Lang.ai

Lang.ai Documents API

Analyze and save documents against a project.

GitHub OpenAPI

Operations 2

POST /analyze Analyze a document #
POST /documents Save a document #

Documentation

📖
Documentation
https://docs.lang.ai/
📖
APIReference
https://docs.lang.ai/
📖
Authentication
https://raw.githubusercontent.com/api-evangelist/langai/refs/heads/main/authentication/langai-authentication.yml

Specifications

⚙
OpenAPI
https://raw.githubusercontent.com/api-evangelist/langai/refs/heads/main/openapi/langai-documents-api-openapi.yml

Other Resources

🔗
ErrorCatalog
https://raw.githubusercontent.com/api-evangelist/langai/refs/heads/main/errors/langai-problem-types.yml
🔗
DataModel
https://raw.githubusercontent.com/api-evangelist/langai/refs/heads/main/data-model/langai-data-model.yml
🔗
APIsJSON
https://raw.githubusercontent.com/api-evangelist/langai/refs/heads/main/apis.yml

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OpenAPI Specification

langai-documents-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  title: Lang.ai Documents API
  version: '1.0'
  description: The Lang.ai API is organized around REST, with predictable resource-oriented URLs, HTTP verbs and HTTP response codes.
  contact:
    name: Lang.ai Help Center
    url: https://help.lang.ai/
  x-generated-by: api-evangelist-enrichment-pipeline
  x-generated-from: https://docs.lang.ai/
  x-method: generated
servers:
- url: https://{company}.lang.ai/api/v1
  description: Per-tenant Lang.ai instance. Replace the company variable with the subdomain of the Lang.ai instance you are using.
  variables:
    company:
      default: company
      description: The subdomain of your Lang.ai instance.
security:
- bearerAuth: []
tags:
- name: Documents
  description: Analyze and save documents against a project.
paths:
  /analyze:
    post:
      operationId: analyzeDocument
      tags:
      - Documents
      summary: Analyze a document
      description: Returns the classification for a given document and the specified project. The document is not persisted; use the save documents operation to store it.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/AnalyzeRequest'
            example:
              text: The text to be analyzed
              projectId: Your project id
      responses:
        '200':
          description: The tags and intents matched for the document.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Classification'
              example:
                tags:
                - id: tqGMbCpTBZOJaram
                  name: My first tag
                intents:
                - name: intent
                  features:
                  - feature
                  - feature>feature
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
        '429':
          $ref: '#/components/responses/TooManyRequests'
        '500':
          $ref: '#/components/responses/InternalServerError'
  /documents:
    post:
      operationId: saveDocument
      tags:
      - Documents
      summary: Save a document
      description: Saves a given document into the specified project and returns its classification. Supports passing metadata that can later be used in the project dashboard; new metadata values passed via the API become available in the project setup section. Supplying an id that already exists overwrites the stored document.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/SaveDocumentRequest'
            example:
              text: The text to be analyzed
              projectId: Your project id
              metadata:
                key: value
                another_key: value
              date: '2019-20-12'
              id: The ID of the document to save.
      responses:
        '200':
          description: The tags and intents matched for the saved document.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Classification'
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
        '429':
          $ref: '#/components/responses/TooManyRequests'
        '500':
          $ref: '#/components/responses/InternalServerError'
components:
  schemas:
    Error:
      type: object
      description: JSON is returned by all API responses, including errors. Lang.ai documents the HTTP status codes but does not publish a field-level error envelope schema.
      additionalProperties: true
    SaveDocumentRequest:
      type: object
      required:
      - text
      - projectId
      properties:
        text:
          type: string
          description: The text to be classified.
        projectId:
          type: string
          description: The project to be used to classify the text.
        metadata:
          type: object
          description: The metadata information of the document.
          additionalProperties: true
        date:
          type: string
          description: The date of the document. Supports valid ISO 8601 dates. If not passed, the request time is used.
        id:
          type: string
          description: ID of the document to save. If a document with the same ID already exists, it will be overwritten.
    Intent:
      type: object
      properties:
        name:
          type: string
          description: The name of the intent.
        features:
          type: array
          description: An array of features. The sign ">" indicates a second-level feature.
          items:
            type: string
    Classification:
      type: object
      properties:
        tags:
          type: array
          description: An array of tags.
          items:
            $ref: '#/components/schemas/TagRef'
        intents:
          type: array
          description: An array of intents.
          items:
            $ref: '#/components/schemas/Intent'
    TagRef:
      type: object
      properties:
        id:
          type: string
          description: The ID of the tag.
        name:
          type: string
          description: The name of the tag.
    AnalyzeRequest:
      type: object
      required:
      - text
      - projectId
      properties:
        text:
          type: string
          description: The text to be classified.
        projectId:
          type: string
          description: The project to be used to classify the text.
  responses:
    Unauthorized:
      description: Unauthorized
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    TooManyRequests:
      description: Too many requests / Rate limited
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    InternalServerError:
      description: Internal server error
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    NotFound:
      description: Project not found
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    BadRequest:
      description: Bad request / Missing fields
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: 'Authenticate your account by including your secret API token in every request as an Authorization: Bearer header. Create a new API token from the Settings section of your Lang.ai instance. Generating a new token invalidates previously issued ones.'