Kickbox

Kickbox is an email verification and list cleaning service that helps senders improve deliverability by detecting invalid, disposable, role-based, and risky email addresses before they enter mailing lists. The platform offers real-time single verification, bulk batch verification, and a deliverability monitoring suite. Kickbox provides a simple HTTPS REST API authenticated by API key returning structured verification results with reason codes.

Kickbox publishes 5 APIs on the APIs.io network, including Account API, Batch API, Open API, and 2 more. Tagged areas include Email Verification, Email Validation, Deliverability, Data Quality, and Email.

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

Kickbox’s developer surface includes authentication, documentation, pricing, signup flow, support, engineering blog, API reference, and 31 more developer resources.

🌐 Visit website 📡 Source on GitHub

56.8/100 strong ▬ flat Agent 39/100 agent ready saas Full breakdown ↓
scored 2026-09-14 · rubric v0.22.0

AccessSelf serve

2 APIs 1 MCP Servers

Email Verification Email Validation Deliverability Data Quality Email

Kin Score

Kin Score How this is scored →
scored 2026-09-14 · rubric v0.22.0

Composite quality — 56.8/100 · strong

Contract Quality 13.4 / 23

Developer Ergonomics 13.0 / 18

Access Clarity 12.5 / 18

Operational Transparency 5.5 / 12

Contract Governance 0.5 / 11

Discoverability 6.8 / 9

Create-or-Update Ergonomics 0.0 / 10

Agent readiness — 39/100 · 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 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

Create-or-Update Ergonomics applies to this provider. This API accepts writes, so it carries 10 points of the composite. It is scored from the published contracts themselves: whether a caller can create-or-update in one call, whether the write accepts a key the caller already holds, and whether the response says which branch ran. Without that, every write needs a search-and-branch in front of it, and the first time that check is skipped a duplicate record is created. Scored against the observed mean rather than raw — a provider at the catalog average is unchanged by this facet, not penalised by it.

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/kickbox: 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 6

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

Kickbox Email Verification API

REST API for verifying the deliverability of email addresses in real time. Returns a result (deliverable, undeliverable, risky, unknown), a reason code, plus flags for role addr...

Kickbox Account API

Account balance and metadata.

Kickbox Batch API

Bulk CSV email verification.

Kickbox Open API

Free disposable-domain lookup (no auth).

Kickbox Verification API

Real-time email verification.

Kickbox Disposable API

The Disposable API from Kickbox — 1 operation(s) for disposable.

Open Collections 6

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

API Collection

OPEN COLLECTION

Kickbox Email Verification Account API

OPEN COLLECTION

Kickbox Email Verification Account Batch API

OPEN COLLECTION

Kickbox Email Verification Account Open API

OPEN COLLECTION

Kickbox Email Account Verification API

OPEN COLLECTION

Kickbox Email Verification API

OPEN COLLECTION

MCP Servers 1

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

Kickbox documentation MCP server (auth-gated)

MCP SERVER

Pricing Plans 1

Published pricing tiers and plan structures.

Kickbox Plans Pricing

13 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Kickbox Rate Limits

2 limits

RATE LIMITS

Event Specifications 1

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

Kickbox Batch Webhooks

ASYNCAPI

Security Posture 3

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

Kickbox Authentication

apiKey/http · 2 schemes

SECURITY

Kickbox Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Kickbox Trust Center

SOC 2, GDPR, CCPA

SECURITY

Agentic Access 1

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

Kickbox Agentic Access

5 operations · 1 acting

AGENTIC

Resources

Get Started 4

Portal, sign-up, and the first successful call

SignUp

DeveloperPortal

GettingStarted

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

LlmsText

LLMsTxt

MCPServer

AgentSkill

Design & Contract 6

Pagination, idempotency, versioning, errors, and events

Conventions

ErrorCatalog

Lifecycle

DataModel

Conformance

Webhooks

Build 4

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

Packages

SDKs

ToolCrosswalk

Access & Security 4

Authentication, authorization, and security posture

DomainSecurity

Authentication

TrustCenter

Compliance

Operate 5

Status, limits, changes, and where to get help

Support

HelpCenter

Contact

StatusPage

RateLimits

Commercial 4

Pricing, plans, and the legal terms of use

Pricing

TermsOfService

PrivacyPolicy

Plans

Company 4

The organization behind the API

LinkedIn

Website

Website

Blog

Blog

BlogRSS

BlogRSS

Source (apis.yml)

aid: kickbox
name: Kickbox
description: Kickbox is an email verification and list cleaning service that helps senders improve deliverability by detecting
  invalid, disposable, role-based, and risky email addresses before they enter mailing lists. The platform offers real-time
  single verification, bulk batch verification, and a deliverability monitoring suite. Kickbox provides a simple HTTPS REST
  API authenticated by API key returning structured verification results with reason codes.
type: Index
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: 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/kickbox.png
tags:
- Email Verification
- Email Validation
- Deliverability
- Data Quality
- Email
url: https://raw.githubusercontent.com/api-evangelist/kickbox/refs/heads/main/apis.yml
created: '2026-05-11'
modified: '2026-08-13'
specificationVersion: '0.23'
apis:
- aid: kickbox:verification-api
  name: Kickbox Email Verification API
  description: REST API for verifying the deliverability of email addresses in real time. Returns a result (deliverable, undeliverable,
    risky, unknown), a reason code, plus flags for role addresses, disposable domains, and free email providers. Authentication
    uses an API key supplied as a query string parameter or in the Authorization header. Sandbox mode is available for testing
    without consuming credits.
  humanURL: https://docs.kickbox.com
  baseURL: https://api.kickbox.com/v2
  tags:
  - Email Verification
  - Deliverability
  - Validation
  properties:
  - type: Documentation
    url: https://docs.kickbox.com
  - type: APIReference
    url: https://docs.kickbox.com/reference/single-verification
  - type: PHP SDK
    url: https://github.com/kickboxio/kickbox-php
  - type: Python SDK
    url: https://github.com/kickboxio/kickbox-python
  - type: GettingStarted
    url: https://docs.kickbox.com/docs/using-the-api
  - type: Sandbox
    url: sandbox/kickbox-sandbox.yml
- aid: kickbox:kickbox-account-api
  name: Kickbox Account API
  description: Account balance and metadata.
  humanURL: https://docs.kickbox.com
  baseURL: https://api.kickbox.com/v2
  tags:
  - Account
  properties:
  - type: OpenAPI
    url: openapi/kickbox-account-api-openapi.yml
  - type: Overlay
    url: overlays/kickbox-account-api-overlay.yaml
- aid: kickbox:kickbox-batch-api
  name: Kickbox Batch API
  description: Bulk CSV email verification.
  humanURL: https://docs.kickbox.com
  baseURL: https://api.kickbox.com/v2
  tags:
  - Batch
  properties:
  - type: OpenAPI
    url: openapi/kickbox-batch-api-openapi.yml
  - type: Overlay
    url: overlays/kickbox-batch-api-overlay.yaml
  - type: Webhooks
    name: Batch verification completion callback
    url: asyncapi/kickbox-batch-webhooks.yml
  - type: APIReference
    url: https://docs.kickbox.com/docs/batch-verification-api
- aid: kickbox:kickbox-open-api
  name: Kickbox Open API
  description: Free disposable-domain lookup (no auth).
  baseURL: https://open.kickbox.com/v1
  humanURL: https://docs.kickbox.com/reference/disposable-email-check
  tags:
  - Open
  properties:
  - type: OpenAPI
    url: openapi/kickbox-open-api-openapi.yml
  - type: Overlay
    url: overlays/kickbox-open-api-overlay.yaml
  - type: APIReference
    url: https://docs.kickbox.com/reference/disposable-email-check
- aid: kickbox:kickbox-verification-api
  name: Kickbox Verification API
  description: Real-time email verification.
  humanURL: https://docs.kickbox.com
  baseURL: https://api.kickbox.com/v2
  tags:
  - Verification
  properties:
  - type: OpenAPI
    url: openapi/kickbox-verification-api-openapi.yml
  - type: Overlay
    url: overlays/kickbox-verification-api-overlay.yaml
  - type: APIReference
    url: https://docs.kickbox.com/docs/single-verification-api
- aid: kickbox:kickbox-disposable-api
  name: Kickbox Disposable API
  description: The Disposable API from Kickbox — 1 operation(s) for disposable.
  humanURL: https://docs.kickbox.com
  baseURL: https://api.kickbox.com/v2
  tags:
  - Disposable
  properties:
  - type: OpenAPI
    url: openapi/kickbox-disposable-api-openapi.yml
common:
- type: AgenticAccess
  url: agentic-access/kickbox-agentic-access.yml
- type: DomainSecurity
  url: security/kickbox-domain-security.yml
- type: Authentication
  url: authentication/kickbox-authentication.yml
- type: LinkedIn
  url: https://www.linkedin.com/company/kickbox
- type: Website
  url: https://kickbox.com
- type: Documentation
  url: https://docs.kickbox.com
- type: Pricing
  url: https://kickbox.com/pricing
- type: SignUp
  url: https://app.kickbox.com/signup
- type: GitHubOrganization
  url: https://github.com/kickboxio
- type: Support
  url: https://articles.kickbox.com/en/collections/1840339-kickbox-help-articles
- type: HelpCenter
  url: https://articles.kickbox.com/en/collections/1840339-kickbox-help-articles
- type: Contact
  url: https://kickbox.com/contact/
- type: LlmsText
  url: https://docs.kickbox.com/llms.txt
- type: LLMsTxt
  name: llms.txt (harvested verbatim from docs.kickbox.com)
  url: llms/kickbox-llms.txt
- type: Blog
  url: https://blog.kickbox.com
- type: BlogRSS
  url: https://blog.kickbox.com/rss/
- type: DeveloperPortal
  url: https://kickbox.com/kickbox-for-developers/
- type: APIReference
  url: https://docs.kickbox.com/docs/single-verification-api
- type: GettingStarted
  url: https://docs.kickbox.com/docs/using-the-api
- type: TermsOfService
  url: https://docs.kickbox.com/docs/terms-of-service
- type: PrivacyPolicy
  url: https://docs.kickbox.com/docs/privacy-policy
- type: Packages
  url: packages/kickbox-packages.yml
- type: SDKs
  name: Official Kickbox client libraries (Node.js, PHP, Python, Ruby)
  url: packages/kickbox-packages.yml
- type: MCPServer
  name: Kickbox documentation MCP server (auth-gated)
  url: mcp/kickbox-mcp.yml
- type: ToolCrosswalk
  url: mcp/kickbox-tool-crosswalk.yml
- type: Sandbox
  url: sandbox/kickbox-sandbox.yml
- type: Conventions
  url: conventions/kickbox-conventions.yml
- type: ErrorCatalog
  url: errors/kickbox-problem-types.yml
- type: Lifecycle
  url: lifecycle/kickbox-lifecycle.yml
- type: StatusPage
  url: https://status.kickbox.com/
- type: DataModel
  url: data-model/kickbox-data-model.yml
- type: Conformance
  url: conformance/kickbox-conformance.yml
- type: TrustCenter
  url: https://trust.kickbox.com/
- type: Compliance
  url: https://docs.kickbox.com/docs/security-and-compliance
- type: Webhooks
  name: Batch verification completion callback
  url: asyncapi/kickbox-batch-webhooks.yml
- type: AgentSkill
  url: skills/_index.yml
- type: Plans
  url: plans/kickbox-plans-pricing.yml
- type: RateLimits
  url: rate-limits/kickbox-rate-limits.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
x-enrichment:
  date: '2026-08-13'
  status: enriched
  artifacts_added: 24
  pass: local-v1

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