Ledger Investing Development Models API

openapi: 3.1.0
info:
  title: Ledger Analytics Cashflow Models Development Models API
  version: 0.0.30
  summary: Remote Bayesian actuarial compute over insurance loss triangles.
  description: 'The Ledger Analytics API provides remote compute access to Bayesian actuarial models

    for insurance loss triangles. It is operated by Korra Tech, LLC (d/b/a Korra), a wholly

    owned SaaS subsidiary of Ledger Investing, Inc., and is currently in beta.


    Loss triangles are uploaded and managed as first-class `triangle` resources. Development,

    tail, forecast and cashflow models are then fit against a named triangle. Fitting and

    prediction are executed as asynchronous remote tasks: the fit/predict call returns a task

    handle which is polled at `/tasks/{task_id}` until it completes; predictions are written

    back as new triangle resources.


    IMPORTANT PROVENANCE NOTE: Ledger/Korra do not publish an OpenAPI description. This

    document was DERIVED by API Evangelist from the request construction in the first-party,

    open-source `ledger-analytics` Python client (github.com/LedgerInvesting/ledger-analytics,

    MIT-licensed, Copyright 2025 Korra, LLC) and from the published documentation. Paths,

    methods, auth, request-body field names, pagination parameters and error semantics are

    taken verbatim from that client. Response schemas are partial — only the fields the

    client actually reads are described. It is not an authoritative provider artifact.

    '
  contact:
    name: Ledger Analytics
    email: analytics@ledgerinvesting.com
    url: https://ledger-investing-ledger-analytics.readthedocs-hosted.com/en/stable/index.html
  license:
    name: MIT
    url: https://github.com/LedgerInvesting/ledger-analytics/blob/main/LICENSE.txt
servers:
- url: https://api.korra.com/analytics
  description: Production
security:
- ApiKeyAuth: []
tags:
- name: Development Models
  description: Bayesian loss development models (ChainLadder, TraditionalChainLadder, ManualATA, MeyersCRC, GMCL).
paths:
  /development-model:
    get:
      tags:
      - Development Models
      operationId: listDevelopmentModels
      summary: List development models
      parameters:
      - $ref: '#/components/parameters/Limit'
      responses:
        '200':
          description: Paginated list of development models.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/PaginatedModelList'
        '403':
          $ref: '#/components/responses/Forbidden'
    post:
      tags:
      - Development Models
      operationId: fitDevelopmentModel
      summary: Fit a development model
      description: Fits a Bayesian loss development model against a named triangle. Returns a task handle to poll.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/ModelFitRequest'
      responses:
        '201':
          description: Fit task accepted.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ModelTaskResponse'
        '400':
          $ref: '#/components/responses/BadRequest'
        '403':
          $ref: '#/components/responses/Forbidden'
  /development-model-type:
    get:
      tags:
      - Development Models
      operationId: listDevelopmentModelTypes
      summary: List available development model types
      responses:
        '200':
          description: Available model types.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ModelTypeList'
  /development-model/{id}:
    parameters:
    - $ref: '#/components/parameters/ResourceId'
    get:
      tags:
      - Development Models
      operationId: getDevelopmentModel
      summary: Retrieve a development model
      responses:
        '200':
          description: The model.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Model'
        '404':
          $ref: '#/components/responses/NotFound'
    delete:
      tags:
      - Development Models
      operationId: deleteDevelopmentModel
      summary: Delete a development model
      responses:
        '204':
          description: Model deleted.
        '404':
          $ref: '#/components/responses/NotFound'
  /development-model/{id}/predict:
    parameters:
    - $ref: '#/components/parameters/ResourceId'
    post:
      tags:
      - Development Models
      operationId: predictDevelopmentModel
      summary: Predict from a development model
      description: Runs prediction for a fitted development model against a triangle; results are written back as a new triangle.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/ModelPredictRequest'
      responses:
        '201':
          description: Predict task accepted.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/PredictTaskResponse'
        '400':
          $ref: '#/components/responses/BadRequest'
  /development-model/{id}/terminate:
    parameters:
    - $ref: '#/components/parameters/ResourceId'
    post:
      tags:
      - Development Models
      operationId: terminateDevelopmentModel
      summary: Terminate a running development model task
      responses:
        '200':
          description: Termination requested.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Task'
components:
  schemas:
    PredictTaskResponse:
      type: object
      description: Response returned when a prediction is accepted.
      properties:
        predictions:
          type: string
          description: Identifier of the triangle the predictions will be written to.
        modal_task:
          type: object
          properties:
            id:
              type: string
              description: Task identifier to poll at `/tasks/{task_id}`.
    ModelTypeList:
      type: object
      description: Available model types for a model class.
      additionalProperties: true
    Pagination:
      type: object
      properties:
        count:
          type: integer
          description: Total number of matching objects.
        next:
          type:
          - string
          - 'null'
          description: URL of the next page, when present.
        previous:
          type:
          - string
          - 'null'
          description: URL of the previous page, when present.
    ModelFitRequest:
      type: object
      required:
      - triangle_name
      - model_name
      - model_type
      properties:
        triangle_name:
          type: string
          description: Name of the triangle to fit against.
        model_name:
          type: string
          description: Name to store the fitted model under.
        model_type:
          type: string
          description: Model type to fit.
          examples:
          - ChainLadder
          - TraditionalChainLadder
          - ManualATA
          - MeyersCRC
          - GMCL
          - GeneralizedBondy
          - Sherman
          - ClassicalPowerTransformTail
          - AR1
          - SSM
          - TraditionalGCC
        overwrite:
          type: boolean
          default: false
          description: Replace an existing model of the same name.
        model_config:
          type: object
          description: 'Model-specific configuration. Common members include `loss_family`, `seed`,

            `use_multivariate`, `informed_priors_version`, `priors`, and `autofit_override`

            (MCMC autofit controls). See the per-model reference in the documentation.

            '
          additionalProperties: true
    ModelTaskResponse:
      type: object
      description: Response returned when a fit is accepted.
      properties:
        model:
          type: object
          properties:
            id:
              type: string
        modal_task:
          type: object
          properties:
            id:
              type: string
              description: Task identifier to poll at `/tasks/{task_id}`.
    Task:
      type: object
      description: Asynchronous remote task state.
      properties:
        id:
          type: string
        status:
          type: string
          description: Task status, e.g. `created`, `pending`, `terminated`.
        task_response:
          type:
          - object
          - 'null'
          description: Null while the task is pending; populated on completion.
          additionalProperties: true
          properties:
            status:
              type: string
              description: '`success` when the task completed successfully.'
            error:
              type:
              - string
              - 'null'
              description: Failure detail when the task did not succeed.
    Error:
      type: object
      description: 'Error envelope. The client surfaces the decoded JSON body verbatim in the raised

        HTTPError message; the exact field names are not documented by the provider.

        '
      additionalProperties: true
    PaginatedModelList:
      allOf:
      - $ref: '#/components/schemas/Pagination'
      - type: object
        properties:
          results:
            type: array
            items:
              $ref: '#/components/schemas/Model'
    Model:
      type: object
      description: A fitted model resource.
      properties:
        id:
          type: string
        name:
          type: string
        triangle:
          type: object
          description: The triangle the model was fit against.
          properties:
            name:
              type: string
        modal_task_info:
          type: object
          description: Remote task metadata, including the arguments the model was fit with.
          properties:
            task_args:
              type: object
              properties:
                model_type:
                  type: string
                model_config:
                  type: object
                  additionalProperties: true
    ModelPredictRequest:
      type: object
      required:
      - triangle_name
      properties:
        triangle_name:
          type: string
          description: Name of the triangle to predict on.
        prediction_name:
          type: string
          description: Optional name to store the resulting prediction triangle under.
        overwrite:
          type: boolean
          default: false
        predict_config:
          type: object
          description: Prediction configuration; may include `target_triangle` naming a triangle to predict onto.
          additionalProperties: true
          properties:
            target_triangle:
              type: string
              description: Name of the triangle to project predictions onto.
  parameters:
    ResourceId:
      name: id
      in: path
      required: true
      description: Identifier of the resource.
      schema:
        type: string
    Limit:
      name: limit
      in: query
      required: false
      description: Maximum number of results to return per page.
      schema:
        type: integer
        default: 25
        minimum: 1
  responses:
    Forbidden:
      description: Forbidden — the API key does not have permission to perform this action.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    NotFound:
      description: Not found — the endpoint or resource does not exist.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
    BadRequest:
      description: Bad request — the payload was rejected.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
  securitySchemes:
    ApiKeyAuth:
      type: apiKey
      in: header
      name: Authorization
      description: 'API key credential sent as `Authorization: Api-Key <API_KEY>`. Keys are requested by

        emailing analytics@ledgerinvesting.com during the beta and managed at https://ldgr.app/api-keys.

        The Python client reads the key from the `LEDGER_ANALYTICS_API_KEY` environment variable.

        '
externalDocs:
  description: LedgerAnalytics Python documentation
  url: https://ledger-investing-ledger-analytics.readthedocs-hosted.com/en/stable/index.html