> ## Documentation Index > Fetch the complete documentation index at: https://docs.evolink.ai/llms.txt > Use this file to discover all available pages before exploring further. # Doubao Seed 2.0 - Quick Start > - Call Doubao Seed 2.0 series models using OpenAI SDK format - Synchronous processing mode, returns chat content in real time - Minimized parameters for quick start - Supported models: `doubao-seed-2.0-pro`, `doubao-seed-2.0-lite`, `doubao-seed-2.0-mini`, `doubao-seed-2.0-code` - 💡 Need more features? See [Full Parameter Documentation](./doubao-seed-2.0-reference) **BaseURL**: The default BaseURL is `https://direct.evolink.ai`, which has better support for text models and long-lived connections. `https://api.evolink.ai` is the primary endpoint for multimodal services and serves as a fallback address for text models. ## OpenAPI ````yaml /en/api-manual/language-series/doubao-seed-2.0/doubao-seed-2.0-quickstart.json POST /v1/chat/completions openapi: 3.1.0 info: title: Doubao Seed 2.0 Quick Start description: >- Get started with the Doubao Seed 2.0 chat API, complete your first AI chat call in 5 minutes license: name: MIT version: 1.0.0 servers: - url: https://direct.evolink.ai description: Production (recommended) - url: https://api.evolink.ai description: Alternative URL security: - bearerAuth: [] tags: - name: Chat Completion description: AI chat completion related APIs paths: /v1/chat/completions: post: tags: - Chat Completion summary: Doubao Seed 2.0 Quick Chat description: >- - Call Doubao Seed 2.0 series models using OpenAI SDK format - Synchronous processing mode, returns chat content in real time - Minimized parameters for quick start - Supported models: `doubao-seed-2.0-pro`, `doubao-seed-2.0-lite`, `doubao-seed-2.0-mini`, `doubao-seed-2.0-code` - 💡 Need more features? See [Full Parameter Documentation](./doubao-seed-2.0-reference) operationId: createChatCompletionQuickDoubaoSeed20 requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/ChatCompletionQuickRequest' responses: '200': description: Chat completion successful content: application/json: schema: $ref: '#/components/schemas/ChatCompletionResponse' '400': description: Invalid request parameters content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: code: 400 message: Invalid request parameters type: invalid_request_error '401': description: Unauthenticated, invalid or expired token content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: code: 401 message: Invalid or expired token type: authentication_error '402': description: Insufficient quota, recharge required content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: code: 402 message: Insufficient quota type: insufficient_quota_error fallback_suggestion: https://evolink.ai/dashboard/billing '403': description: Access denied content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: code: 403 message: Access denied for this model type: permission_error param: model '404': description: Resource not found content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: code: 404 message: Specified model not found type: not_found_error param: model fallback_suggestion: doubao-seed-2.0-pro '429': description: Rate limit exceeded content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: code: 429 message: Rate limit exceeded type: rate_limit_error fallback_suggestion: retry after 60 seconds '500': description: Internal server error content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: code: 500 message: Internal server error type: internal_server_error fallback_suggestion: try again later '502': description: Upstream service error content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: code: 502 message: Upstream AI service unavailable type: upstream_error fallback_suggestion: try different model '503': description: Service temporarily unavailable content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: error: code: 503 message: Service temporarily unavailable type: service_unavailable_error fallback_suggestion: retry after 30 seconds components: schemas: ChatCompletionQuickRequest: type: object required: - model - messages properties: model: type: string description: >- Chat model name - `doubao-seed-2.0-pro`: Flagship, strongest overall capability, ideal for complex reasoning and high-quality generation - `doubao-seed-2.0-lite`: Lightweight, faster speed, cost-effective - `doubao-seed-2.0-mini`: Ultra-fast, quickest response, suitable for simple tasks - `doubao-seed-2.0-code`: Code-specialized, optimized for code generation and understanding enum: - doubao-seed-2.0-pro - doubao-seed-2.0-lite - doubao-seed-2.0-mini - doubao-seed-2.0-code default: doubao-seed-2.0-pro example: doubao-seed-2.0-pro messages: type: array description: Chat message list items: $ref: '#/components/schemas/MessageSimple' minItems: 1 example: - role: user content: Hello, introduce the new features of Doubao Seed 2.0 ChatCompletionResponse: type: object properties: id: type: string description: Unique identifier of chat completion example: 0217714854126607f5a9cf8ed5b018c76e4ad3dc2810db57ffb50 model: type: string description: Actual model name used example: doubao-seed-2-0-pro-260215 object: type: string enum: - chat.completion description: Response type example: chat.completion created: type: integer description: Creation timestamp example: 1771485416 service_tier: type: string description: |- Service tier for this request - `default`: Default service tier - `scale`: Used reserved quota enum: - default - scale example: default choices: type: array description: Chat completion choices list items: $ref: '#/components/schemas/Choice' usage: $ref: '#/components/schemas/Usage' ErrorResponse: type: object properties: error: type: object properties: code: type: integer description: HTTP status error code message: type: string description: Error description type: type: string description: Error type param: type: string description: Related parameter name fallback_suggestion: type: string description: Suggested solution MessageSimple: type: object required: - role - content properties: role: type: string description: Message role enum: - user content: type: string description: Message content (plain text) Choice: type: object properties: index: type: integer description: Choice index example: 0 message: $ref: '#/components/schemas/AssistantMessage' finish_reason: type: string description: Finish reason enum: - stop - length - content_filter example: stop moderation_hit_type: type: string nullable: true description: >- When model output contains sensitive content, returns the matched risk classification label - `severe_violation`: Model output involves severe violation - `violence`: Model output involves violent behavior enum: - severe_violation - violence Usage: type: object description: Token usage statistics properties: prompt_tokens: type: integer description: Input token count example: 15 completion_tokens: type: integer description: Output token count example: 256 total_tokens: type: integer description: Total token count example: 271 prompt_tokens_details: type: object description: Input token details properties: cached_tokens: type: integer description: Cached token count example: 0 completion_tokens_details: type: object description: Output token details properties: reasoning_tokens: type: integer description: Reasoning/chain-of-thought token count example: 0 AssistantMessage: type: object properties: role: type: string description: Role of the message sender enum: - assistant example: assistant content: type: string description: AI response message content example: >- Hello! Doubao Seed 2.0 is ByteDance's next-generation large language model, featuring enhanced reasoning, multimodal understanding, and deep thinking capabilities... securitySchemes: bearerAuth: type: http scheme: bearer description: >- ##All APIs require Bearer Token authentication## **Get API Key:** Visit the [API Key Management Page](https://evolink.ai/dashboard/keys) to get your API Key **Add to request header:** ``` Authorization: Bearer YOUR_API_KEY ``` ````