DeepSeek API Integration: OpenAI & Anthropic Formats

DeepSeek's API is uniquely dual-format — it supports both OpenAI-compatible endpoints and Anthropic API format. This means you can use the OpenAI SDK with base_url=https://api.deepseek.com or the Anthropic SDK with base_url=https://api.deepseek.com/anthropic. Migration from either ecosystem is typically a single-line change.

But integration depth varies. The Anthropic format supports thinking mode, tool calls, and streaming — but ignores budget_tokens for thinking and cache_control. The OpenAI format supports JSON mode, FIM completion, and streaming. Tool calls in thinking mode have unique constraints around reasoning_content management. The pages in this section cover the full integration landscape.

What You'll Find Here

OpenAI-Compatible API

SDK configuration for OpenAI, LangChain, and other compatible tooling. Anthropic API format for Claude ecosystem tools. Migration patterns from both platforms. Streaming differences and keep-alive handling.

Tool Calls with Thinking

Combining tools and reasoning in DeepSeek. The mandatory reasoning_content passback rule for tool-call loops. strict mode (beta) for JSON schema enforcement in function calls. Error handling and 400 avoidance patterns.