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

# CSS Fluid Typography Generator

> Generate a CSS clamp() type scale (XS to 4XL) that interpolates font size smoothly between a min and max viewport width, with a live resizable preview and the underlying slope/interpolation math shown. Runs entirely in your browser.

[Try CSS Fluid Typography Generator in your browser →](https://iotools.cloud/tool/css-fluid-typography-generator/)



## OpenAPI

````yaml https://api.iotools.cloud/v1/openapi post /v1/tool/css-fluid-typography-generator
openapi: 3.1.0
info:
  title: iotools.cloud API
  version: 1.0.0
  description: >-
    Run any iotools.cloud tool over HTTP.


    Authenticate with `Authorization: Bearer iot_live_…`.


    **Only `POST /v1/tool/{slug}` costs credits.** Every GET here — the catalog,
    a tool's schema, your balance — is free. A tool call is charged its own
    weight or your plan's per-call minimum, whichever is larger;
    `x-iotools-credit-cost` on each operation is quoted at the free-tier
    minimum, and `GET /v1/tools/list` returns the exact figure for your key.
    `GET /v1/me/credits` reports what you have left, and `GET /v1/me/usage`
    reports what it went on.


    Failures are RFC 9457 problem documents — branch on `code`.
servers:
  - url: https://api.iotools.cloud
    description: Production
security:
  - bearerAuth: []
tags:
  - name: Catalog
    description: Find a tool and read its contract. Free.
  - name: Converters
    description: >-
      Convert between formats, encodings, and units — Base64, CSV and JSON,
      timestamps, and more. Fast, free, and processed right in your browser.
  - name: Formatters
    description: >-
      Format, beautify, minify, and validate code and data — JSON, HTML, CSS,
      SQL, and regex. Clean up messy input in one click, with nothing to upload.
  - name: Generators
    description: >-
      Generate exactly what you need and on demand — passwords, UUIDs, QR codes,
      hashes, random numbers, and more. Secure, instant, and free.
  - name: Calculators
    description: >-
      Crunch the numbers fast — from everyday math to specialized conversions
      and unit work. Free online calculators that run entirely in your browser.
  - name: Editors
    description: >-
      Edit and transform text, code, and images with quick, focused editors that
      run entirely in your browser — nothing to install, and no sign-up needed.
  - name: Utilities
    description: >-
      Everyday developer and web utilities — DNS and IP lookups, redirect and
      certificate checkers, and other quick diagnostics. Free and
      privacy-friendly.
  - name: Account
    description: Your key's allowance, limits and usage history.
paths:
  /v1/tool/css-fluid-typography-generator:
    post:
      tags:
        - Generators
      summary: CSS Fluid Typography Generator
      description: >-
        Generate a CSS clamp() type scale (XS to 4XL) that interpolates font
        size smoothly between a min and max viewport width, with a live
        resizable preview and the underlying slope/interpolation math shown.
        Runs entirely in your browser.


        [Try CSS Fluid Typography Generator in your browser
        →](https://iotools.cloud/tool/css-fluid-typography-generator/)
      operationId: run_css_fluid_typography_generator
      requestBody:
        required: false
        content:
          application/json:
            schema:
              type: object
              properties:
                minFontSize:
                  type: number
                  description: Min font size (px)
                  minimum: 8
                  maximum: 40
                maxFontSize:
                  type: number
                  description: Max font size (px)
                  minimum: 8
                  maximum: 72
                minViewport:
                  type: number
                  description: Min viewport width (px)
                  minimum: 280
                  maximum: 768
                maxViewport:
                  type: number
                  description: Max viewport width (px)
                  minimum: 768
                  maximum: 2560
                minRatio:
                  enum:
                    - '1.067'
                    - '1.125'
                    - '1.2'
                    - '1.25'
                    - '1.333'
                    - '1.414'
                    - '1.5'
                    - '1.618'
                  description: Scale ratio at min viewport
                maxRatio:
                  enum:
                    - '1.067'
                    - '1.125'
                    - '1.2'
                    - '1.25'
                    - '1.333'
                    - '1.414'
                    - '1.5'
                    - '1.618'
                  description: Scale ratio at max viewport
                outputUnit:
                  enum:
                    - rem
                    - px
                  description: Output unit
                asCustomProperties:
                  type: boolean
                  description: Output as CSS custom properties
              required: []
            examples:
              default_rem_custom_properties:
                summary: Default (rem, custom properties)
                value:
                  minFontSize: '16'
                  maxFontSize: '20'
                  minViewport: '320'
                  maxViewport: '1200'
                  minRatio: '1.2'
                  maxRatio: '1.25'
                  outputUnit: rem
                  asCustomProperties: 'true'
              utility_classes_px:
                summary: Utility classes (px)
                value:
                  minFontSize: '14'
                  maxFontSize: '18'
                  minViewport: '375'
                  maxViewport: '1440'
                  minRatio: '1.125'
                  maxRatio: '1.333'
                  outputUnit: px
                  asCustomProperties: ''
      responses:
        '200':
          description: Tool output
          content:
            application/json:
              examples:
                default_rem_custom_properties:
                  summary: Default (rem, custom properties)
                  value:
                    tool: css-fluid-typography-generator
                    tool_version: 1.0.1
                    outputs:
                      cssCode: |-
                        :root {
                          --font-xs: clamp(0.6944rem, 0.6561rem + 0.1919vw, 0.8rem);
                          --font-sm: clamp(0.8333rem, 0.7727rem + 0.303vw, 1rem);
                          --font-base: clamp(1rem, 0.9091rem + 0.4545vw, 1.25rem);
                          --font-lg: clamp(1.2rem, 1.0682rem + 0.6591vw, 1.5625rem);
                          --font-xl: clamp(1.44rem, 1.2534rem + 0.933vw, 1.9531rem);
                          --font-2xl: clamp(1.728rem, 1.4686rem + 1.2971vw, 2.4414rem);
                          --font-3xl: clamp(2.0736rem, 1.7179rem + 1.7785vw, 3.0518rem);
                          --font-4xl: clamp(2.4883rem, 2.006rem + 2.4116vw, 3.8147rem);
                        }

                        /* Usage */
                        h1 { font-size: var(--font-3xl); }
                        p  { font-size: var(--font-base); }
                      scaleTable:
                        - step: XS
                          min: 0.6944rem
                          max: 0.8rem
                          clamp: clamp(0.6944rem, 0.6561rem + 0.1919vw, 0.8rem)
                        - step: SM
                          min: 0.8333rem
                          max: 1rem
                          clamp: clamp(0.8333rem, 0.7727rem + 0.303vw, 1rem)
                        - step: Base
                          min: 1rem
                          max: 1.25rem
                          clamp: clamp(1rem, 0.9091rem + 0.4545vw, 1.25rem)
                        - step: LG
                          min: 1.2rem
                          max: 1.5625rem
                          clamp: clamp(1.2rem, 1.0682rem + 0.6591vw, 1.5625rem)
                        - step: XL
                          min: 1.44rem
                          max: 1.9531rem
                          clamp: clamp(1.44rem, 1.2534rem + 0.933vw, 1.9531rem)
                        - step: 2XL
                          min: 1.728rem
                          max: 2.4414rem
                          clamp: clamp(1.728rem, 1.4686rem + 1.2971vw, 2.4414rem)
                        - step: 3XL
                          min: 2.0736rem
                          max: 3.0518rem
                          clamp: clamp(2.0736rem, 1.7179rem + 1.7785vw, 3.0518rem)
                        - step: 4XL
                          min: 2.4883rem
                          max: 3.8147rem
                          clamp: clamp(2.4883rem, 2.006rem + 2.4116vw, 3.8147rem)
                      previewHtml: >-
                        <div class="io-ftg-demo"><p class="io-ftg-xs">The quick
                        brown fox — XS</p><p class="io-ftg-sm">The quick brown
                        fox — SM</p><p class="io-ftg-base">The quick brown fox —
                        Base</p><p class="io-ftg-lg">The quick brown fox —
                        LG</p><p class="io-ftg-xl">The quick brown fox —
                        XL</p><p class="io-ftg-2xl">The quick brown fox —
                        2XL</p><p class="io-ftg-3xl">The quick brown fox —
                        3XL</p><p class="io-ftg-4xl">The quick brown fox —
                        4XL</p></div>
                      previewCss: >-
                        .io-ftg-demo { font-family: system-ui, sans-serif;
                        color: #1a1a2e; }

                        .io-ftg-demo p { margin: 0 0 0.5em 0; line-height: 1.3;
                        }

                        .io-ftg-xs { font-size: clamp(0.6944rem, 0.6561rem +
                        0.1919vw, 0.8rem); }

                        .io-ftg-sm { font-size: clamp(0.8333rem, 0.7727rem +
                        0.303vw, 1rem); }

                        .io-ftg-base { font-size: clamp(1rem, 0.9091rem +
                        0.4545vw, 1.25rem); }

                        .io-ftg-lg { font-size: clamp(1.2rem, 1.0682rem +
                        0.6591vw, 1.5625rem); }

                        .io-ftg-xl { font-size: clamp(1.44rem, 1.2534rem +
                        0.933vw, 1.9531rem); }

                        .io-ftg-2xl { font-size: clamp(1.728rem, 1.4686rem +
                        1.2971vw, 2.4414rem); }

                        .io-ftg-3xl { font-size: clamp(2.0736rem, 1.7179rem +
                        1.7785vw, 3.0518rem); }

                        .io-ftg-4xl { font-size: clamp(2.4883rem, 2.006rem +
                        2.4116vw, 3.8147rem); }
                    credits_used: 3
                    credits_remaining: null
                utility_classes_px:
                  summary: Utility classes (px)
                  value:
                    tool: css-fluid-typography-generator
                    tool_version: 1.0.1
                    outputs:
                      cssCode: |-
                        .text-xs {
                          font-size: clamp(10.13px, 11.39px + -0.0875vw, 11.06px);
                        }

                        .text-sm {
                          font-size: clamp(12.44px, 12.07px + 0.0994vw, 13.5px);
                        }

                        .text-base {
                          font-size: clamp(14px, 12.59px + 0.3756vw, 18px);
                        }

                        .text-lg {
                          font-size: clamp(15.75px, 12.85px + 0.7741vw, 23.99px);
                        }

                        .text-xl {
                          font-size: clamp(17.72px, 12.7px + 1.3395vw, 31.98px);
                        }

                        .text-2xl {
                          font-size: clamp(19.93px, 11.94px + 2.1316vw, 42.63px);
                        }

                        .text-3xl {
                          font-size: clamp(22.43px, 10.31px + 3.2307vw, 56.83px);
                        }

                        .text-4xl {
                          font-size: clamp(25.23px, 7.44px + 4.7445vw, 75.76px);
                        }
                      scaleTable:
                        - step: XS
                          min: 11.06px
                          max: 10.13px
                          clamp: clamp(10.13px, 11.39px + -0.0875vw, 11.06px)
                        - step: SM
                          min: 12.44px
                          max: 13.5px
                          clamp: clamp(12.44px, 12.07px + 0.0994vw, 13.5px)
                        - step: Base
                          min: 14px
                          max: 18px
                          clamp: clamp(14px, 12.59px + 0.3756vw, 18px)
                        - step: LG
                          min: 15.75px
                          max: 23.99px
                          clamp: clamp(15.75px, 12.85px + 0.7741vw, 23.99px)
                        - step: XL
                          min: 17.72px
                          max: 31.98px
                          clamp: clamp(17.72px, 12.7px + 1.3395vw, 31.98px)
                        - step: 2XL
                          min: 19.93px
                          max: 42.63px
                          clamp: clamp(19.93px, 11.94px + 2.1316vw, 42.63px)
                        - step: 3XL
                          min: 22.43px
                          max: 56.83px
                          clamp: clamp(22.43px, 10.31px + 3.2307vw, 56.83px)
                        - step: 4XL
                          min: 25.23px
                          max: 75.76px
                          clamp: clamp(25.23px, 7.44px + 4.7445vw, 75.76px)
                      previewHtml: >-
                        <div class="io-ftg-demo"><p class="io-ftg-xs">The quick
                        brown fox — XS</p><p class="io-ftg-sm">The quick brown
                        fox — SM</p><p class="io-ftg-base">The quick brown fox —
                        Base</p><p class="io-ftg-lg">The quick brown fox —
                        LG</p><p class="io-ftg-xl">The quick brown fox —
                        XL</p><p class="io-ftg-2xl">The quick brown fox —
                        2XL</p><p class="io-ftg-3xl">The quick brown fox —
                        3XL</p><p class="io-ftg-4xl">The quick brown fox —
                        4XL</p></div>
                      previewCss: >-
                        .io-ftg-demo { font-family: system-ui, sans-serif;
                        color: #1a1a2e; }

                        .io-ftg-demo p { margin: 0 0 0.5em 0; line-height: 1.3;
                        }

                        .io-ftg-xs { font-size: clamp(10.13px, 11.39px +
                        -0.0875vw, 11.06px); }

                        .io-ftg-sm { font-size: clamp(12.44px, 12.07px +
                        0.0994vw, 13.5px); }

                        .io-ftg-base { font-size: clamp(14px, 12.59px +
                        0.3756vw, 18px); }

                        .io-ftg-lg { font-size: clamp(15.75px, 12.85px +
                        0.7741vw, 23.99px); }

                        .io-ftg-xl { font-size: clamp(17.72px, 12.7px +
                        1.3395vw, 31.98px); }

                        .io-ftg-2xl { font-size: clamp(19.93px, 11.94px +
                        2.1316vw, 42.63px); }

                        .io-ftg-3xl { font-size: clamp(22.43px, 10.31px +
                        3.2307vw, 56.83px); }

                        .io-ftg-4xl { font-size: clamp(25.23px, 7.44px +
                        4.7445vw, 75.76px); }
                    credits_used: 3
                    credits_remaining: null
              schema:
                type: object
                required:
                  - tool
                  - tool_version
                  - outputs
                  - credits_used
                  - credits_remaining
                properties:
                  outputs:
                    type: object
                    properties:
                      cssCode:
                        type: string
                        description: CSS output
                      scaleTable:
                        type: array
                        description: Type scale breakdown
                        items:
                          type: object
                          properties:
                            step:
                              type: string
                              description: Step
                            min:
                              type: string
                              description: Min
                            max:
                              type: string
                              description: Max
                            clamp:
                              type: string
                              description: clamp()
                        x-iotools-columns:
                          - step
                          - min
                          - max
                          - clamp
                      previewHtml:
                        type: string
                        description: Preview HTML
                      previewCss:
                        type: string
                        description: Preview CSS
                  tool:
                    type: string
                    description: The tool's slug, echoing the {slug} in the request path.
                  tool_version:
                    type: string
                    description: Output-contract version for this tool.
                  credits_used:
                    type: integer
                    description: >-
                      Credits this call consumed, after any settlement refund. 0
                      when metering is disabled.
                  credits_remaining:
                    type:
                      - integer
                      - 'null'
                    description: >-
                      Credits left in the current monthly allowance, or null
                      when metering is disabled.
                  request_id:
                    type: string
                    description: Correlation id, also sent as x-request-id.
        '400':
          $ref: '#/components/responses/ValidationError'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '402':
          $ref: '#/components/responses/InsufficientCredits'
        '403':
          $ref: '#/components/responses/ToolNotAllowed'
        '404':
          $ref: '#/components/responses/ToolNotFound'
        '413':
          $ref: '#/components/responses/PayloadTooLarge'
        '429':
          $ref: '#/components/responses/RateLimited'
        '500':
          $ref: '#/components/responses/ToolFailed'
        '503':
          $ref: '#/components/responses/ToolDisabled'
      security:
        - bearerAuth: []
components:
  responses:
    ValidationError:
      description: Invalid request.
      content:
        application/problem+json:
          schema:
            type: object
            description: >-
              RFC 9457 problem document, served as application/problem+json.
              Branch on `code`; `title` is human prose and may be reworded
              without notice. Some failures add extension members — `fields` on
              validation errors, `retry_after` on 429s,
              `credits_used`/`credits_remaining` on billing-adjacent failures —
              documented on the responses that carry them.
            required:
              - type
              - title
              - status
              - code
            properties:
              type:
                type: string
                format: uri
                description: Stable documentation URI for this failure.
                examples:
                  - https://iotools.cloud/docs/errors/validation_error
              title:
                type: string
                description: Short human-readable summary of the failure.
                examples:
                  - Invalid request
              status:
                type: integer
                description: HTTP status code, matching the response's own status.
              code:
                type: string
                description: >-
                  Stable machine-readable error code — branch on this, not
                  `title`.
                enum:
                  - validation_error
              detail:
                type: string
                description: Human explanation of this occurrence.
              request_id:
                type: string
                description: Correlation id, also sent as x-request-id.
              fields:
                type:
                  - object
                  - string
                additionalProperties:
                  type: string
                description: >-
                  What failed: a map of field name → message. Absent when the
                  body itself is malformed; a single string when the failure
                  isn't tied to one field.
          example:
            type: https://iotools.cloud/docs/errors/validation_error
            title: Invalid request
            status: 400
            code: validation_error
            detail: One or more inputs are invalid — see `fields`.
            request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11
            fields:
              inputString: Required
    Unauthorized:
      description: Missing or invalid API key.
      content:
        application/problem+json:
          schema:
            type: object
            description: >-
              RFC 9457 problem document, served as application/problem+json.
              Branch on `code`; `title` is human prose and may be reworded
              without notice. Some failures add extension members — `fields` on
              validation errors, `retry_after` on 429s,
              `credits_used`/`credits_remaining` on billing-adjacent failures —
              documented on the responses that carry them.
            required:
              - type
              - title
              - status
              - code
            properties:
              type:
                type: string
                format: uri
                description: Stable documentation URI for this failure.
                examples:
                  - https://iotools.cloud/docs/errors/invalid_api_key
              title:
                type: string
                description: Short human-readable summary of the failure.
                examples:
                  - Invalid API key
              status:
                type: integer
                description: HTTP status code, matching the response's own status.
              code:
                type: string
                description: >-
                  Stable machine-readable error code — branch on this, not
                  `title`.
                enum:
                  - invalid_api_key
              detail:
                type: string
                description: Human explanation of this occurrence.
              request_id:
                type: string
                description: Correlation id, also sent as x-request-id.
          example:
            type: https://iotools.cloud/docs/errors/invalid_api_key
            title: Invalid API key
            status: 401
            code: invalid_api_key
            detail: 'Provide ''Authorization: Bearer <key>''.'
            request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11
    InsufficientCredits:
      description: Monthly credit allowance exhausted.
      content:
        application/problem+json:
          schema:
            type: object
            description: >-
              RFC 9457 problem document, served as application/problem+json.
              Branch on `code`; `title` is human prose and may be reworded
              without notice. Some failures add extension members — `fields` on
              validation errors, `retry_after` on 429s,
              `credits_used`/`credits_remaining` on billing-adjacent failures —
              documented on the responses that carry them.
            required:
              - type
              - title
              - status
              - code
            properties:
              type:
                type: string
                format: uri
                description: Stable documentation URI for this failure.
                examples:
                  - https://iotools.cloud/docs/errors/insufficient_credits
              title:
                type: string
                description: Short human-readable summary of the failure.
                examples:
                  - Insufficient credits
              status:
                type: integer
                description: HTTP status code, matching the response's own status.
              code:
                type: string
                description: >-
                  Stable machine-readable error code — branch on this, not
                  `title`.
                enum:
                  - insufficient_credits
              detail:
                type: string
                description: Human explanation of this occurrence.
              request_id:
                type: string
                description: Correlation id, also sent as x-request-id.
              credits_used:
                type: integer
                description: Always 0 — a refused call charges nothing.
              credits_remaining:
                type: integer
                description: Credits left in the allowance — fewer than this call costs.
          example:
            type: https://iotools.cloud/docs/errors/insufficient_credits
            title: Insufficient credits
            status: 402
            code: insufficient_credits
            detail: This call costs 1 credit and 0 remain in this month's allowance.
            request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11
            credits_used: 0
            credits_remaining: 0
    ToolNotAllowed:
      description: Tool exists but has no API surface.
      content:
        application/problem+json:
          schema:
            type: object
            description: >-
              RFC 9457 problem document, served as application/problem+json.
              Branch on `code`; `title` is human prose and may be reworded
              without notice. Some failures add extension members — `fields` on
              validation errors, `retry_after` on 429s,
              `credits_used`/`credits_remaining` on billing-adjacent failures —
              documented on the responses that carry them.
            required:
              - type
              - title
              - status
              - code
            properties:
              type:
                type: string
                format: uri
                description: Stable documentation URI for this failure.
                examples:
                  - https://iotools.cloud/docs/errors/tool_not_allowed
              title:
                type: string
                description: Short human-readable summary of the failure.
                examples:
                  - Tool not available over the API
              status:
                type: integer
                description: HTTP status code, matching the response's own status.
              code:
                type: string
                description: >-
                  Stable machine-readable error code — branch on this, not
                  `title`.
                enum:
                  - tool_not_allowed
              detail:
                type: string
                description: Human explanation of this occurrence.
              request_id:
                type: string
                description: Correlation id, also sent as x-request-id.
          example:
            type: https://iotools.cloud/docs/errors/tool_not_allowed
            title: Tool not available over the API
            status: 403
            code: tool_not_allowed
            detail: >-
              "Background Remover" is available on iotools.cloud but has no API
              endpoint.
            request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11
    ToolNotFound:
      description: No such tool.
      content:
        application/problem+json:
          schema:
            type: object
            description: >-
              RFC 9457 problem document, served as application/problem+json.
              Branch on `code`; `title` is human prose and may be reworded
              without notice. Some failures add extension members — `fields` on
              validation errors, `retry_after` on 429s,
              `credits_used`/`credits_remaining` on billing-adjacent failures —
              documented on the responses that carry them.
            required:
              - type
              - title
              - status
              - code
            properties:
              type:
                type: string
                format: uri
                description: Stable documentation URI for this failure.
                examples:
                  - https://iotools.cloud/docs/errors/tool_not_found
              title:
                type: string
                description: Short human-readable summary of the failure.
                examples:
                  - Tool not found
              status:
                type: integer
                description: HTTP status code, matching the response's own status.
              code:
                type: string
                description: >-
                  Stable machine-readable error code — branch on this, not
                  `title`.
                enum:
                  - tool_not_found
              detail:
                type: string
                description: Human explanation of this occurrence.
              request_id:
                type: string
                description: Correlation id, also sent as x-request-id.
          example:
            type: https://iotools.cloud/docs/errors/tool_not_found
            title: Tool not found
            status: 404
            code: tool_not_found
            detail: No tool with that slug. See GET /v1/tools/list.
            request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11
    PayloadTooLarge:
      description: Body too large.
      content:
        application/problem+json:
          schema:
            type: object
            description: >-
              RFC 9457 problem document, served as application/problem+json.
              Branch on `code`; `title` is human prose and may be reworded
              without notice. Some failures add extension members — `fields` on
              validation errors, `retry_after` on 429s,
              `credits_used`/`credits_remaining` on billing-adjacent failures —
              documented on the responses that carry them.
            required:
              - type
              - title
              - status
              - code
            properties:
              type:
                type: string
                format: uri
                description: Stable documentation URI for this failure.
                examples:
                  - https://iotools.cloud/docs/errors/payload_too_large
              title:
                type: string
                description: Short human-readable summary of the failure.
                examples:
                  - Payload too large
              status:
                type: integer
                description: HTTP status code, matching the response's own status.
              code:
                type: string
                description: >-
                  Stable machine-readable error code — branch on this, not
                  `title`.
                enum:
                  - payload_too_large
              detail:
                type: string
                description: Human explanation of this occurrence.
              request_id:
                type: string
                description: Correlation id, also sent as x-request-id.
          example:
            type: https://iotools.cloud/docs/errors/payload_too_large
            title: Payload too large
            status: 413
            code: payload_too_large
            detail: Request body exceeds this tool's size limit.
            request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11
    RateLimited:
      description: Per-minute rate limit exceeded.
      headers:
        Retry-After:
          description: Seconds to wait before retrying (RFC 9110 delta-seconds).
          schema:
            type: integer
      content:
        application/problem+json:
          schema:
            type: object
            description: >-
              RFC 9457 problem document, served as application/problem+json.
              Branch on `code`; `title` is human prose and may be reworded
              without notice. Some failures add extension members — `fields` on
              validation errors, `retry_after` on 429s,
              `credits_used`/`credits_remaining` on billing-adjacent failures —
              documented on the responses that carry them.
            required:
              - type
              - title
              - status
              - code
            properties:
              type:
                type: string
                format: uri
                description: Stable documentation URI for this failure.
                examples:
                  - https://iotools.cloud/docs/errors/rate_limited
              title:
                type: string
                description: Short human-readable summary of the failure.
                examples:
                  - Rate limit exceeded
              status:
                type: integer
                description: HTTP status code, matching the response's own status.
              code:
                type: string
                description: >-
                  Stable machine-readable error code — branch on this, not
                  `title`.
                enum:
                  - rate_limited
              detail:
                type: string
                description: Human explanation of this occurrence.
              request_id:
                type: string
                description: Correlation id, also sent as x-request-id.
              retry_after:
                type: integer
                description: >-
                  Seconds until the window resets — the same value as the
                  `Retry-After` header.
          example:
            type: https://iotools.cloud/docs/errors/rate_limited
            title: Rate limit exceeded
            status: 429
            code: rate_limited
            detail: Too many requests. Retry in 30s.
            request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11
            retry_after: 30
    ToolFailed:
      description: Tool failed to run.
      content:
        application/problem+json:
          schema:
            type: object
            description: >-
              RFC 9457 problem document, served as application/problem+json.
              Branch on `code`; `title` is human prose and may be reworded
              without notice. Some failures add extension members — `fields` on
              validation errors, `retry_after` on 429s,
              `credits_used`/`credits_remaining` on billing-adjacent failures —
              documented on the responses that carry them.
            required:
              - type
              - title
              - status
              - code
            properties:
              type:
                type: string
                format: uri
                description: Stable documentation URI for this failure.
                examples:
                  - https://iotools.cloud/docs/errors/processing_error
                  - https://iotools.cloud/docs/errors/internal_error
              title:
                type: string
                description: Short human-readable summary of the failure.
                examples:
                  - Tool failed to run
                  - Internal error
              status:
                type: integer
                description: HTTP status code, matching the response's own status.
              code:
                type: string
                description: >-
                  Stable machine-readable error code — branch on this, not
                  `title`.
                enum:
                  - processing_error
                  - internal_error
              detail:
                type: string
                description: Human explanation of this occurrence.
              request_id:
                type: string
                description: Correlation id, also sent as x-request-id.
              credits_used:
                type: integer
                description: >-
                  Always 0 on `processing_error` — a failed run is refunded,
                  floor included.
              credits_remaining:
                type: integer
                description: >-
                  Credits left after the refund. Absent when metering is
                  disabled.
          example:
            type: https://iotools.cloud/docs/errors/processing_error
            title: Tool failed to run
            status: 500
            code: processing_error
            detail: The tool failed to run. Please try again.
            request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11
            credits_used: 0
    ToolDisabled:
      description: Tool temporarily disabled.
      content:
        application/problem+json:
          schema:
            type: object
            description: >-
              RFC 9457 problem document, served as application/problem+json.
              Branch on `code`; `title` is human prose and may be reworded
              without notice. Some failures add extension members — `fields` on
              validation errors, `retry_after` on 429s,
              `credits_used`/`credits_remaining` on billing-adjacent failures —
              documented on the responses that carry them.
            required:
              - type
              - title
              - status
              - code
            properties:
              type:
                type: string
                format: uri
                description: Stable documentation URI for this failure.
                examples:
                  - https://iotools.cloud/docs/errors/tool_disabled
                  - https://iotools.cloud/docs/errors/api_unconfigured
              title:
                type: string
                description: Short human-readable summary of the failure.
                examples:
                  - Tool temporarily disabled
                  - API not configured
              status:
                type: integer
                description: HTTP status code, matching the response's own status.
              code:
                type: string
                description: >-
                  Stable machine-readable error code — branch on this, not
                  `title`.
                enum:
                  - tool_disabled
                  - api_unconfigured
              detail:
                type: string
                description: Human explanation of this occurrence.
              request_id:
                type: string
                description: Correlation id, also sent as x-request-id.
          example:
            type: https://iotools.cloud/docs/errors/tool_disabled
            title: Tool temporarily disabled
            status: 503
            code: tool_disabled
            detail: This tool is temporarily unavailable. Try again shortly.
            request_id: e4042b29-8f1e-4c7a-9b52-6f0d1a3c7e11
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: iot_live_…

````