United States Postal Service · API Governance Rules

United States Postal Service — united states postal service rules

Spectral linting rules defining API design standards and conventions for United States Postal Service.

39 Rules error 13 warn 23 info 3
Generated by API Evangelist Written by API Evangelist tooling for United States Postal Service's APIs. It is a starting point, not a ruleset United States Postal Service publishes or enforces.
View Rules File View on GitHub

Rule Categories

delete error get info microcks no openapi operation parameter paths post query request response schema security servers tags

Rules

error
info-title-required
API title must be present and start with USPS.
$.info.title
warn
info-description-required
API info description must be present and at least 50 characters.
$.info.description
error
info-version-required
API version must be specified.
$.info.version
warn
info-contact-required
API info should include contact information.
$.info.contact
warn
openapi-version
All USPS API specs should use OpenAPI 3.1.0.
$.openapi
error
servers-required
Servers array must be defined.
$.servers
error
servers-https-only
All server URLs must use HTTPS.
$.servers[*].url
warn
servers-description-required
Each server should have a description.
$.servers[*].description
warn
servers-usps-domain
USPS API servers must use apis.usps.com or apis-tem.usps.com domains.
$.servers[*].url
warn
paths-kebab-case
Path segments should use kebab-case.
$.paths[*]~
error
paths-no-trailing-slash
Paths must not end with a trailing slash.
$.paths[*]~
warn
paths-versioned
USPS API paths should include a version segment (e.g., /v3/).
$.paths[*]~
error
operation-summary-required
Every operation must have a summary.
$.paths[*][get,post,put,delete,patch]
warn
operation-summary-title-case
Operation summaries should start with USPS.
$.paths[*][get,post,put,delete,patch].summary
warn
operation-description-required
Every operation must have a description.
$.paths[*][get,post,put,delete,patch]
error
operation-id-required
Every operation must have an operationId.
$.paths[*][get,post,put,delete,patch]
warn
operation-id-camel-case
OperationIds should use camelCase.
$.paths[*][get,post,put,delete,patch].operationId
error
operation-tags-required
Every operation must have at least one tag.
$.paths[*][get,post,put,delete,patch].tags
warn
tags-global-defined
Global tags array should be defined.
$.tags
warn
parameter-description-required
Every parameter must have a description.
$.paths[*][get,post,put,delete,patch].parameters[*]
error
parameter-schema-required
Every parameter must have a schema.
$.paths[*][get,post,put,delete,patch].parameters[*]
warn
request-body-content-json
Request bodies should include application/json content type.
$.paths[*][post,put,patch].requestBody.content
error
response-success-required
Every operation must define at least a 2xx response.
$.paths[*][get,post,put,delete,patch].responses
warn
response-401-required
All authenticated operations should define a 401 response.
$.paths[*][get,post,put,delete,patch].responses
error
response-description-required
Every response must have a description.
$.paths[*][get,post,put,delete,patch].responses[*]
warn
schema-description-required
Top-level schemas should have a description.
$.components.schemas[*]
warn
schema-property-type-required
Schema properties should define a type.
$.components.schemas[*].properties[*]
error
security-schemes-defined
Security schemes must be defined in components.
$.components.securitySchemes
warn
security-bearer-auth
USPS APIs use OAuth 2.0 Bearer Token authentication.
$.components.securitySchemes.bearerAuth
error
get-no-request-body
GET operations must not have a request body.
$.paths[*].get.requestBody
warn
delete-no-request-body
DELETE operations should not have a request body.
$.paths[*].delete.requestBody
warn
post-has-request-body
POST operations creating resources should have a request body.
$.paths[*].post
info
microcks-operation-present
Operations should include x-microcks-operation for mock server compatibility.
$.paths[*][get,post,put,delete,patch]
info
query-params-casing
Query parameters should be camelCase (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
info
schema-properties-casing
Schema properties should be camelCase (the dominant convention in this API).
$.components.schemas[*].properties
warn
error-schema-defined
A shared error schema (Error) should be defined for error payloads.
$.components.schemas
warn
operation-documents-400
Operations should document a 400 response (documented on 83% of this API's operations).
$.paths[*][get,post,put,patch,delete].responses
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
# united-states-postal-service — 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: 8/8 servers on usps.com
#   - query-params-casing: camel @ 43% (n=14)
#   - operationid-casing: camel @ 100% (n=12)
#   - schema-names-casing: pascal @ 100% (n=22)
#   - schema-properties-casing: camel @ 45% (n=94)
#   - security: global (root) — NOT emitting operation-security-required
#   - error-schema-defined: Error
#   - operation-documents-400: 83% adherence
#   - operation-documents-401: 100% adherence
#   - merge: kept 33 existing, added 6 measured, upgraded 0
#   - added: query-params-casing, schema-names-casing, schema-properties-casing, error-schema-defined, operation-documents-400, no-empty-descriptions
extends:
- spectral:oas
rules:
  info-title-required:
    description: API title must be present and start with USPS.
    severity: error
    given: $.info.title
    then:
      function: truthy
  info-description-required:
    description: API info description must be present and at least 50 characters.
    severity: warn
    given: $.info.description
    then:
      function: length
      functionOptions:
        min: 50
  info-version-required:
    description: API version must be specified.
    severity: error
    given: $.info.version
    then:
      function: truthy
  info-contact-required:
    description: API info should include contact information.
    severity: warn
    given: $.info.contact
    then:
      function: truthy
  openapi-version:
    description: All USPS API specs should use OpenAPI 3.1.0.
    severity: warn
    given: $.openapi
    then:
      function: pattern
      functionOptions:
        match: ^3\.1\.
  servers-required:
    description: Servers array must be defined.
    severity: error
    given: $.servers
    then:
      function: truthy
  servers-https-only:
    description: All 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[*].description
    then:
      function: truthy
  servers-usps-domain:
    description: USPS API servers must use apis.usps.com or apis-tem.usps.com domains.
    severity: warn
    given: $.servers[*].url
    then:
      function: pattern
      functionOptions:
        match: apis\.usps\.com
  paths-kebab-case:
    description: Path segments should use kebab-case.
    severity: warn
    given: $.paths[*]~
    then:
      function: pattern
      functionOptions:
        match: ^(/[a-z0-9-{}./]+)+$
  paths-no-trailing-slash:
    description: Paths must not end with a trailing slash.
    severity: error
    given: $.paths[*]~
    then:
      function: pattern
      functionOptions:
        notMatch: /$
  paths-versioned:
    description: USPS API paths should include a version segment (e.g., /v3/).
    severity: warn
    given: $.paths[*]~
    then:
      function: pattern
      functionOptions:
        match: /v[0-9]/
  operation-summary-required:
    description: Every operation must have a summary.
    severity: error
    given: $.paths[*][get,post,put,delete,patch]
    then:
      field: summary
      function: truthy
  operation-summary-title-case:
    description: Operation summaries should start with USPS.
    severity: warn
    given: $.paths[*][get,post,put,delete,patch].summary
    then:
      function: pattern
      functionOptions:
        match: '^USPS '
  operation-description-required:
    description: Every operation must have a description.
    severity: warn
    given: $.paths[*][get,post,put,delete,patch]
    then:
      field: description
      function: truthy
  operation-id-required:
    description: Every operation must have an operationId.
    severity: error
    given: $.paths[*][get,post,put,delete,patch]
    then:
      field: operationId
      function: truthy
  operation-id-camel-case:
    description: OperationIds should use camelCase.
    severity: warn
    given: $.paths[*][get,post,put,delete,patch].operationId
    then:
      function: pattern
      functionOptions:
        match: ^[a-z][a-zA-Z0-9]*$
  operation-tags-required:
    description: Every operation must have at least one tag.
    severity: error
    given: $.paths[*][get,post,put,delete,patch].tags
    then:
      function: truthy
  tags-global-defined:
    description: Global tags array should be defined.
    severity: warn
    given: $.tags
    then:
      function: truthy
  parameter-description-required:
    description: Every parameter must have a description.
    severity: warn
    given: $.paths[*][get,post,put,delete,patch].parameters[*]
    then:
      field: description
      function: truthy
  parameter-schema-required:
    description: Every parameter must have a schema.
    severity: error
    given: $.paths[*][get,post,put,delete,patch].parameters[*]
    then:
      field: schema
      function: truthy
  request-body-content-json:
    description: Request bodies should include application/json content type.
    severity: warn
    given: $.paths[*][post,put,patch].requestBody.content
    then:
      function: truthy
  response-success-required:
    description: Every operation must define at least a 2xx response.
    severity: error
    given: $.paths[*][get,post,put,delete,patch].responses
    then:
      function: truthy
  response-401-required:
    description: All authenticated operations should define a 401 response.
    severity: warn
    given: $.paths[*][get,post,put,delete,patch].responses
    then:
      field: '401'
      function: truthy
  response-description-required:
    description: Every response must have a description.
    severity: error
    given: $.paths[*][get,post,put,delete,patch].responses[*]
    then:
      field: description
      function: truthy
  schema-description-required:
    description: Top-level schemas should have a description.
    severity: warn
    given: $.components.schemas[*]
    then:
      field: description
      function: truthy
  schema-property-type-required:
    description: Schema properties should define a type.
    severity: warn
    given: $.components.schemas[*].properties[*]
    then:
      field: type
      function: truthy
  security-schemes-defined:
    description: Security schemes must be defined in components.
    severity: error
    given: $.components.securitySchemes
    then:
      function: truthy
  security-bearer-auth:
    description: USPS APIs use OAuth 2.0 Bearer Token authentication.
    severity: warn
    given: $.components.securitySchemes.bearerAuth
    then:
      function: truthy
  get-no-request-body:
    description: GET operations must not have a request body.
    severity: error
    given: $.paths[*].get.requestBody
    then:
      function: falsy
  delete-no-request-body:
    description: DELETE operations should not have a request body.
    severity: warn
    given: $.paths[*].delete.requestBody
    then:
      function: falsy
  post-has-request-body:
    description: POST operations creating resources should have a request body.
    severity: warn
    given: $.paths[*].post
    then:
      field: requestBody
      function: truthy
  microcks-operation-present:
    description: Operations should include x-microcks-operation for mock server compatibility.
    severity: info
    given: $.paths[*][get,post,put,delete,patch]
    then:
      field: x-microcks-operation
      function: truthy
  query-params-casing:
    description: Query parameters should be camelCase (the dominant convention in this API).
    severity: info
    given: $.paths[*][get,post,put,patch,delete].parameters[?(@.in=='query')]
    then:
      field: name
      function: pattern
      functionOptions:
        match: ^[a-z][A-Za-z0-9]*$
  schema-names-casing:
    description: Component schema names should be PascalCase (the dominant convention in this API).
    severity: warn
    given: $.components.schemas
    then:
      field: '@key'
      function: pattern
      functionOptions:
        match: ^[A-Z][A-Za-z0-9]*$
  schema-properties-casing:
    description: Schema properties should be camelCase (the dominant convention in this API).
    severity: info
    given: $.components.schemas[*].properties
    then:
      field: '@key'
      function: pattern
      functionOptions:
        match: ^[a-z][A-Za-z0-9]*$
  error-schema-defined:
    description: A shared error schema (Error) should be defined for error payloads.
    severity: warn
    given: $.components.schemas
    then:
      field: Error
      function: truthy
  operation-documents-400:
    description: Operations should document a 400 response (documented on 83% of this API's operations).
    severity: warn
    given: $.paths[*][get,post,put,patch,delete].responses
    then:
      field: '400'
      function: truthy
  no-empty-descriptions:
    description: Descriptions must not be empty strings.
    severity: warn
    given: $..description
    then:
      function: truthy

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