> ## Documentation Index
> Fetch the complete documentation index at: https://docs.apiyi.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Seed 2.1 Turbo Chat API リファレンス
> Seed 2.1 Turbo (dola-seed-2-1-turbo-260628) Chat Completions API リファレンスとインタラクティブなプレイグラウンド: OpenAI 互換で、thinking の切り替えと tiers 付きです。
右側のプレイグラウンドを使ってください: `Bearer sk-your-api-key` を **Authorization** に設定します。デフォルトの例では deep thinking が無効（`thinking.disabled`）になっているため、最初の送信で高速に応答が返ります。
このモデルは**deep thinking がデフォルトで ON**です。簡単な質問でも、最初に何百もの reasoning token が生成されます。デバッグ中は、例の `"thinking": {"type": "disabled"}` をそのまま使ってください。実際に推論が必要なときは `reasoning_effort`（low / medium / high）に切り替えます。機能、料金、キャッシュについては、[Seed 2.1 Turbo の概要](/ja/api-capabilities/dola-seed-2-1-turbo/overview)で説明しています。
* thinking を ON にすると、`max_tokens` に余裕を持たせてください（推論は出力バジェットに含まれます）— 3000+ を推奨します
* 綴りが間違ったモデル名では **503**（利用可能なチャネルがありません）が返り、404 ではありません
## パラメータのクイックリファレンス
| パラメータ | 型 | 必須 | デフォルト | 備考 |
| ------------------ | ------ | -- | --------- | -------------------------------------------------------- |
| `model` | string | ✓ | — | 固定: `dola-seed-2-1-turbo-260628` |
| `messages` | array | ✓ | — | 標準のOpenAIメッセージ配列 |
| `max_tokens` | int | | — | 出力予算; 推論オンで3000以上 |
| `thinking.type` | string | | `enabled` | **デフォルトでON**; `disabled`で推論をオフにします |
| `reasoning_effort` | string | | — | `low` / `medium` / `high`; 実測では約226（低）対約960（高）の推論 tokens |
| `stream` | bool | | `false` | SSEストリーミング; 使用状況を追加するには `stream_options.include_usage` |
| `response_format` | object | | — | 構造化出力、`json_schema` + `strict` をサポート |
| `tools` | array | | — | Function-calling ツール一覧 |
## Response Highlights
* thinking をオンにすると、`choices[0].message` には `reasoning_content`（完全な推論テキスト）に加えて `content` も含まれます
* 推論消費量: `usage.completion_tokens_details.reasoning_tokens`
* 暗黙的なキャッシュヒット: `usage.prompt_tokens_details.cached_tokens`（長い先頭部分の繰り返しは 2 回目のリクエストからヒットします）
## OpenAPI
````yaml api-reference/dola-seed-2-1-turbo-chat-openapi-en.yaml POST /v1/chat/completions
openapi: 3.1.0
info:
title: Seed 2.1 Turbo Chat Completions API
description: >
ByteDance Seed 2.1 Turbo (`dola-seed-2-1-turbo-260628`) — OpenAI-compatible
Chat Completions endpoint.
- **Deep thinking is ON by default**: without extra params the model returns
`reasoning_content` and burns extra tokens; pass `thinking: {"type":
"disabled"}` for latency/cost-sensitive calls
- Supports `reasoning_effort` tiers (low / medium / high) to control
thinking depth
- Supports structured output (`response_format: json_schema`), function
calling, and streaming
- Implicit caching is automatic: a repeated long prefix hits `cached_tokens`
from the 2nd request
**Authentication**: add `Authorization: Bearer YOUR_API_KEY` header
**Get an API Key**: create a token in the APIYI console at
`api.apiyi.com/token`
version: 1.0.0
servers:
- url: https://api.apiyi.com
description: Primary endpoint
- url: https://vip.apiyi.com
description: Backup endpoint
security:
- bearerAuth: []
paths:
/v1/chat/completions:
post:
tags:
- Text Generation
summary: Chat completion with Seed 2.1 Turbo
description: >
Run chat completions with `dola-seed-2-1-turbo-260628`, fully
OpenAI-compatible.
- Deep thinking is enabled by default and adds a `reasoning_content`
field; the example disables it for fast debugging
- With thinking enabled, give `max_tokens` generous headroom (reasoning
counts against it)
operationId: createSeedChatCompletion
requestBody:
required: true
content:
application/json:
schema:
$ref: '#/components/schemas/SeedChatRequest'
example:
model: dola-seed-2-1-turbo-260628
messages:
- role: user
content: Introduce yourself in one sentence
max_tokens: 500
thinking:
type: disabled
responses:
'200':
description: Chat completion succeeded
content:
application/json:
schema:
$ref: '#/components/schemas/SeedChatResponse'
'400':
description: Invalid parameters (e.g. malformed json_schema, wrong types)
'401':
description: Unauthorized - invalid API Key
'429':
description: Rate limit exceeded or insufficient balance
'503':
description: >-
Wrong model name or no available channel for your group (this model
returns 503 instead of 404 for unknown model names)
security:
- bearerAuth: []
components:
schemas:
SeedChatRequest:
type: object
required:
- model
- messages
properties:
model:
type: string
description: Model ID, fixed to dola-seed-2-1-turbo-260628
enum:
- dola-seed-2-1-turbo-260628
default: dola-seed-2-1-turbo-260628
messages:
type: array
description: Conversation messages, standard OpenAI format
items:
type: object
required:
- role
- content
properties:
role:
type: string
description: Message role
enum:
- system
- user
- assistant
- tool
content:
type: string
description: Message content
max_tokens:
type: integer
description: >-
Max output tokens. Reasoning counts against this too - give it
headroom (e.g. 2000+) when thinking is on
default: 500
thinking:
type: object
description: >-
Deep-thinking switch. ON by default; pass {"type": "disabled"} to
turn it off and cut latency and output tokens sharply
properties:
type:
type: string
enum:
- enabled
- disabled
default: disabled
reasoning_effort:
type: string
description: >-
Thinking depth tier (do not combine with thinking.disabled).
Measured: low ~226, high ~960 reasoning tokens
enum:
- low
- medium
- high
stream:
type: boolean
description: >-
Stream via SSE. Combine with stream_options.include_usage to get
usage in the final chunk
default: false
temperature:
type: number
description: Sampling temperature
response_format:
type: object
description: >-
Structured output. Supports {"type": "json_schema", "json_schema":
{name, strict, schema}}
tools:
type: array
description: Function-calling tool list, standard OpenAI format
items:
type: object
SeedChatResponse:
type: object
properties:
id:
type: string
description: Request ID
model:
type: string
choices:
type: array
description: >-
Completion results. Besides content, message carries
reasoning_content when thinking is on
items:
type: object
usage:
type: object
description: >-
Usage. completion_tokens_details.reasoning_tokens = thinking spend;
prompt_tokens_details.cached_tokens = implicit cache hits
securitySchemes:
bearerAuth:
type: http
scheme: bearer
description: API Key from the APIYI console
````