DeepSeek V4-Flash-0731: Codex-compatible coding agents at $0.28 per million tokens (2026)
DeepSeek's V4-Flash-0731 (July 31, 2026) adds native Responses API and an official OpenAI Codex path at $0.14/$0.28 per million tokens. How to wire a coding agent to it, its agent-benchmark scores, and the cost math.
