GPT-5.3 Codex API via TokenMix
Use GPT-5.3 Codex from OpenAI as a chat model through the TokenMix AI API relay and multi-model gateway.
GPT-5.3 Codex is OpenAI's most capable agentic coding model, combining frontier coding with reasoning capabilities. It supports configurable reasoning effort and is optimized for long-running agentic tasks.
API access
- Base URL:
https://api.tokenmix.ai/v1 - Model ID:
gpt-5.3-codex - OpenAI SDK compatible. Change the base URL and use your TokenMix API key.
Pricing
Input $1.6975/M tokens, output $13.58/M tokens
Capabilities
Vision, Function calling, JSON mode, Streaming, Reasoning
Model specs
- Context: 400K tokens
- Max output: 128K tokens
Availability
2/2 available API endpoints are healthy right now.
Recent performance
TTFT 2059ms, latency 3347ms, throughput 33.4 tok/s.
Start using this model
Create an API key, top up from $1 when needed, and call this model through the TokenMix OpenAI-compatible endpoint.