> ## Documentation Index
> Fetch the complete documentation index at: https://docs.trycactus.com/llms.txt
> Use this file to discover all available pages before exploring further.

# One section of a finished report

> One part of `results`, exactly as stored. Every figure is
`{state, value, reason}`: `known` and `zero` are established values,
`unavailable` means it could not be established (see `reason`),
`not_applicable` means it doesn't apply to the deal.




## OpenAPI

````yaml /api-reference/openapi.yaml get /v1/underwritings/{underwriting_id}/sections/{section}
openapi: 3.1.0
info:
  title: Cactus Partner API
  version: 1.0.0-draft.1
  summary: Document extraction and automated underwriting for CRE.
  description: |
    # Overview

    The Cactus Partner API provides two products:

    - **Extraction** — upload commercial real estate documents (offering
      memoranda, rent rolls, T-12 / operating statements, and other business
      documents) and receive structured, validated JSON with per-field
      confidence.
    - **Underwriting** — provide a property address, asset class, and
      notification email (documents optional) to run a full automated
      underwriting; results are delivered as a hosted financial-analysis
      report link plus a machine-readable summary.

    ## Authentication

    Every request carries an API key:
    `Authorization: Bearer ck_live_...` (or `ck_sandbox_...`).
    Keys are issued by Cactus at kickoff and can be rotated or revoked at
    any time.

    ## Products and access

    Accounts are enabled per product, so not every endpoint below is
    available to every account:

    | Product | Endpoints |
    | --- | --- |
    | Extraction | `/v1/extractions` |
    | Underwriting | `/v1/underwritings` |
    | Usage reporting | `/v1/usage` |

    `/v1/documents` and `/v1/webhook-endpoints` are available to every
    account — uploads and webhook delivery underpin both products.

    Calling an endpoint your account is not enabled for returns `403`
    with code `product_not_enabled`; contact api@trycactus.com to add a
    product. A `403` with code `missing_scope` means the account *is*
    enabled but this particular key was issued without that scope — use a
    key that carries it. The MCP server advertises only the tools your key
    can use, so the same rules apply there.

    ## Sandbox

    `ck_sandbox_` keys hit the same endpoints but never debit your usage
    pool: uploads are accepted, and jobs return deterministic fixture output
    within seconds. Use sandbox keys for integration development and CI.

    Registering a sandbox document under a documented example filename
    (e.g. `example-rent-roll-1.xlsx`) returns the real extracted output of
    that reference document — see the Sandbox guide for the full list.

    ## Asynchronous jobs

    Extractions and underwritings are asynchronous. Create the job (`202
    Accepted`), then either poll the job resource or register a webhook
    endpoint to receive signed events (recommended). Typical extraction
    turnaround is minutes.

    ## Billing semantics

    A document is **accepted** when it passes validation (size caps, page/row
    counts, type resolution). Acceptance debits your usage pool at the fixed
    rate-card price for the document type — before processing, so pricing is
    deterministic. Rejected documents are never charged. Documents exceeding
    their type's size cap bill as multiple units of the same type; the accept
    response discloses `billed.units`. Files over 500 pages or 100 MB are
    rejected outright.

    ## Idempotency

    All `POST` endpoints accept an `Idempotency-Key` header (any unique
    string, e.g. a UUID). Retrying a request with the same key returns the
    original response instead of creating a duplicate.

    ## Errors

    Errors follow RFC 9457 (`application/problem+json`) and always include a
    stable machine-readable `code` and the `request_id` to quote in support
    requests.

    ## Versioning

    The path major version (`/v1`) changes only for breaking API changes.
    Extraction output schemas are versioned independently per document type
    (e.g. `rent_roll.v1`) and declared in every result; breaking output
    changes ship as a new schema version with advance notice and an overlap
    window.

    ---
    All field-level output schemas — `RentRollData` (`rent_roll.v1`),
    `T12Data` (`t12.v1`), `OfferingMemorandumData`
    (`offering_memorandum.v1`), and `GenericDocumentData` (`facts.v1`) —
    are finalized against the extraction engine's real output.
  contact:
    name: Cactus API Support
    email: api@trycactus.com
  license:
    name: Proprietary — Cactus API License Agreement
    identifier: LicenseRef-Cactus-Partner-Agreement
servers:
  - url: https://api.trycactus.com
    description: Production (live and sandbox keys)
security:
  - apiKey: []
tags:
  - name: Documents
    description: Upload and manage documents via presigned URLs.
  - name: Extractions
    description: Structured data extraction jobs and results.
  - name: Underwritings
    description: Automated underwriting runs.
  - name: Usage
    description: Usage pool balance and metered activity.
  - name: Webhook Endpoints
    description: Manage endpoints that receive signed event notifications.
paths:
  /v1/underwritings/{underwriting_id}/sections/{section}:
    parameters:
      - $ref: '#/components/parameters/UnderwritingId'
      - $ref: '#/components/parameters/EndUser'
      - name: section
        in: path
        required: true
        schema:
          type: string
          enum:
            - answer
            - income
            - revenue
            - cost
            - value
            - buyer
            - risk
            - next
            - critical_assumptions
            - readiness
            - property
    get:
      tags:
        - Underwritings
      summary: One section of a finished report
      description: |
        One part of `results`, exactly as stored. Every figure is
        `{state, value, reason}`: `known` and `zero` are established values,
        `unavailable` means it could not be established (see `reason`),
        `not_applicable` means it doesn't apply to the deal.
      operationId: getUnderwritingSection
      responses:
        '200':
          description: The section.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/UnderwritingSection'
        '403':
          $ref: '#/components/responses/Forbidden'
        '404':
          $ref: '#/components/responses/NotFound'
        '409':
          description: The underwriting has not completed.
          content:
            application/problem+json:
              schema:
                $ref: '#/components/schemas/Problem'
        '422':
          description: Unknown section.
          content:
            application/problem+json:
              schema:
                $ref: '#/components/schemas/Problem'
components:
  parameters:
    UnderwritingId:
      name: underwriting_id
      in: path
      required: true
      schema:
        type: string
      example: uw_01J9ZK3M
    EndUser:
      name: X-Cactus-End-User
      in: header
      required: false
      schema:
        type: string
        maxLength: 255
      description: |
        Act for one of your end users (the `end_user_ref` you pass when
        creating underwritings). Limits every underwriting, document and
        extraction call to that user's resources. Required on MCP
        connections once your account serves end users.
  schemas:
    UnderwritingSection:
      type: object
      required:
        - object
        - underwriting_id
        - section
        - description
        - content
      properties:
        object:
          type: string
          const: underwriting_section
        underwriting_id:
          type: string
        section:
          type: string
        description:
          type: string
        content:
          description: The section exactly as in `results`.
    Problem:
      type: object
      description: RFC 9457 problem details.
      required:
        - title
        - status
        - code
        - request_id
      properties:
        type:
          type: string
          format: uri
          description: >
            Link to this code's entry on the errors page. An anchor, not a path
            — every code lives on the one page.
          example: https://docs.trycactus.com/errors#document_over_size_cap
        title:
          type: string
          example: Document exceeds the size limit
        status:
          type: integer
          example: 422
        detail:
          type: string
          example: Files over 500 pages or 100 MB are rejected and not charged.
        code:
          type: string
          description: Stable machine-readable error code.
          example: document_over_size_cap
        request_id:
          type: string
        errors:
          type: array
          description: Field-level validation errors, when applicable.
          items:
            type: object
            properties:
              field:
                type: string
              code:
                type: string
              message:
                type: string
  responses:
    Forbidden:
      description: >
        The key authenticated, but this product is not available to it.
        `product_not_enabled` — your account has not been enabled for this
        product; contact api@trycactus.com. `missing_scope` — your account has
        the product but this particular key was issued without it; use a key
        that carries the scope.
      content:
        application/problem+json:
          schema:
            $ref: '#/components/schemas/Problem'
          examples:
            product_not_enabled:
              summary: Account not enabled for the product
              value:
                type: https://docs.trycactus.com/errors#product_not_enabled
                title: Product not enabled for this account
                status: 403
                detail: >-
                  Your account is not enabled for underwriting. Contact
                  api@trycactus.com to enable it.
                code: product_not_enabled
                request_id: req_01J9Z6X2QK8N4M
            missing_scope:
              summary: Key narrower than the account
              value:
                type: https://docs.trycactus.com/errors#missing_scope
                title: API key lacks the required scope
                status: 403
                detail: >-
                  This API key does not have the 'underwriting' scope. Use a key
                  with underwriting access.
                code: missing_scope
                request_id: req_01J9Z6X2QK8N4M
    NotFound:
      description: Resource does not exist (or belongs to another partner).
      content:
        application/problem+json:
          schema:
            $ref: '#/components/schemas/Problem'
  securitySchemes:
    apiKey:
      type: http
      scheme: bearer
      bearerFormat: ck_live_* or ck_sandbox_*
      description: Partner API key issued by Cactus.

````

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