Chat Completions API | Agent Skills Atlas

About this skill

Reference for the OpenAI Chat Completions API (/v1/chat/completions) and legacy /v1/completions as the lingua-franca compatibility protocol — the official spec incl. deprecation timeline and Responses-only feature delta, how 7 local servers (vLLM, SGLang, llama.cpp, Ollama, mistral.rs, Llama Stack/OGX, Lemonade) actually implement it, gateways (LiteLLM, Bifrost), 10 cloud providers' CC-compat endpoints (Anthropic, Gemini, DeepSeek, xAI, Groq, OpenRouter, Azure...), the reasoningcontent/reasoning field schism, finishreason divergences, and client wire behavior (opencode, Vercel AI SDK). NOT for the Responses API (responses-api skill) or Anthropic Messages protocol (messages-api skill).

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Automated security scan: Partial

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0 potential findings · Scanned 11/4/2026 · Scanner 0.2.1

Content SHA-256: 131b4bc18af422ec3f3c971f1586d582d63a6f15641c3359b7e05fd8762dceff

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Original listing metadata

Original name

chat-completions-api

Original description

Reference for the OpenAI Chat Completions API (/v1/chat/completions) and legacy /v1/completions as the lingua-franca compatibility protocol — the official spec incl. deprecation timeline and Responses-only feature delta, how 7 local servers (vLLM, SGLang, llama.cpp, Ollama, mistral.rs, Llama Stack/OGX, Lemonade) actually implement it, gateways (LiteLLM, Bifrost), 10 cloud providers' CC-compat endpoints (Anthropic, Gemini, DeepSeek, xAI, Groq, OpenRouter, Azure...), the reasoning_content/reasoning field schism, finish_reason divergences, and client wire behavior (opencode, Vercel AI SDK). NOT for the Responses API (responses-api skill) or Anthropic Messages protocol (messages-api skill).

About this listing

Category: General
Reported license: MIT
Listing language (estimated): English
Review status: Not individually reviewed
Agent compatibility: Atlas installation supports Claude Code, Codex, and Cursor. Skill-specific dependencies and features are checked during setup.