Home
fline
fline API Rules
fline · API Governance Rules
fline API Rules
Spectral linting rules defining API design standards and conventions for fline.
18 Rules
error 16
warn 1
info 1
Rules by declared severity: the level each rule assigns to a violation. These are not lint results.
Generated by API Evangelist
Written by API Evangelist tooling for fline's APIs. It is a starting point, not a ruleset fline publishes or enforces.
Rule Categories
info
operation
path
response
tag
Rules
info
operation-has-operationid
Every operation declares an operationId (measured: 100% of this contract)
$.paths[*][get,post,put,patch,delete]
warn
operation-has-summary
Every operation has a summary (measured: 100% of this contract)
$.paths[*][get,post,put,patch,delete]
error
operation-has-tags
Every operation is tagged (measured: 100% of this contract)
$.paths[*][get,post,put,patch,delete]
error
operation-has-success-response
Every operation declares a 2xx response (measured: 100% of this contract)
$.paths[*][get,post,put,patch,delete].responses
error
path-no-trailing-slash
Paths carry no trailing slash (measured: 100% of this contract)
$.paths[*]~
error
path-params-in-braces
Path parameters use {braces}, not :colon (measured: 100% of this contract)
$.paths[*]~
error
info-has-description
The contract's info block carries a description (measured: 100% of this contract)
$.info
error
info-title-present
Info declares title (measured: 100% of this contract)
$.info
error
info-description-present
Info declares description (measured: 100% of this contract)
$.info
error
info-version-present
Info declares version (measured: 100% of this contract)
$.info
error
info-version-semver
info.version is numeric (measured: 100% of this contract)
$.info.version
error
tag-name-present
Tag declares name (measured: 100% of this contract)
$.tags[*]
error
tag-name-casing-pascal
Tag.name is pascal case (measured: 100% of this contract)
$.tags[*].name
error
operation-tags-present
Operation declares tags (measured: 100% of this contract)
$.paths[*][get,put,post,delete,patch,options,head,trace]
error
operation-summary-present
Operation declares summary (measured: 100% of this contract)
$.paths[*][get,put,post,delete,patch,options,head,trace]
error
operation-operationid-present
Operation declares operationId (measured: 100% of this contract)
$.paths[*][get,put,post,delete,patch,options,head,trace]
error
operation-responses-present
Operation declares responses (measured: 100% of this contract)
$.paths[*][get,put,post,delete,patch,options,head,trace]
error
response-description-present
Response declares description (measured: 100% of this contract)
$.paths[*][get,put,post,delete,patch,options,head,trace].responses[*]
Spectral Ruleset
# authorship: generated by API Evangelist tooling (derive-rules.py, 2026-11-08). x-method: generated
# Every rule below was MEASURED against fline's own contract before it was written; a rule is present only
# when the contract satisfies it at 80% or more. Severity: 100% -> error, >= 90% -> warn, else info.
# Provenance:
# - operation-has-operationid: 100%
# - operation-has-summary: 100%
# - operation-has-tags: 100%
# - operation-has-success-response: 100%
# - path-no-trailing-slash: 100%
# - path-params-in-braces: 100%
# - info-has-description: 100%
# - info-title-present: 100%
# - info-description-present: 100%
# - info-version-present: 100%
# - info-version-semver: 100%
# - tag-name-present: 100%
# - tag-name-casing-pascal: 100%
# - operation-tags-present: 100%
# - operation-summary-present: 100%
# - operation-operationid-present: 100%
# - operation-responses-present: 100%
# - response-description-present: 100%
x-method: generated
x-generator: derive-rules.py
x-generated: '2026-11-08'
x-source:
- openapi/_ae-authored/fline-sh-openapi-generated.yml
x-self-check:
status: skipped
reason: gate not installed
extends:
- - spectral:oas
- recommended
formats:
- oas3
rules:
operation-has-operationid:
description: 'Every operation declares an operationId (measured: 100% of this contract)'
severity: info
given: $.paths[*][get,post,put,patch,delete]
then:
field: operationId
function: truthy
x-pattern-key: Operation.operationId|present
operation-has-summary:
description: 'Every operation has a summary (measured: 100% of this contract)'
severity: warn
given: $.paths[*][get,post,put,patch,delete]
then:
field: summary
function: truthy
x-pattern-key: Operation.summary|present
operation-has-tags:
description: 'Every operation is tagged (measured: 100% of this contract)'
severity: error
given: $.paths[*][get,post,put,patch,delete]
then:
field: tags
function: truthy
x-pattern-key: Operation.tags|present
operation-has-success-response:
description: 'Every operation declares a 2xx response (measured: 100% of this contract)'
severity: error
given: $.paths[*][get,post,put,patch,delete].responses
then:
function: schema
functionOptions:
schema:
type: object
patternProperties:
^2\d\d$: {}
minProperties: 1
x-pattern-key: Operation.responses|schema:07e20b47
path-no-trailing-slash:
description: 'Paths carry no trailing slash (measured: 100% of this contract)'
severity: error
given: $.paths[*]~
then:
function: pattern
functionOptions:
notMatch: ./$
x-pattern-key: Paths.{key}|pattern:!./$
path-params-in-braces:
description: 'Path parameters use {braces}, not :colon (measured: 100% of this contract)'
severity: error
given: $.paths[*]~
then:
function: pattern
functionOptions:
notMatch: ':'
x-pattern-key: 'Paths.{key}|pattern:!:'
info-has-description:
description: 'The contract''s info block carries a description (measured: 100% of this contract)'
severity: error
given: $.info
then:
field: description
function: truthy
x-pattern-key: Info.description|present
info-title-present:
description: 'Info declares title (measured: 100% of this contract)'
severity: error
given: $.info
then:
field: title
function: defined
x-pattern-key: Info.title|present
info-description-present:
description: 'Info declares description (measured: 100% of this contract)'
severity: error
given: $.info
then:
field: description
function: defined
x-pattern-key: Info.description|present
info-version-present:
description: 'Info declares version (measured: 100% of this contract)'
severity: error
given: $.info
then:
field: version
function: defined
x-pattern-key: Info.version|present
info-version-semver:
description: 'info.version is numeric (measured: 100% of this contract)'
severity: error
given: $.info.version
then:
function: pattern
functionOptions:
match: ^v?\d+(\.\d+)*
x-pattern-key: Info.version|pattern:^v?\d+(\.\d+)*
tag-name-present:
description: 'Tag declares name (measured: 100% of this contract)'
severity: error
given: $.tags[*]
then:
field: name
function: defined
x-pattern-key: Tag.name|present
tag-name-casing-pascal:
description: 'Tag.name is pascal case (measured: 100% of this contract)'
severity: error
given: $.tags[*].name
then:
function: pattern
functionOptions:
match: ^[A-Z][a-zA-Z0-9]*$
x-pattern-key: Tag.name|pattern:^[A-Z][a-zA-Z0-9]*$
operation-tags-present:
description: 'Operation declares tags (measured: 100% of this contract)'
severity: error
given: $.paths[*][get,put,post,delete,patch,options,head,trace]
then:
field: tags
function: defined
x-pattern-key: Operation.tags|present
operation-summary-present:
description: 'Operation declares summary (measured: 100% of this contract)'
severity: error
given: $.paths[*][get,put,post,delete,patch,options,head,trace]
then:
field: summary
function: defined
x-pattern-key: Operation.summary|present
operation-operationid-present:
description: 'Operation declares operationId (measured: 100% of this contract)'
severity: error
given: $.paths[*][get,put,post,delete,patch,options,head,trace]
then:
field: operationId
function: defined
x-pattern-key: Operation.operationId|present
operation-responses-present:
description: 'Operation declares responses (measured: 100% of this contract)'
severity: error
given: $.paths[*][get,put,post,delete,patch,options,head,trace]
then:
field: responses
function: defined
x-pattern-key: Operation.responses|present
response-description-present:
description: 'Response declares description (measured: 100% of this contract)'
severity: error
given: $.paths[*][get,put,post,delete,patch,options,head,trace].responses[*]
then:
field: description
function: defined
x-pattern-key: Response.description|present
Every ruleset here is available over the APIs.io API and to AI agents over MCP.
MCP server
One button, every client — Claude, Cursor, VS Code and the rest.
https://apis.io/mcp
Tools for spectral rules
4 MCP tools reach this
find_rulesBrowse and filter every ruleset in the catalog.
apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
resolveTurn a domain, URL or GitHub org into the provider it belongs to.
find_cohortsEvery scored population of providers in the catalog.
All 92 tools →
Call it yourself
curl for this page
This ruleset
curl "https://apis.io/api/v1/rules/fline-sh-rules"
All spectral rules
curl "https://apis.io/api/v1/rules?limit=25"
Calls without X-API-Key need no key. Calls with it need a paid plan — get a key .
Get an API key
Free tier, no form to fill in. Signing in shares your email address with us — we
store it to create your key and to recognise you if you sign in with another
provider. See our Privacy Policy and
Terms .
A second provider on the same verified email joins the account you already have.