Cataas · API Governance Rules

Cataas API Rules

Spectral linting rules defining API design standards and conventions for Cataas.

40 Rules error 12 warn 24 info 4
Generated by API Evangelist Written by API Evangelist tooling for Cataas's APIs. It is a starting point, not a ruleset Cataas publishes or enforces.
View Rules File View on GitHub

Rule Categories

error http info microcks no openapi operation parameter path paths query request response schema security servers tag

Rules

warn
info-title-cataas-prefix
Info title must include the Cataas brand.
$.info.title
warn
info-description-required
Info description is required and must be substantive.
$.info
info
info-contact-defined
Info contact block should be defined.
$.info
info
info-license-defined
Info license block should be defined.
$.info
error
openapi-version-3
OpenAPI version must be 3.x.
$.openapi
error
servers-https-required
Server URLs must use HTTPS.
$.servers[*].url
warn
servers-description-required
Each server should have a description.
$.servers[*]
warn
paths-kebab-case
Path segments must use lowercase kebab-case (excluding {placeholders}).
$.paths.*~
error
paths-no-trailing-slash
Paths must not end with a trailing slash.
$.paths.*~
error
paths-no-query-string
Paths must not contain query strings.
$.paths.*~
error
operation-operationid-required
Every operation must have an operationId.
$.paths.*.*
warn
operation-operationid-camel-case
operationId must be lowerCamelCase.
$.paths.*.*.operationId
warn
operation-operationid-verb-prefix
operationId should begin with a recognised verb (get/list/create/update/delete/upload/admin).
$.paths.*.*.operationId
error
operation-summary-required
Every operation must have a summary.
$.paths.*.*
warn
operation-summary-cataas-prefix
Operation summaries should begin with 'CATAAS'.
$.paths.*.*.summary
warn
operation-description-required
Every operation must have a description.
$.paths.*.*
warn
operation-tags-required
Every operation must have at least one tag.
$.paths.*.*
warn
tag-global-list-defined
Global tags array must be defined.
$
warn
tag-description-required
Each global tag must have a description.
$.tags[*]
warn
tag-title-case
Tag names must be Title Case (no hyphens, no underscores).
$.tags[*].name
warn
parameter-description-required
Every parameter must have a description.
$.paths.*.*.parameters[*]
error
parameter-schema-required
Every parameter must define a schema.
$.paths.*.*.parameters[*]
error
request-body-content-required
Request bodies must declare content.
$.paths.*.*.requestBody
error
response-success-required
Every operation must define at least one 2xx response.
$.paths.*.*.responses
error
response-description-required
Every response must have a description.
$.paths.*.*.responses.*
info
schema-property-snake-case
Schema property names should be snake_case (with allowance for camelCase font* overlay params).
$.components.schemas.*.properties.*~
warn
schema-type-required
Schema property must declare a type (or $ref / oneOf / anyOf / allOf).
$.components.schemas.*.properties.*
warn
security-schemes-defined
Security schemes must be defined under components.
$.components
warn
security-admin-bearer
Admin operations should require bearer auth.
$.paths[?(@property.match(/^\/admin\//))].*
error
http-get-no-request-body
GET operations must not define a request body.
$.paths.*.get
error
http-delete-no-request-body
DELETE operations must not define a request body.
$.paths.*.delete
warn
http-post-has-request-body
POST operations should define a request body.
$.paths.*.post
info
microcks-extension-encouraged
Operations should define x-microcks-operation for mock compatibility.
$.paths.*.*
warn
servers-expected-domain
Server URLs should be on the cataas.com domain.
$.servers[*].url
warn
path-params-casing
Path parameters should be snake_case (the dominant convention in this API).
$.paths[*].parameters[?(@.in=='path')].name
warn
query-params-casing
Query parameters should be snake_case (the dominant convention in this API).
$.paths[*][get,post,put,patch,delete].parameters[?(@.in=='query')]
warn
schema-names-casing
Component schema names should be PascalCase (the dominant convention in this API).
$.components.schemas
warn
schema-properties-casing
Schema properties should be snake_case (the dominant convention in this API).
$.components.schemas[*].properties
warn
error-schema-defined
A shared error schema (ErrorResponse) should be defined for error payloads.
$.components.schemas
warn
no-empty-descriptions
Descriptions must not be empty strings.
$..description

Spectral Ruleset

Raw ↑
# authorship: generated by API Evangelist tooling. Stamped 2026-08-18
# on the file's own generator header (roadmap#64). An unmarked file is
# NOT assumed to be ours -- absence of evidence was never stamped.
x-method: generated
# cataas — Spectral ruleset (strengthened)
# Plain Spectral. Existing hand-authored rules preserved; measured rules added
# from this provider's own OpenAPI conventions by strengthen_ruleset.py,
# then self-validated against the spec.
#
# Provenance:
#   - servers-https-only: 100% of servers already https (error)
#   - servers-expected-domain: 1/1 servers on cataas.com
#   - path-params-casing: snake @ 100% (n=10)
#   - query-params-casing: snake @ 83% (n=52)
#   - operationid-casing: camel @ 100% (n=15)
#   - schema-names-casing: pascal @ 100% (n=5)
#   - schema-properties-casing: snake @ 93% (n=14)
#   - security: neither global nor consistently per-op — schemes-defined only
#   - error-schema-defined: ErrorResponse
#   - pagination params observed: ['limit']
#   - merge: kept 33 existing, added 7 measured, upgraded 0
#   - added: servers-expected-domain, path-params-casing, query-params-casing, schema-names-casing, schema-properties-casing, error-schema-defined, no-empty-descriptions
extends:
  - spectral:oas
rules:
  info-title-cataas-prefix:
    description: Info title must include the Cataas brand.
    severity: warn
    given: $.info.title
    then:
      function: pattern
      functionOptions:
        match: .*[Cc]ataas.*
  info-description-required:
    description: Info description is required and must be substantive.
    severity: warn
    given: $.info
    then:
      field: description
      function: truthy
  info-contact-defined:
    description: Info contact block should be defined.
    severity: info
    given: $.info
    then:
      field: contact
      function: truthy
  info-license-defined:
    description: Info license block should be defined.
    severity: info
    given: $.info
    then:
      field: license
      function: truthy
  openapi-version-3:
    description: OpenAPI version must be 3.x.
    severity: error
    given: $.openapi
    then:
      function: pattern
      functionOptions:
        match: ^3\.
  servers-https-required:
    description: Server URLs must use HTTPS.
    severity: error
    given: $.servers[*].url
    then:
      function: pattern
      functionOptions:
        match: ^https://
  servers-description-required:
    description: Each server should have a description.
    severity: warn
    given: $.servers[*]
    then:
      field: description
      function: truthy
  paths-kebab-case:
    description: Path segments must use lowercase kebab-case (excluding {placeholders}).
    severity: warn
    given: $.paths.*~
    then:
      function: pattern
      functionOptions:
        match: ^(/([a-z0-9]+(-[a-z0-9]+)*|\{[a-zA-Z]+\}))+$
  paths-no-trailing-slash:
    description: Paths must not end with a trailing slash.
    severity: error
    given: $.paths.*~
    then:
      function: pattern
      functionOptions:
        notMatch: /$
  paths-no-query-string:
    description: Paths must not contain query strings.
    severity: error
    given: $.paths.*~
    then:
      function: pattern
      functionOptions:
        notMatch: \?
  operation-operationid-required:
    description: Every operation must have an operationId.
    severity: error
    given: $.paths.*.*
    then:
      field: operationId
      function: truthy
  operation-operationid-camel-case:
    description: operationId must be lowerCamelCase.
    severity: warn
    given: $.paths.*.*.operationId
    then:
      function: pattern
      functionOptions:
        match: ^[a-z][a-zA-Z0-9]*$
  operation-operationid-verb-prefix:
    description: operationId should begin with a recognised verb (get/list/create/update/delete/upload/admin).
    severity: warn
    given: $.paths.*.*.operationId
    then:
      function: pattern
      functionOptions:
        match: ^(get|list|create|update|patch|delete|upload|admin)
  operation-summary-required:
    description: Every operation must have a summary.
    severity: error
    given: $.paths.*.*
    then:
      field: summary
      function: truthy
  operation-summary-cataas-prefix:
    description: Operation summaries should begin with 'CATAAS'.
    severity: warn
    given: $.paths.*.*.summary
    then:
      function: pattern
      functionOptions:
        match: '^CATAAS '
  operation-description-required:
    description: Every operation must have a description.
    severity: warn
    given: $.paths.*.*
    then:
      field: description
      function: truthy
  operation-tags-required:
    description: Every operation must have at least one tag.
    severity: warn
    given: $.paths.*.*
    then:
      field: tags
      function: truthy
  tag-global-list-defined:
    description: Global tags array must be defined.
    severity: warn
    given: $
    then:
      field: tags
      function: truthy
  tag-description-required:
    description: Each global tag must have a description.
    severity: warn
    given: $.tags[*]
    then:
      field: description
      function: truthy
  tag-title-case:
    description: Tag names must be Title Case (no hyphens, no underscores).
    severity: warn
    given: $.tags[*].name
    then:
      function: pattern
      functionOptions:
        match: ^[A-Z][A-Za-z0-9]*( [A-Z][A-Za-z0-9]*)*$
  parameter-description-required:
    description: Every parameter must have a description.
    severity: warn
    given: $.paths.*.*.parameters[*]
    then:
      field: description
      function: truthy
  parameter-schema-required:
    description: Every parameter must define a schema.
    severity: error
    given: $.paths.*.*.parameters[*]
    then:
      field: schema
      function: truthy
  request-body-content-required:
    description: Request bodies must declare content.
    severity: error
    given: $.paths.*.*.requestBody
    then:
      field: content
      function: truthy
  response-success-required:
    description: Every operation must define at least one 2xx response.
    severity: error
    given: $.paths.*.*.responses
    then:
      function: schema
      functionOptions:
        schema:
          type: object
          patternProperties:
            ^(2[0-9][0-9]|204)$:
              type: object
          additionalProperties: true
  response-description-required:
    description: Every response must have a description.
    severity: error
    given: $.paths.*.*.responses.*
    then:
      field: description
      function: truthy
  schema-property-snake-case:
    description: Schema property names should be snake_case (with allowance for camelCase font* overlay
      params).
    severity: info
    given: $.components.schemas.*.properties.*~
    then:
      function: pattern
      functionOptions:
        match: ^(_?[a-z][a-z0-9_]*|font[A-Z][a-zA-Z]+)$
  schema-type-required:
    description: Schema property must declare a type (or $ref / oneOf / anyOf / allOf).
    severity: warn
    given: $.components.schemas.*.properties.*
    then:
      function: schema
      functionOptions:
        schema:
          oneOf:
          - required:
            - type
          - required:
            - $ref
          - required:
            - oneOf
          - required:
            - anyOf
          - required:
            - allOf
  security-schemes-defined:
    description: Security schemes must be defined under components.
    severity: warn
    given: $.components
    then:
      field: securitySchemes
      function: truthy
  security-admin-bearer:
    description: Admin operations should require bearer auth.
    severity: warn
    given: $.paths[?(@property.match(/^\/admin\//))].*
    then:
      field: security
      function: truthy
  http-get-no-request-body:
    description: GET operations must not define a request body.
    severity: error
    given: $.paths.*.get
    then:
      field: requestBody
      function: falsy
  http-delete-no-request-body:
    description: DELETE operations must not define a request body.
    severity: error
    given: $.paths.*.delete
    then:
      field: requestBody
      function: falsy
  http-post-has-request-body:
    description: POST operations should define a request body.
    severity: warn
    given: $.paths.*.post
    then:
      field: requestBody
      function: truthy
  microcks-extension-encouraged:
    description: Operations should define x-microcks-operation for mock compatibility.
    severity: info
    given: $.paths.*.*
    then:
      field: x-microcks-operation
      function: truthy
  servers-expected-domain:
    description: Server URLs should be on the cataas.com domain.
    severity: warn
    given: $.servers[*].url
    then:
      function: pattern
      functionOptions:
        match: cataas\.com
  path-params-casing:
    description: Path parameters should be snake_case (the dominant convention in this API).
    severity: warn
    given: $.paths[*].parameters[?(@.in=='path')].name
    then:
      function: casing
      functionOptions:
        type: snake
  query-params-casing:
    description: Query parameters should be snake_case (the dominant convention in this API).
    severity: warn
    given: $.paths[*][get,post,put,patch,delete].parameters[?(@.in=='query')]
    then:
      field: name
      function: casing
      functionOptions:
        type: snake
  schema-names-casing:
    description: Component schema names should be PascalCase (the dominant convention in this API).
    severity: warn
    given: $.components.schemas
    then:
      field: '@key'
      function: casing
      functionOptions:
        type: pascal
  schema-properties-casing:
    description: Schema properties should be snake_case (the dominant convention in this API).
    severity: warn
    given: $.components.schemas[*].properties
    then:
      field: '@key'
      function: casing
      functionOptions:
        type: snake
  error-schema-defined:
    description: A shared error schema (ErrorResponse) should be defined for error payloads.
    severity: warn
    given: $.components.schemas
    then:
      field: ErrorResponse
      function: truthy
  no-empty-descriptions:
    description: Descriptions must not be empty strings.
    severity: warn
    given: $..description
    then:
      function: truthy

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