uChecker

Russian-language email-validation platform offering bulk and single email verification (SMTP mailbox existence, MX/DNS, catch-all, disposable, role-based, spam-trap/blacklist checks) plus free DNS/email tools. Access via REST API, a hosted MCP server, web dashboard, and Telegram bot.

uChecker publishes 3 API contracts indexed on the APIs.io network: Аутентификация API, Валидация Email API, and ESP Провайдеры API. Tagged areas include Email Verification, Email, SMTP, DNS, and Deliverability.

The uChecker catalog on APIs.io includes 1 event-driven AsyncAPI specification and 1 Spectral governance ruleset.

uChecker’s developer surface includes authentication, developer console, API reference, documentation, pricing, signup flow, support, and 21 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

51.0/100 developing ▬ flat Agent 44/100 agent native Front door AI 1/6 silent Heartbeat 62/100 slowing saas Full breakdown ↓
scored 2026-11-06 · rubric v0.27.0 · Show this score on your site →

AccessFreemiumSelf serve⚡ Free to try

1 published contract 1 MCP Servers 3 Agent Skills

Email Verification Email SMTP DNS DeliverabilitymxSPF DKIM DMARC MCP Agent-Native Data Quality

What this lets a business do 1

Business capabilities this provider's published APIs can perform, derived from its own contracts. Browse all capabilities →

Information & Data Management

BC-610

Валидация Email

POST /api/v1/validate/single POST /api/v1/validate/bulk GET /api/v1/tasks/{taskId} GET /api/v1/tasks/{taskId}/analytics

Kin Score

Kin Score How this is scored →
scored 2026-11-06 · rubric v0.27.0

Composite quality — 51.0/100 · developing

Contract Quality 10.3 / 19

Developer Ergonomics 6.7 / 15

Access Clarity 10.7 / 15

Operational Transparency 0.8 / 10

Contract Governance 1.6 / 9

Discoverability 5.6 / 8

Regulatory Posture 3.7 / 15

Create-or-Update Ergonomics 2.8 / 10

Agent readiness — 44/100 · agent native

Machine-Readable Contract 18 / 18

Agentic Access Contract 0 / 10

Documented Reversibility 6 / 6

MCP Server 12 / 12

Machine-Readable Auth 10 / 10

Idempotency 9 / 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

Pagination 5 / 5

Distinct Operations 0 / 3

MCP Tool Quality 6 / 6

Regulatory Posture applies to this provider. Its tags matched the Horizontal (data, software, accessibility, platform) 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.

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.

The six quality facets above are damped to 75 points between them, because the conditional facet above carries the other 25. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 75% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.

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Agent readiness — checks not met, largest first (exact, from this profile):

Agentic Access Contract +10 pts — agentic_access artifact present (x-agentic-access), graded by author
A2A Agent Card +8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0
Registration Without a Human +6 pts — a `registration_endpoint` in the served RFC 8414 / OIDC discovery document
Delegated User Identity +6 pts — a served discovery document listing authorization_code in grant_types_supported (served), else an oauth2 authorizationCode flow or openIdConnect declared in an OpenAPI (documented)
Protected Resource Metadata +5 pts — a served /.well-known/oauth-protected-resource carrying `resource` (documented), and naming its authorization_servers (verified)
Agentic Commerce Well-Known Document +5 pts — a parsing /.well-known/ucp.json or acp.json declaring a version and at least one service, OR (0.27) a live x402 payment challenge from _data/x402-adoption.json — `self` when its endpoints are on the provider's own domain, `platform` when they are on a vendor's

4 more unmet checks in the Agent Readiness table above.

Kin Score — facets with the most composite points still available (weight × headroom):

Operational Transparency scores 7.9 — up to +12.0 composite points
Contract Quality scores 54.8 — up to +11.3 composite points
Developer Ergonomics scores 44.6 — up to +11.1 composite points

Each check links to what satisfies it. Publish the artifact, or tell us where it already lives, and the score moves on the next scoring run.

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 the provider profile at artifacts.apis.io/uchecker/apis.yml: open an issue on github.com/api-evangelist/uchecker to ask a question or point us at an artifact you publish. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

Standards implemented 4

Standards this provider implements or carries. De facto ones are profiled and measured by the API Commons; formal ones come from the standards directory and are linked by the provider's own tags. The evidence column says how each claim was established — not that it was made.

DNS

tagged — the provider's own APIs.json carries the standard as a tag; implementation not verified

Model Context Protocol (MCP)

measured — observed by APIs.io (verified)

SMTP

tagged — the provider's own APIs.json carries the standard as a tag; implementation not verified

OpenAPI

measured — observed by APIs.io (published)

APIs 3

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

uChecker Аутентификация API

Вход, регистрация, управление JWT-токенами и API ключами, привязка Telegram

uChecker Валидация Email API

Проверка email-адресов, управление задачами валидации, получение и скачивание результатов

uChecker ESP Провайдеры API

Программный интерфейс для ESP-провайдеров: расчёт стоимости и автоматическое создание аккаунтов с зачислением кредитов

MCP Servers 1

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

uChecker MCP Server

MCP SERVER

Agent Skills 3

Packaged agent skills for driving this provider's APIs from an AI assistant.

Audit credit spend and job history

AGENT SKILL

Clean a mailing list in bulk

AGENT SKILL

Validate a single email address

AGENT SKILL

uChecker API pricing

Prices published by uChecker, read 2026-10-28 from uchecker.net/en#tariffs.

Plan	Price
First 100 addresses free	First 100 addresses free Includes: 100 addresses
1,000 addresses	$3 Includes: $3 per 1,000
5,000 addresses	$13 Includes: $2.60 per 1,000
10,000 addresses	$25 Includes: $2.50 per 1,000
25,000 addresses	$47 Includes: $1.88 per 1,000
50,000 addresses	$94 Includes: $1.88 per 1,000
100,000 addresses	$187 Includes: $1.87 per 1,000
200,000 addresses	$199 Includes: $1.00 per 1,000

All 11 plans, limits and sources →

Billed by: addresses · FinOps profile →

Pricing Plans 1

Published pricing tiers and plan structures.

Uchecker Plans Pricing

11 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Uchecker Rate Limits

0 limits

RATE LIMITS

Service Levels 1

Uptime the provider promises or reports, as SLA4OAI. Read from its own pages; APIs.io runs no monitors.

uChecker

SLA

FinOps 1

Cost, billing, and metering signals for API financial operations.

Uchecker Finops

FINOPS

Event Specifications 1

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

Uchecker Webhooks

ASYNCAPI

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

uChecker API Rules

53 rules · 44 errors 7 warnings 2 info

SPECTRAL

OpenAPI Overlays 3

Overlays applied on top of this provider's contracts. Each card says who wrote it: a document the provider publishes, or one API Evangelist derived or generated.

Uchecker Default Api Overlay

5 actions · update · uchecker-default-api-openapi.yml

GENERATED

Uchecker Email Api Overlay

6 actions · update · uchecker-email-api-openapi.yml

GENERATED

Uchecker Esp Api Overlay

3 actions · update · uchecker-esp-api-openapi.yml

GENERATED

Security Posture 2

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

Uchecker Authentication

apiKey/http · 3 schemes

SECURITY

Uchecker Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Resources

Get Started 2

Portal, sign-up, and the first successful call

Console

Console

SignUp

SignUp

Documentation 2

Reference material describing how the API behaves

APIReference

APIReference

Documentation

Documentation

Agent Surfaces 4

MCP servers, agent skills, and machine-readable catalogs

MCPServer

MCPServer

AgentSkill

LLMsTxt

Design & Contract 7

Pagination, idempotency, versioning, errors, and events

Conventions

Idempotency

ErrorCatalog

Webhooks

DataModel

Conformance

Lifecycle

Scroll for all 7

Build 2

SDKs, sample code, and the tooling you integrate with

ToolCrosswalk

ToolCrosswalk

Packages

Packages

Access & Security 2

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Authentication

Authentication

Operate 2

Status, limits, changes, and where to get help

RateLimits

RateLimits

Support

Support

Commercial 4

Pricing, plans, and the legal terms of use

Plans

Pricing

TermsOfService

PrivacyPolicy

Company 2

The organization behind the API

Website

Website

Blog

Blog

Other 1

Properties that don't map to a standard resource type

CapabilityMap

CapabilityMap

Source (apis.yml)

name: uChecker
description: Russian-language email-validation platform offering bulk and single email verification (SMTP mailbox existence,
  MX/DNS, catch-all, disposable, role-based, spam-trap/blacklist checks) plus free DNS/email tools. Access via REST API, a
  hosted MCP server, web dashboard, and Telegram bot.
url: https://raw.githubusercontent.com/api-evangelist/uchecker/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: freemium
  onboarding: self-serve
  trial: false
  try_now: true
  public: false
  gated: none
  gated_source:
  - onboarding
  label: Freemium · Self-serve signup
  confidence: high
  source:
  - plans
  - authentication
  - rate-limits
  - security
  - sandbox
  generated: '2026-11-06'
  method: derived
image: https://uchecker.net/images/og-image.png
created: '2026-08-16'
modified: '2026-08-16'
specificationVersion: '0.23'
tags:
- Email Verification
- Email
- SMTP
- DNS
- Deliverability
- mx
- SPF
- DKIM
- DMARC
- MCP
- Agent-Native
- Data Quality
tags_raw:
- email-verification
- email
- smtp
- dns
- deliverability
- mx
- spf
- dkim
- dmarc
- mcp
- agent-native
- data-quality
apis:
- aid: uchecker:uchecker-default-api
  name: uChecker Аутентификация API
  description: Вход, регистрация, управление JWT-токенами и API ключами, привязка Telegram
  humanURL: https://api.uchecker.net/docs
  baseURL: https://api.uchecker.net
  tags: []
  tags_raw:
  - Аутентификация
  properties:
  - type: OpenAPI
    url: openapi/uchecker-default-api-openapi.yml
  - type: Overlay
    url: overlays/uchecker-default-api-overlay.yaml
  - type: Documentation
    url: https://api.uchecker.net/docs
  - type: Documentation
    url: https://uchecker.net/mcp
- aid: uchecker:uchecker-email-api
  name: uChecker Валидация Email API
  description: Проверка email-адресов, управление задачами валидации, получение и скачивание результатов
  humanURL: https://api.uchecker.net/docs
  baseURL: https://api.uchecker.net
  tags:
  - Email
  tags_raw:
  - Валидация Email
  properties:
  - type: OpenAPI
    url: openapi/uchecker-email-api-openapi.yml
  - type: Overlay
    url: overlays/uchecker-email-api-overlay.yaml
  - type: Documentation
    url: https://api.uchecker.net/docs
  - type: Documentation
    url: https://uchecker.net/mcp
- aid: uchecker:uchecker-esp-api
  name: uChecker ESP Провайдеры API
  description: 'Программный интерфейс для ESP-провайдеров: расчёт стоимости и автоматическое создание аккаунтов с зачислением
    кредитов'
  humanURL: https://api.uchecker.net/docs
  baseURL: https://api.uchecker.net
  tags:
  - ESP Провайдеры
  properties:
  - type: OpenAPI
    url: openapi/uchecker-esp-api-openapi.yml
  - type: Overlay
    url: overlays/uchecker-esp-api-overlay.yaml
  - type: Documentation
    url: https://api.uchecker.net/docs
  - type: Documentation
    url: https://uchecker.net/mcp
maintainers:
- FN: uChecker
  email: support@uchecker.net
  url: https://uchecker.net
generated:
  by: apis.io/add
  model: claude-opus-4-8
  confidence: 95
  at: '2026-08-16T17:52:03.735Z'
common:
- type: Website
  url: https://www.uchecker.net/
- type: CapabilityMap
  url: capabilities/uchecker-capability-edges.yml
  name: uChecker Business Capability Map
- type: DomainSecurity
  url: security/uchecker-domain-security.yml
- type: Authentication
  url: authentication/uchecker-authentication.yml
- type: MCPServer
  url: https://api.uchecker.net/mcp
- type: MCPServer
  url: mcp/uchecker-mcp.yml
- type: ToolCrosswalk
  url: mcp/uchecker-tool-crosswalk.yml
- type: AgentSkill
  url: skills/_index.yml
- type: LLMsTxt
  url: llms/uchecker-llms.txt
- type: Conventions
  url: conventions/uchecker-conventions.yml
- type: Idempotency
  url: conventions/uchecker-conventions.yml
- type: ErrorCatalog
  url: errors/uchecker-problem-types.yml
- type: Webhooks
  url: asyncapi/uchecker-webhooks.yml
- type: DataModel
  url: data-model/uchecker-data-model.yml
- type: Conformance
  url: conformance/uchecker-conformance.yml
- type: Lifecycle
  url: lifecycle/uchecker-lifecycle.yml
- type: RateLimits
  url: rate-limits/uchecker-rate-limits.yml
- type: Plans
  url: plans/uchecker-plans-pricing.yml
- type: Packages
  url: packages/uchecker-packages.yml
- type: Console
  url: https://api.uchecker.net/docs
- type: APIReference
  url: https://api.uchecker.net/docs
- type: Documentation
  url: https://api.uchecker.net/docs
- type: Pricing
  url: https://uchecker.net/en#tariffs
- type: SignUp
  url: https://app.uchecker.net
- type: Support
  url: https://t.me/goodsam911
- type: Blog
  url: https://uchecker.net/blog-en
- type: TermsOfService
  url: https://uchecker.net/terms-of-service
- type: PrivacyPolicy
  url: https://uchecker.net/privacy-policy
x-enrichment:
  date: '2026-08-16'
  status: enriched
  artifacts_added: 23
  pass: local-v1

uChecker API — frequently asked questions

Does uChecker have an API?

Yes. APIs.io lists 3 APIs from uChecker, including uChecker Аутентификация API, uChecker Валидация Email API and uChecker ESP Провайдеры API.

Is there an OpenAPI specification for the uChecker API?

Yes. APIs.io indexes 3 OpenAPI specifications for uChecker, each linked for download from this page.

How do I authenticate with the uChecker API?

uChecker uses bearer-token authentication (apiKey/http · 3 schemes). The details are profiled on APIs.io as Uchecker Authentication.

How much does the uChecker API cost?

uChecker publishes its prices; its First 100 addresses free plan is First 100 addresses free as of 2026-10-28. APIs.io lists 11 pricing plans for uChecker, with each plan's price, limits and inclusions under Pricing on this page.

Does uChecker have an MCP server?

Yes. APIs.io lists 1 MCP server for uChecker.

Is the uChecker API ready for AI agents?

uChecker has a Kin Score of 51.0 out of 100 (developing) and an Agent Readiness score of 44.3 (agent-native), scored by API Evangelist on 2026-11-06.

Work with this as data

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