pre-chargeback alerts. Retrieve alerts sourced from Ethoca, Verifi CDRN and RDR
    by search criteria or by id, so a merchant can refund or resolve a transaction before it becomes a chargeback.
  humanURL: https://developers.justt.ai/reference/alertcontroller_findall
  baseURL: https://api.justt.ai/v1
  tags:
  - Pre-Chargeback Alerts
  - Prevention
  - Payments
  properties:
  - type: OpenAPI
    url: openapi/justt-pre-chargeback-alerts-openapi-original.json
  - type: Documentation
    url: https://developers.justt.ai/docs/prevention-tools-overview
- aid: justt:webhook-events
  name: Justt Webhook Events
  description: OpenAPI 3.1 specification of the eleven webhook events Justt sends to merchant endpoints — chargeback created/updated/status-updated,
    evidence submitted, chargeback accepted, pre-chargeback alert received/refund succeeded/refund failed/transaction matched,
    and CRM subscription cancellation success/failure. Payloads are signed HMAC-SHA256 and delivered with svix signature headers.
  humanURL: https://developers.justt.ai/docs/webhook-introduction
  baseURL: https://api.justt.ai/v1
  tags:
  - Webhooks
  - Events
  - Chargebacks
  properties:
  - type: OpenAPI
    url: asyncapi/justt-webhook-events-openapi-original.json
  - type: Webhooks
    url: asyncapi/justt-webhook-events.yml
  - type: Documentation
    url: https://developers.justt.ai/docs/webhook-events-event-types
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: AgenticAccess
  url: agentic-access/justt-agentic-access.yml
- type: DomainSecurity
  url: security/justt-domain-security.yml
- type: Authentication
  url: authentication/justt-authentication.yml
- type: Website
  url: https://justt.ai/
- type: DeveloperPortal
  url: https://developers.justt.ai/
- type: Documentation
  url: https://developers.justt.ai/docs/getting-started
- type: APIReference
  url: https://developers.justt.ai/reference
- type: GettingStarted
  url: https://developers.justt.ai/docs/getting-started
- type: Support
  url: https://developers.justt.ai/docs/contact-us
- type: Blog
  url: https://justt.ai/blog/
- type: Login
  url: https://app.justt.ai/
- type: TermsOfService
  url: https://justt.ai/terms-of-use/
- type: PrivacyPolicy
  url: https://justt.ai/privacy-policy/
- type: StatusPage
  url: https://status.justt.ai/
- type: TrustCenter
  url: https://trust.justt.ai/
- type: Compliance
  url: https://trust.justt.ai/
- type: APICatalog
  url: well-known/justt-well-known.yml
- type: WellKnown
  url: well-known/justt-well-known.yml
- type: MCPServer
  url: mcp/justt-mcp.yml
- type: ToolCrosswalk
  url: mcp/justt-tool-crosswalk.yml
- type: LLMsTxt
  url: llms/justt-llms.txt
- type: Overlay
  url: overlays/justt-rest-api-overlay.yaml
- type: Conformance
  url: conformance/justt-conformance.yml
- type: ErrorCatalog
  url: errors/justt-problem-types.yml
- type: Lifecycle
  url: lifecycle/justt-lifecycle.yml
- type: Deprecation
  url: https://developers.justt.ai/docs/legacy-api-to-rest-api-migration-guide
- type: OAuthScopes
  url: scopes/justt-scopes.yml
- type: Sandbox
  url: sandbox/justt-sandbox.yml
- type: Conventions
  url: conventions/justt-conventions.yml
- type: DataModel
  url: data-model/justt-data-model.yml
- type: Webhooks
  url: asyncapi/justt-webhook-events.yml
- type: AgentSkill
  url: skills/_index.yml
- type: Plans
  url: plans/justt-plans-pricing.yml
- type: RateLimits
  url: rate-limits/justt-rate-limits.yml
- type: Arazzo
  url: arazzo/_index.yml
x-enrichment:
  date: '2026-08-23'
  status: enriched
  artifacts_added: 38
  pass: local-v1

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