Altimate AI Chat API
The Chat API from Altimate AI — 1 operation(s) for chat.
OpenAPI Specification
openapi: 3.1.0
info:
title: Fast ACCOUNT_COSTS Chat API
version: 0.1.0
tags:
- name: Chat
paths:
/agents/v1/chat/completions:
post:
tags:
- Chat
summary: Create Chat Completion
description: 'Create a chat completion (OpenAI-compatible).
Uses litellm with provider fallback: Azure GPT-5.5 → Anthropic Sonnet 4.6.
The model in the request is ignored — provider selection is automatic.'
operationId: create_chat_completion_agents_v1_chat_completions_post
security:
- HTTPBearer: []
- HTTPBearer: []
parameters:
- name: x-session-id
in: header
required: false
schema:
anyOf:
- type: string
maxLength: 255
- type: 'null'
description: Optional opaque conversation identifier. When provided, the call's Langfuse trace is grouped under this session_id, letting a multi-turn agentic conversation appear as one timeline. Clients should pass the same value across every turn of a single conversation.
title: X-Session-Id
description: Optional opaque conversation identifier. When provided, the call's Langfuse trace is grouped under this session_id, letting a multi-turn agentic conversation appear as one timeline. Clients should pass the same value across every turn of a single conversation.
requestBody:
required: true
content:
application/json:
schema:
$ref: '#/components/schemas/ChatRequest'
responses:
'200':
description: Successful Response
content:
application/json:
schema: {}
'422':
description: Validation Error
content:
application/json:
schema:
$ref: '#/components/schemas/HTTPValidationError'
components:
schemas:
ResponseFunction:
properties:
name:
anyOf:
- type: string
- type: 'null'
title: Name
arguments:
type: string
title: Arguments
type: object
required:
- arguments
title: ResponseFunction
Function:
properties:
name:
type: string
title: Name
description:
anyOf:
- type: string
- type: 'null'
title: Description
parameters:
title: Parameters
type: object
required:
- name
- parameters
title: Function
SystemMessage:
properties:
name:
anyOf:
- type: string
- type: 'null'
title: Name
role:
type: string
const: system
title: Role
default: system
content:
anyOf:
- type: string
- items:
$ref: '#/components/schemas/TextContent'
type: array
title: Content
type: object
required:
- content
title: SystemMessage
StreamOptions:
properties:
include_usage:
type: boolean
title: Include Usage
default: true
type: object
title: StreamOptions
ToolCall:
properties:
index:
anyOf:
- type: integer
- type: 'null'
title: Index
id:
anyOf:
- type: string
- type: 'null'
title: Id
type:
type: string
const: function
title: Type
default: function
function:
$ref: '#/components/schemas/ResponseFunction'
type: object
required:
- function
title: ToolCall
UserMessage:
properties:
name:
anyOf:
- type: string
- type: 'null'
title: Name
role:
type: string
const: user
title: Role
default: user
content:
anyOf:
- type: string
- items:
anyOf:
- $ref: '#/components/schemas/TextContent'
- $ref: '#/components/schemas/ImageContent'
type: array
title: Content
type: object
required:
- content
title: UserMessage
HTTPValidationError:
properties:
detail:
items:
$ref: '#/components/schemas/ValidationError'
type: array
title: Detail
type: object
title: HTTPValidationError
ValidationError:
properties:
loc:
items:
anyOf:
- type: string
- type: integer
type: array
title: Location
msg:
type: string
title: Message
type:
type: string
title: Error Type
type: object
required:
- loc
- msg
- type
title: ValidationError
ImageContent:
properties:
type:
type: string
const: image_url
title: Type
default: image
image_url:
$ref: '#/components/schemas/ImageUrl'
cache_control:
anyOf:
- additionalProperties: true
type: object
- type: 'null'
title: Cache Control
type: object
required:
- image_url
title: ImageContent
Tool:
properties:
type:
type: string
const: function
title: Type
default: function
function:
$ref: '#/components/schemas/Function'
type: object
required:
- function
title: Tool
ImageUrl:
properties:
url:
type: string
title: Url
detail:
anyOf:
- type: string
- type: 'null'
title: Detail
default: auto
type: object
required:
- url
title: ImageUrl
ToolMessage:
properties:
role:
type: string
const: tool
title: Role
default: tool
content:
anyOf:
- type: string
- items:
$ref: '#/components/schemas/ToolContent'
type: array
- items:
additionalProperties: true
type: object
type: array
title: Content
tool_call_id:
type: string
title: Tool Call Id
type: object
required:
- content
- tool_call_id
title: ToolMessage
ToolContent:
properties:
type:
type: string
const: text
title: Type
default: text
text:
type: string
title: Text
type: object
required:
- text
title: ToolContent
ChatRequest:
properties:
messages:
items:
anyOf:
- $ref: '#/components/schemas/SystemMessage'
- $ref: '#/components/schemas/UserMessage'
- $ref: '#/components/schemas/AssistantMessage'
- $ref: '#/components/schemas/ToolMessage'
type: array
title: Messages
model:
type: string
title: Model
default: custom
frequency_penalty:
anyOf:
- type: number
maximum: 2.0
minimum: -2.0
- type: 'null'
title: Frequency Penalty
default: 0.0
presence_penalty:
anyOf:
- type: number
maximum: 2.0
minimum: -2.0
- type: 'null'
title: Presence Penalty
default: 0.0
stream:
anyOf:
- type: boolean
- type: 'null'
title: Stream
default: false
stream_options:
anyOf:
- $ref: '#/components/schemas/StreamOptions'
- type: 'null'
temperature:
anyOf:
- type: number
maximum: 2.0
minimum: 0.0
- type: 'null'
title: Temperature
default: 1.0
top_p:
anyOf:
- type: number
maximum: 1.0
minimum: 0.0
- type: 'null'
title: Top P
default: 1.0
user:
anyOf:
- type: string
- type: 'null'
title: User
max_tokens:
anyOf:
- type: integer
- type: 'null'
title: Max Tokens
default: 2048
max_completion_tokens:
anyOf:
- type: integer
- type: 'null'
title: Max Completion Tokens
reasoning_effort:
anyOf:
- type: string
enum:
- low
- medium
- high
- type: 'null'
title: Reasoning Effort
n:
anyOf:
- type: integer
- type: 'null'
title: N
default: 1
tools:
anyOf:
- items:
$ref: '#/components/schemas/Tool'
type: array
- type: 'null'
title: Tools
tool_choice:
anyOf:
- type: string
- {}
title: Tool Choice
default: auto
stop:
anyOf:
- items:
type: string
type: array
- type: string
- type: 'null'
title: Stop
extra_body:
anyOf:
- additionalProperties: true
type: object
- type: 'null'
title: Extra Body
type: object
required:
- messages
title: ChatRequest
AssistantMessage:
properties:
name:
anyOf:
- type: string
- type: 'null'
title: Name
role:
type: string
const: assistant
title: Role
default: assistant
content:
anyOf:
- type: string
- items:
anyOf:
- $ref: '#/components/schemas/TextContent'
- $ref: '#/components/schemas/ImageContent'
type: array
- type: 'null'
title: Content
tool_calls:
anyOf:
- items:
$ref: '#/components/schemas/ToolCall'
type: array
- type: 'null'
title: Tool Calls
type: object
title: AssistantMessage
TextContent:
properties:
type:
type: string
const: text
title: Type
default: text
text:
type: string
title: Text
cache_control:
anyOf:
- additionalProperties: true
type: object
- type: 'null'
title: Cache Control
type: object
required:
- text
title: TextContent
securitySchemes:
HTTPBearer:
type: http
scheme: bearer