rules:

  # ─── INFO / METADATA ───────────────────────────────────────────────────────

  info-title-required:
    message: API info title is required
    severity: error
    given: $.info
    then:
      field: title
      function: truthy

  info-title-contains-unified:
    message: API title should reference Unified.to
    severity: warn
    given: $.info.title
    then:
      function: pattern
      functionOptions:
        match: "(?i)unified"

  info-description-required:
    message: API info description is required
    severity: warn
    given: $.info
    then:
      field: description
      function: truthy

  info-version-required:
    message: API info version is required
    severity: error
    given: $.info
    then:
      field: version
      function: truthy

  # ─── OPENAPI VERSION ────────────────────────────────────────────────────────

  openapi-version-3:
    message: OpenAPI version must be 3.x
    severity: error
    given: $
    then:
      field: openapi
      function: pattern
      functionOptions:
        match: "^3\\."

  # ─── SERVERS ────────────────────────────────────────────────────────────────

  servers-defined:
    message: At least one server must be defined
    severity: error
    given: $
    then:
      field: servers
      function: truthy

  servers-https-only:
    message: Server URLs must use HTTPS
    severity: error
    given: $.servers[*].url
    then:
      function: pattern
      functionOptions:
        match: "^https://"

  servers-unified-to-domain:
    message: Server should be on api.unified.to or regional subdomain
    severity: info
    given: $.servers[*].url
    then:
      function: pattern
      functionOptions:
        match: "unified\\.to"

  # ─── PATHS — NAMING CONVENTIONS ─────────────────────────────────────────────

  paths-connection-id-required:
    message: API resource paths should include {connection_id} parameter
    severity: warn
    given: $.paths[*]~
    then:
      function: pattern
      functionOptions:
        match: "^/(unified|[a-z]+/\\{connection_id\\})"

  paths-kebab-case:
    message: Path segments should use snake_case or kebab-case (Unified.to convention)
    severity: warn
    given: $.paths[*]~
    then:
      function: pattern
      functionOptions:
        match: "^(/[a-z0-9_{}/-]+)+$"

  paths-no-trailing-slash:
    message: Paths must not end with a trailing slash
    severity: warn
    given: $.paths[*]~
    then:
      function: pattern
      functionOptions:
        notMatch: "/$"

  # ─── OPERATIONS ─────────────────────────────────────────────────────────────

  operation-id-required:
    message: Every operation must have an operationId
    severity: error
    given: $.paths[*][get,post,put,patch,delete,head,options]
    then:
      field: operationId
      function: truthy

  operation-summary-required:
    message: Every operation must have a summary
    severity: error
    given: $.paths[*][get,post,put,patch,delete,head,options]
    then:
      field: summary
      function: truthy

  operation-summary-title-case:
    message: Operation summaries should use Title Case
    severity: warn
    given: $.paths[*][get,post,put,patch,delete,head,options].summary
    then:
      function: pattern
      functionOptions:
        match: "^[A-Z]"

  operation-tags-required:
    message: Every operation should have at least one tag
    severity: warn
    given: $.paths[*][get,post,put,patch,delete,head,options]
    then:
      field: tags
      function: truthy

  operation-description-required:
    message: Every operation should have a description
    severity: info
    given: $.paths[*][get,post,put,patch,delete,head,options]
    then:
      field: description
      function: truthy

  # ─── PARAMETERS ─────────────────────────────────────────────────────────────

  parameter-connection-id-path:
    message: connection_id path parameter should be defined when present
    severity: error
    given: $.paths[*][get,post,put,patch,delete].parameters[?(@.name=='connection_id')]
    then:
      field: in
      function: enumeration
      functionOptions:
        values:
          - path

  parameter-description-required:
    message: All parameters should have descriptions
    severity: warn
    given: $.paths[*][get,post,put,patch,delete].parameters[*]
    then:
      field: description
      function: truthy

  parameter-pagination-limit:
    message: List operations should support a limit parameter
    severity: info
    given: $.paths[*].get.parameters[?(@.name=='limit')]
    then:
      field: schema.type
      function: enumeration
      functionOptions:
        values:
          - integer
          - number

  parameter-snake-case:
    message: Parameter names should use snake_case (Unified.to convention)
    severity: warn
    given: $.paths[*][get,post,put,patch,delete].parameters[*].name
    then:
      function: pattern
      functionOptions:
        match: "^[a-z][a-z0-9_]*$"

  # ─── REQUEST BODIES ──────────────────────────────────────────────────────────

  request-body-json:
    message: Request bodies should use application/json content type
    severity: warn
    given: $.paths[*][post,put,patch].requestBody.content
    then:
      function: schema
      functionOptions:
        schema:
          type: object
          minProperties: 1

  # ─── RESPONSES ───────────────────────────────────────────────────────────────

  response-success-defined:
    message: Every operation must define at least one 2xx success response
    severity: error
    given: $.paths[*][get,post,put,patch,delete]
    then:
      field: responses
      function: truthy

  response-description-required:
    message: All responses must have a description
    severity: error
    given: $.paths[*][get,post,put,patch,delete].responses[*]
    then:
      field: description
      function: truthy

  response-401-unauthorized:
    message: Protected operations should define 401 Unauthorized response
    severity: warn
    given: $.paths[*][get,post,put,patch,delete]
    then:
      field: responses.401
      function: truthy

  response-422-validation:
    message: Write operations should define a 422 validation error response
    severity: info
    given: $.paths[*][post,put,patch]
    then:
      field: responses.422
      function: truthy

  # ─── SCHEMAS — PROPERTY NAMING ───────────────────────────────────────────────

  schema-property-snake-case:
    message: Schema properties should use snake_case (Unified.to convention)
    severity: warn
    given: $.components.schemas[*].properties[*]~
    then:
      function: pattern
      functionOptions:
        match: "^[a-z][a-z0-9_]*$"

  schema-raw-property-present:
    message: Domain model schemas should include a 'raw' property for provider-specific data
    severity: info
    given: $.components.schemas[?(@.type=='object')]
    then:
      field: properties.raw
      function: truthy

  # ─── SECURITY ────────────────────────────────────────────────────────────────

  security-schemes-defined:
    message: Security schemes must be defined
    severity: error
    given: $.components
    then:
      field: securitySchemes
      function: truthy

  security-jwt-bearer:
    message: Unified.to uses JWT bearer token authentication
    severity: warn
    given: $.components.securitySchemes[*][?(@.type=='http')]
    then:
      field: scheme
      function: enumeration
      functionOptions:
        values:
          - bearer

  # ─── HTTP METHOD CONVENTIONS ─────────────────────────────────────────────────

  get-no-request-body:
    message: GET operations must not have a request body
    severity: error
    given: $.paths[*].get
    then:
      field: requestBody
      function: falsy

  delete-returns-200-or-204:
    message: DELETE operations should return 200 (with body) or 204 (no content)
    severity: info
    given: $.paths[*].delete.responses
    then:
      function: schema
      functionOptions:
        schema:
          type: object
          minProperties: 1

  # ─── GENERAL QUALITY ─────────────────────────────────────────────────────────

  no-empty-descriptions:
    message: Descriptions must not be empty strings
    severity: warn
    given: $..description
    then:
      function: pattern
      functionOptions:
        match: ".+"

  components-schemas-defined:
    message: Components schemas section should be defined for reusable types
    severity: error
    given: $.components
    then:
      field: schemas
      function: truthy

  schema-raw-passthrough:
    message: >-
      Each domain model should have a 'raw' passthrough object for provider-specific
      fields not covered by the unified schema.
    severity: info
    given: $.components.schemas[?(!@.title)]
    then:
      function: truthy