osmAPI Messages API
The Messages API from osmAPI — 1 operation(s) for messages.
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OpenAPI Specification
openapi: 3.2.0
info:
title: osmAPI Anthropic Chat Messages API
description: Anthropic-compatible messages endpoint routed through osmAPI's unified AI gateway. Supports the native Anthropic message format including system prompts, extended thinking, tool use, and streaming.
version: 1.0.0
contact:
name: osmAPI
url: https://www.osmapi.com/
servers:
- url: https://api.osmapi.com/v1
description: Production
security:
- bearerAuth: []
tags:
- name: Messages
paths:
/messages:
post:
operationId: createMessage
summary: Create a message
description: Sends a message request using the Anthropic-compatible format through osmAPI's smart routing system.
requestBody:
required: true
content:
application/json:
schema:
$ref: '#/components/schemas/MessageRequest'
responses:
'200':
description: Successful message response
content:
application/json:
schema:
$ref: '#/components/schemas/MessageResponse'
'429':
description: Rate limit exceeded
content:
application/json:
schema:
$ref: '#/components/schemas/ErrorResponse'
'500':
description: Server error
content:
application/json:
schema:
$ref: '#/components/schemas/ErrorResponse'
tags:
- Messages
components:
schemas:
MessageRequest:
type: object
required:
- model
- messages
- max_tokens
properties:
model:
type: string
description: The model identifier
examples:
- claude-3-5-sonnet-20241022
messages:
type: array
items:
type: object
required:
- role
- content
properties:
role:
type: string
enum:
- user
- assistant
- tool
- function
content:
oneOf:
- type: string
- type: array
items:
type: object
description: Conversation message history
max_tokens:
type: integer
minimum: 1
description: Maximum tokens to generate
system:
oneOf:
- type: string
- type: array
items:
type: object
description: System instructions
temperature:
type: number
minimum: 0
maximum: 1
description: Sampling temperature
tools:
type: array
items:
type: object
description: Available tools for model use
stream:
type: boolean
default: false
description: Enable response streaming
tool_choice:
type: object
description: Tool selection preferences
stop_sequences:
type: array
items:
type: string
description: Custom stop text sequences
top_p:
type: number
minimum: 0
maximum: 1
description: Nucleus sampling parameter
top_k:
type: integer
description: Top-k sampling parameter
thinking:
type: object
description: Extended thinking configuration
metadata:
type: object
description: Request context metadata
service_tier:
type: string
description: Service tier specification
MessageResponse:
type: object
properties:
id:
type: string
type:
type: string
const: message
role:
type: string
const: assistant
model:
type: string
content:
type: array
items:
type: object
properties:
type:
type: string
text:
type: string
thinking:
type: string
stop_reason:
type: string
usage:
type: object
properties:
input_tokens:
type: integer
output_tokens:
type: integer
ErrorResponse:
type: object
properties:
error:
type: object
properties:
message:
type: string
type:
type: string
code:
type: string
securitySchemes:
bearerAuth:
type: http
scheme: bearer
description: Bearer token using osmAPI key (osmint_XXXXXXXXXXXXXXXX)