lenz-io

Lenz provides an audit‑grade AI fact‑checking API that verifies factual claims in AI‑generated or human‑written text against independent sources. It offers a multi‑model verification pipeline, reviewer panels, and detailed source citations to ensure trustworthy outputs. The service includes a free trial, tiered pricing, and integrations with major AI models like Claude and ChatGPT, targeting enterprises needing reliable AI content validation.

lenz-io publishes 11 API contracts indexed on the APIs.io network, including Account API, Ask API, Assess API, and 8 more. Tagged areas include AI, Fact-Checking, Enterprise, API, and Audit.

The lenz-io catalog on APIs.io includes 1 event-driven AsyncAPI specification, 1 JSON-LD context, and 1 Spectral governance ruleset.

lenz-io’s developer surface includes CLI, authentication, documentation, API reference, getting-started guide, pricing, and 20 more developer resources.

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61.5/100 strong Agent 49/100 agent ready Full breakdown ↓
scored 2026-10-31 · rubric v0.25.0 · Show this score on your site →

1 published contract 2 Agent Skills

AIFact-CheckingEnterpriseAPIAudit

Kin Score

Kin Score How this is scored →
scored 2026-10-31 · rubric v0.25.0

Composite quality — 61.5/100 · strong

Contract Quality 13.1 / 21

Developer Ergonomics 10.4 / 17

Access Clarity 10.2 / 17

Operational Transparency 3.5 / 11

Contract Governance 8.1 / 10

Discoverability 4.9 / 9

Regulatory Posture 4.8 / 15

Agent readiness — 49/100 · 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 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 3 / 3

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 could not be measured. We hold no machine-readable contract for this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero: never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and several others — scorable at all.

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/.

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

Idempotency +9 pts — OpenAPI mutating operations declare an idempotency key — a header, a request-body property, or a named de-duplication token whose own description says so (verified); else common[].type matches /idempoten/i (documented)
A2A Agent Card +8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0
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)
Registration Without a Human +6 pts — a `registration_endpoint` in the served RFC 8414 / OIDC discovery document
Documented Reversibility +6 pts — a reversal operation in the contract, graded up when a window is documented too
Agentic Commerce Well-Known Document +5 pts — a parsing /.well-known/ucp.json or acp.json declaring a version and at least one service — `self` when its endpoints are on the provider's own domain, `platform` when they are on a vendor's

3 more unmet checks in the Agent Readiness table above.

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

Contract Quality scores 61.5 — up to +9.6 composite points
Operational Transparency scores 32.1 — up to +8.8 composite points
Access Clarity scores 60.0 — up to +8.0 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/lenz-io/apis.yml: open an issue on github.com/api-evangelist/lenz-io 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 →

APIs 11

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

lenz-io Account API

Your credit balance, the price list, and rate-limit usage.

lenz-io Ask API

Ask follow-up questions grounded on an existing verification.

lenz-io Assess API

Fast panel verdict on a claim, with the pages the reviewers looked at. Sync, typically 10-25s; allow 45s for the response.

lenz-io Citecheck API

Check whether each cited source says what a draft attributes to it: from a draft with its links, or from statement-source pairs. Async; 1 credit per checked citation, and a sour...

lenz-io Discovery API

Machine-readable index of the API root.

lenz-io Extract API

Pull verifiable claims out of any text. Costs no credits; fair-use cap 1,000/account/day.

lenz-io Lenz — AI Fact Checking API

The Lenz — AI Fact Checking API API from lenz-io — 0 operation(s) for lenz — ai fact checking api.

lenz-io Library API

Browse the public catalog of verifications. No API key required.

lenz-io Review API

The whole recipe in one call: find the claims in a draft, quick-check each, deep-check the ones that look wrong or uncertain, and get the issues back with suggested rewrites. As...

lenz-io Verifications API

List, fetch, delete, and toggle visibility on stored verifications.

lenz-io Verify API

The full investigation, with verified citations. Async, ~90s. Submit one claim or a batch, poll status, and resolve a needs_input interrupt with select.

Scroll for all 11

Agent Skills 2

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

assessment

AGENT SKILL

lenz-io-review-skill

AGENT SKILL

Pricing Plans 1

Published pricing tiers and plan structures.

Lenz Io Plans Pricing

5 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Lenz Io Rate Limits

1 limits

RATE LIMITS

Event Specifications 1

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

Lenz Io Webhooks

ASYNCAPI

Semantic Vocabularies 1

JSON-LD contexts and semantic vocabularies used across these APIs.

Lenz Io Context

120 classes · 252 properties

JSON-LD

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

lenz-io API Rules

15 rules · 13 errors 1 warnings 1 info

SPECTRAL

JSON Schema 6

Standalone JSON Schema definitions for this provider's data models.

ClaimDetailOutLegacy

20 properties

JSON SCHEMA

ClaimDetailOut

20 properties

JSON SCHEMA

ReviewFullOutLegacy

21 properties

JSON SCHEMA

ReviewFullOut

21 properties

JSON SCHEMA

ReviewIssuesOutLegacy

19 properties

JSON SCHEMA

ReviewIssuesOut

19 properties

JSON SCHEMA

Security Posture 2

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

Lenz Io Authentication

1 scheme

SECURITY

Lenz Io Domain Security

TLSv1.3 · DMARC

SECURITY

Scopes 1

OAuth scopes governing access to this provider's APIs.

Lenz Io Scopes

OAuth 2.0 · no documented scopes

0 scopes

SCOPES

Agentic Access 1

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

Lenz Io Agentic Access

24 operations · 13 acting · 1 human-in-the-loop

24 operations · 13 acting

AGENTIC

Resources

Get Started 1

Portal, sign-up, and the first successful call

GettingStarted

GettingStarted

Documentation 2

Reference material describing how the API behaves

Documentation

Documentation

APIReference

APIReference

Agent Surfaces 4

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgentSkill

LLMsTxt

WellKnown

Design & Contract 7

Pagination, idempotency, versioning, errors, and events

Spectral

JSONLD

Vocabulary

Webhooks

DataModel

ErrorCatalog

Conformance

Scroll for all 7

Build 4

SDKs, sample code, and the tooling you integrate with

CLI

CLI

SDKs

SDKs

Packages

Packages

GitHubOrganization

GitHubOrganization

Access & Security 2

Authentication, authorization, and security posture

Authentication

Authentication

DomainSecurity

DomainSecurity

Commercial 4

Pricing, plans, and the legal terms of use

Plans

Pricing

TermsOfService

PrivacyPolicy

Company 1

The organization behind the API

Website

Website

Other 1

Properties that don't map to a standard resource type

Hosts

Hosts

Source (apis.yml)

aid: lenz-io
name: lenz-io
image: https://lenz.io/media/og-image.png?v=9
description: Lenz provides an audit‑grade AI fact‑checking API that verifies factual claims in AI‑generated or human‑written
  text against independent sources. It offers a multi‑model verification pipeline, reviewer panels, and detailed source citations
  to ensure trustworthy outputs. The service includes a free trial, tiered pricing, and integrations with major AI models
  like Claude and ChatGPT, targeting enterprises needing reliable AI content validation.
url: https://artifacts.apis.io/lenz-io/apis.yml
x-type: company
x-source: harvest:mcp-registry
x-tier: profiled
x-tier-reason: enrichment pass 2026-10-30 (modular-v1; was harvest)
specificationVersion: '0.20'
created: '2026-10-30'
modified: '2026-10-30'
tags:
- AI
- Fact-Checking
- Enterprise
- API
- Audit
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: AgenticAccess
  url: agentic-access/lenz-io-agentic-access.yml
- type: Plans
  url: plans/lenz-io-plans-pricing.yml
- type: Spectral
  url: rules/lenz-io-rules.yml
- type: JSONLD
  url: json-ld/lenz-io-context.jsonld
- type: Vocabulary
  url: vocabulary/lenz-io-vocabulary.yml
- type: AgentSkill
  url: skills/_index.yml
- type: Webhooks
  url: asyncapi/lenz-io-webhooks.yml
- type: DataModel
  url: data-model/lenz-io-data-model.yml
- type: CLI
  url: cli/lenz-io-cli.yml
- type: Authentication
  url: authentication/lenz-io-authentication.yml
- type: ErrorCatalog
  url: errors/lenz-io-problem-types.yml
- type: Conformance
  url: conformance/lenz-io-conformance.yml
- type: LLMsTxt
  url: llms/lenz-io-llms.txt
- type: WellKnown
  url: well-known/lenz-io-well-known.yml
- type: Hosts
  url: hosts/lenz-io-hosts.yml
- type: SDKs
  url: packages/lenz-io-packages.yml
- type: Packages
  url: packages/lenz-io-packages.yml
- type: GitHubOrganization
  url: https://github.com/lenzhq
- type: DomainSecurity
  url: security/lenz-io-domain-security.yml
- type: Website
  url: https://lenz.io/
- type: Documentation
  url: https://lenz.io/developers
- type: APIReference
  url: https://lenz.io/api/v1/docs/
- type: GettingStarted
  url: https://lenz.io/docs/quickstart
- type: Pricing
  url: https://lenz.io/plans
- type: TermsOfService
  url: https://lenz.io/terms
- type: PrivacyPolicy
  url: https://lenz.io/privacy
apis:
- aid: lenz-io:lenz-io-account-api
  name: lenz-io Account API
  description: Your credit balance, the price list, and rate-limit usage.
  baseURL: https://lenz.io
  tags:
  - Account
  properties:
  - type: OpenAPI
    url: openapi/lenz-io-account-api-openapi.yml
- aid: lenz-io:lenz-io-ask-api
  name: lenz-io Ask API
  description: Ask follow-up questions grounded on an existing verification.
  baseURL: https://lenz.io
  tags:
  - Ask
  properties:
  - type: OpenAPI
    url: openapi/lenz-io-ask-api-openapi.yml
- aid: lenz-io:lenz-io-assess-api
  name: lenz-io Assess API
  description: Fast panel verdict on a claim, with the pages the reviewers looked at. Sync, typically 10-25s; allow 45s for
    the response.
  baseURL: https://lenz.io
  tags:
  - Assess
  properties:
  - type: OpenAPI
    url: openapi/lenz-io-assess-api-openapi.yml
- aid: lenz-io:lenz-io-citecheck-api
  name: lenz-io Citecheck API
  description: 'Check whether each cited source says what a draft attributes to it: from a draft with its links, or from statement-source
    pairs. Async; 1 credit per checked citation, and a source that could not be checked is not charged.'
  baseURL: https://lenz.io
  tags:
  - Citecheck
  properties:
  - type: OpenAPI
    url: openapi/lenz-io-citecheck-api-openapi.yml
- aid: lenz-io:lenz-io-discovery-api
  name: lenz-io Discovery API
  description: Machine-readable index of the API root.
  baseURL: https://lenz.io
  tags:
  - Discovery
  properties:
  - type: OpenAPI
    url: openapi/lenz-io-discovery-api-openapi.yml
- aid: lenz-io:lenz-io-extract-api
  name: lenz-io Extract API
  description: Pull verifiable claims out of any text. Costs no credits; fair-use cap 1,000/account/day.
  baseURL: https://lenz.io
  tags:
  - Extract
  properties:
  - type: OpenAPI
    url: openapi/lenz-io-extract-api-openapi.yml
- aid: lenz-io:lenz-io-lenz-ai-fact-checking-api-api
  name: lenz-io Lenz — AI Fact Checking API
  description: The Lenz — AI Fact Checking API API from lenz-io — 0 operation(s) for lenz — ai fact checking api.
  baseURL: https://lenz.io
  tags:
  - Lenz — AI Fact Checking API
  properties:
  - type: OpenAPI
    url: openapi/lenz-io-lenz-ai-fact-checking-api-api-openapi.yml
- aid: lenz-io:lenz-io-library-api
  name: lenz-io Library API
  description: Browse the public catalog of verifications. No API key required.
  baseURL: https://lenz.io
  tags:
  - Library
  properties:
  - type: OpenAPI
    url: openapi/lenz-io-library-api-openapi.yml
- aid: lenz-io:lenz-io-review-api
  name: lenz-io Review API
  description: 'The whole recipe in one call: find the claims in a draft, quick-check each, deep-check the ones that look
    wrong or uncertain, and get the issues back with suggested rewrites. Async, two to four minutes; poll the review or receive
    review.completed at a webhook.'
  baseURL: https://lenz.io
  tags:
  - Review
  properties:
  - type: OpenAPI
    url: openapi/lenz-io-review-api-openapi.yml
- aid: lenz-io:lenz-io-verifications-api
  name: lenz-io Verifications API
  description: List, fetch, delete, and toggle visibility on stored verifications.
  baseURL: https://lenz.io
  tags:
  - Verifications
  properties:
  - type: OpenAPI
    url: openapi/lenz-io-verifications-api-openapi.yml
- aid: lenz-io:lenz-io-verify-api
  name: lenz-io Verify API
  description: The full investigation, with verified citations. Async, ~90s. Submit one claim or a batch, poll status, and
    resolve a needs_input interrupt with select.
  baseURL: https://lenz.io
  tags:
  - Verify
  properties:
  - type: OpenAPI
    url: openapi/lenz-io-verify-api-openapi.yml
x-coverage:
  state: gated
  reason: partner-login
  method: derived
  generated: '2026-10-30'
  generator: derive-coverage.py (pre-flight evidence)
  detail: the company serves an API surface but requires credentials before any description of it can be read
  evidence:
  - url: https://lenz.io/mcp
    status: 401
  - url: https://lenz.io/
    status: 200
x-enrichment:
  date: '2026-10-30'
  status: enriched
  artifacts_added: 27
  pass: modular-v1
  engine: identity=local,contract=local,surfaces=local,docs=local,regulatory=local

lenz-io API — frequently asked questions

Does lenz-io have an API?

Yes. APIs.io lists 11 APIs from lenz-io, including lenz-io Account API, lenz-io Ask API and lenz-io Assess API, and 8 more.

Is there an OpenAPI specification for the lenz-io API?

Yes. APIs.io indexes 11 OpenAPI specifications for lenz-io, each linked for download from this page.

How do I authenticate with the lenz-io API?

lenz-io uses bearer-token authentication (1 scheme). The details are profiled on APIs.io as Lenz Io Authentication.

How much does the lenz-io API cost?

APIs.io lists 5 pricing plans for lenz-io, with each plan's price, limits and inclusions under Pricing Plans on this page.

Is the lenz-io API ready for AI agents?

lenz-io has a Kin Score of 61.5 out of 100 (strong) and an Agent Readiness score of 48.8 (agent-ready), scored by API Evangelist on 2026-10-31.

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