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openapi: 3.2.0
info:
title: FastRouter Model API
version: 1.0.0
description: OpenAI-compatible LLM gateway API for routing requests across multiple model providers. Model IDs use the provider/model-name format and may support documented suffixes such as :online for web search and :flex for Flex Pricing on compatible models.
servers:
- url: https://api.fastrouter.ai
description: Production API origin
security:
- bearerAuth: []
tags:
- name: Model
paths:
/api/v1/model/selection:
post:
summary: Select a model with Auto Router
externalDocs:
url: https://docs.fastrouter.ai/api-reference/auto-router
requestBody:
$ref: '#/components/requestBodies/JsonRequest'
responses:
'200':
$ref: '#/components/responses/JsonResponse'
tags:
- Model
operationId: postApiV1ModelSelection
x-operation-id-source: derived
/v1/model/selection:
post:
summary: Select a model with Auto Router
description: Alternate path for the Auto Router model selection API.
externalDocs:
url: https://docs.fastrouter.ai/api-reference/auto-router
requestBody:
$ref: '#/components/requestBodies/JsonRequest'
responses:
'200':
$ref: '#/components/responses/JsonResponse'
tags:
- Model
operationId: postV1ModelSelection
x-operation-id-source: derived
components:
responses:
JsonResponse:
description: JSON response
content:
application/json:
schema:
$ref: '#/components/schemas/JsonObject'
schemas:
JsonObject:
type: object
additionalProperties: true
requestBodies:
JsonRequest:
required: true
content:
application/json:
schema:
$ref: '#/components/schemas/JsonObject'
securitySchemes:
bearerAuth:
type: http
scheme: bearer
externalDocs:
description: FastRouter API documentation
url: https://docs.fastrouter.ai