Lang.ai

Lang.ai is a conversation-intelligence platform that turns unstructured customer interactions — support tickets, chatbot messages, emails and calls — into structured intents, features and tags. Its unsupervised algorithm ingests a dataset of customer text, automatically extracts the intents and features it finds, and lets teams group those into tags that form a custom classifier for any language, industry or business case. A small REST API then applies that classifier in real time: create a project from a CSV dataset, list projects and their tags, analyze a document to get back its matched tags and intents, and save documents with arbitrary metadata for dashboard reporting. Lang.ai was founded in Spain, backed by 500 Global, and is now part of Capacity, whose AI support-automation platform absorbed Lang.ai's conversation intelligence.

Lang.ai publishes 2 APIs on the APIs.io network: Documents API and Projects API. Tagged areas include Company, Artificial Intelligence, Machine-Learning, Natural Language Processing, and Conversation Intelligence.

Lang.ai’s developer surface includes documentation, API reference, getting-started guide, support, engineering blog, pricing, signup flow, and 30 more developer resources.

🌐 Visit website 📡 Source on GitHub

46.1/100 developing ▬ flat Agent 32/100 agent ready Front door AI 6/6 dominant saas Full breakdown ↓
scored 2026-09-19 · rubric v0.22.0

AccessPaid

2 APIs

Company Artificial Intelligence Machine-Learning Natural Language Processing Conversation Intelligence Customer-Support Text Classification Analytics Customer Experience

Kin Score

Kin Score How this is scored →
scored 2026-09-19 · rubric v0.22.0

Composite quality — 46.1/100 · developing

Contract Quality 4.1 / 23

Developer Ergonomics 9.5 / 18

Access Clarity 16.6 / 18

Operational Transparency 4.6 / 12

Contract Governance 0.5 / 11

Discoverability 6.8 / 9

Create-or-Update Ergonomics 0.0 / 10

Agent readiness — 32/100 · agent ready

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 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 0 / 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/langai: 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 2

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

Lang.ai Documents API

Analyze and save documents against a project.

Lang.ai Projects API

Create and inspect classification projects and their tags.

Open Collections 3

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

API Collection

OPEN COLLECTION

Lang.ai Documents API

OPEN COLLECTION

Lang.ai Documents Projects API

OPEN COLLECTION

Pricing Plans 1

Published pricing tiers and plan structures.

Langai Plans Pricing

3 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Langai Rate Limits

0 limits

RATE LIMITS

Security Posture 4

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

Langai Authentication

http · 1 scheme

SECURITY

Langai Domain Security

TLSv1.2 · DMARC

SECURITY

Langai Vulnerability Disclosure

Hackerone · security.txt · contact published

SECURITY

Langai Trust Center

SOC 2 Type II, HIPAA, GDPR

SECURITY

Agentic Access 1

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

Langai Agentic Access

5 operations · 3 acting

AGENTIC

Resources

Get Started 3

Portal, sign-up, and the first successful call

DeveloperPortal

DeveloperPortal

GettingStarted

GettingStarted

SignUp

SignUp

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

AgenticAccess

X-MCPServerCandidate

X-MCPServerCandidate

LLMsTxt

LLMsTxt

AgentSkill

AgentSkill

Design & Contract 6

Pagination, idempotency, versioning, errors, and events

Conventions

Idempotency

ErrorCatalog

Lifecycle

Conformance

DataModel

Build 3

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

Examples

Examples

Packages

Packages

Access & Security 5

Authentication, authorization, and security posture

Compliance

Compliance

Authentication

Authentication

DomainSecurity

DomainSecurity

VulnerabilityDisclosure

VulnerabilityDisclosure

TrustCenter

TrustCenter

Operate 7

Status, limits, changes, and where to get help

Support

HelpCenter

StatusPage

ChangeLog

ChangeLog

Roadmap

RateLimits

Scroll for all 7

Commercial 4

Pricing, plans, and the legal terms of use

Pricing

TermsOfService

PrivacyPolicy

Plans

Company 2

The organization behind the API

Website

Website

Blog

Blog

Other 1

Properties that don't map to a standard resource type

Overlay

Overlay

Source (apis.yml)

aid: langai
name: Lang.ai
description: 'Lang.ai is a conversation-intelligence platform that turns unstructured customer interactions — support tickets,
  chatbot messages, emails and calls — into structured intents, features and tags. Its unsupervised algorithm ingests a dataset
  of customer text, automatically extracts the intents and features it finds, and lets teams group those into tags that form
  a custom classifier for any language, industry or business case. A small REST API then applies that classifier in real time:
  create a project from a CSV dataset, list projects and their tags, analyze a document to get back its matched tags and intents,
  and save documents with arbitrary metadata for dashboard reporting. Lang.ai was founded in Spain, backed by 500 Global,
  and is now part of Capacity, whose AI support-automation platform absorbed Lang.ai''s conversation intelligence.'
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: paid
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Paid
  confidence: high
  source:
  - plans
  - authentication
  - rate-limits
  - security
  - sandbox
  - url: https://lang.ai
    status: 301
    note: declared website redirects to https://capacity.com/lang/?company=lang.ai — a different registrable domain (lang.ai
      -> capacity.com), possible rename or acquisition (probed 2026-09-03, roadmap#169)
  generated: '2026-09-03'
  method: derived
image: https://docs.lang.ai/images/logo-lang.svg
url: https://raw.githubusercontent.com/api-evangelist/langai/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- 500-global
x-tier: enriched
x-tier-reason: documented-rest-api
x-status: acquired
x-acquired-by: Capacity
x-acquisition-note: lang.ai now redirects to https://capacity.com/lang/ ("Lang AI is now part of Capacity"). The Lang.ai API
  reference at https://docs.lang.ai/ and the help center at https://help.lang.ai/ remain live; commercial, legal, status and
  compliance properties are Capacity's.
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-08-14'
tags:
- Company
- Artificial Intelligence
- Machine-Learning
- Natural Language Processing
- Conversation Intelligence
- Customer-Support
- Text Classification
- Analytics
- Customer Experience
tags_raw:
- Company
- Artificial Intelligence
- Machine Learning
- Natural Language Processing
- Conversation Intelligence
- Customer Support
- Text Classification
- Analytics
- Customer Experience
apis:
- aid: langai:langai-documents-api
  name: Lang.ai Documents API
  description: Analyze and save documents against a project.
  humanURL: https://docs.lang.ai/
  baseURL: https://company.lang.ai/api/v1
  tags:
  - Documents
  properties:
  - type: OpenAPI
    url: openapi/langai-documents-api-openapi.yml
  - type: Documentation
    url: https://docs.lang.ai/
  - type: APIReference
    url: https://docs.lang.ai/
  - type: Authentication
    url: authentication/langai-authentication.yml
  - type: ErrorCatalog
    url: errors/langai-problem-types.yml
  - type: DataModel
    url: data-model/langai-data-model.yml
- aid: langai:langai-projects-api
  name: Lang.ai Projects API
  description: Create and inspect classification projects and their tags.
  humanURL: https://docs.lang.ai/
  baseURL: https://company.lang.ai/api/v1
  tags:
  - Project
  tags_raw:
  - Projects
  properties:
  - type: OpenAPI
    url: openapi/langai-projects-api-openapi.yml
  - type: Documentation
    url: https://docs.lang.ai/
  - type: APIReference
    url: https://docs.lang.ai/
  - type: Authentication
    url: authentication/langai-authentication.yml
  - type: ErrorCatalog
    url: errors/langai-problem-types.yml
  - type: DataModel
    url: data-model/langai-data-model.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: AgenticAccess
  url: agentic-access/langai-agentic-access.yml
- type: Website
  url: https://lang.ai
- type: DeveloperPortal
  url: https://docs.lang.ai/
- type: Documentation
  url: https://docs.lang.ai/
- type: APIReference
  url: https://docs.lang.ai/
- type: GettingStarted
  url: https://docs.lang.ai/#workflow
- type: Support
  url: https://help.lang.ai/
- type: HelpCenter
  url: https://help.lang.ai/
- type: GitHubOrganization
  url: https://github.com/lang-ai
- type: Blog
  url: https://capacity.com/blog/
- type: Pricing
  url: https://capacity.com/pricing/
- type: SignUp
  url: https://capacity.com/lang/
- type: TermsOfService
  url: https://capacity.com/website-terms-of-use/
- type: PrivacyPolicy
  url: https://capacity.com/privacy-policy/
- type: StatusPage
  url: https://status.capacity.com/
- type: Compliance
  url: https://capacity.com/security/
- type: Authentication
  url: authentication/langai-authentication.yml
- type: Conventions
  url: conventions/langai-conventions.yml
- type: Idempotency
  url: conventions/langai-conventions.yml
- type: ErrorCatalog
  url: errors/langai-problem-types.yml
- type: Lifecycle
  url: lifecycle/langai-lifecycle.yml
- type: Conformance
  url: conformance/langai-conformance.yml
- type: DataModel
  url: data-model/langai-data-model.yml
- type: X-MCPServerCandidate
  url: mcp/langai-mcp.yml
  note: 'Renamed from MCPServer 2026-09-03 (roadmap#247): the manifest self-describes as status: candidate — a tool list derived
    from the published API contracts, not an existing server. The scorer already read the manifest and reported mcp_server
    correctly; the MCPServer type was crediting the artifact-type surfaces with a server that does not exist.'
- type: LLMsTxt
  url: llms/langai-llms.txt
- type: AgentSkill
  url: skills/_index.yml
- type: Overlay
  url: overlays/langai-api-overlay.yaml
- type: DomainSecurity
  url: security/langai-domain-security.yml
- type: VulnerabilityDisclosure
  url: security/langai-vulnerability-disclosure.yml
- type: TrustCenter
  url: security/langai-trust-center.yml
- type: ChangeLog
  url: changelog/langai-changelog.yml
- type: ChangeLog
  url: https://roadmap.lang.ai/changelog
- type: Roadmap
  url: https://roadmap.lang.ai/
- type: Plans
  url: plans/langai-plans-pricing.yml
- type: RateLimits
  url: rate-limits/langai-rate-limits.yml
- type: Examples
  url: examples/langai-request-examples.yml
- type: Packages
  url: packages/langai-packages.yml
x-enrichment:
  date: '2026-08-14'
  status: enriched
  artifacts_added: 6
  pass: local-v1
  note: 'Contract discovery re-run across five hosts (lang.ai, docs.lang.ai, help.lang.ai, capacity.com, api.capacity.com).
    Newly found: the public Canny changelog + RSS feed at roadmap.lang.ai, the Snowflake Marketplace Native App, and the empty
    langai-python SDK repo. No agent card, no MCP server, no AsyncAPI, no OAuth, no sandbox, no SDK.'

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