gpt-oss-120b, an open-weight reasoning model built by OpenAI, is now available on Telnyx Inference in beta, hosted on Telnyx-owned GPUs in US regions.
model=openai/gpt-oss-120b in the OpenAI built gpt-oss-120b in the US and released it as open weights, and Telnyx serves it on Telnyx-owned GPUs inside the United States. Because we own the infrastructure, adding models like this is fast and pricing stays at a fraction of proprietary APIs.
The model documentation positions gpt-oss-120b for open-weight reasoning. With a 128K context window and configurable reasoning effort, it fits reasoning-heavy workloads like document analysis and agentic planning, and teams already running OpenAI-compatible clients can switch the base URL to Telnyx without changing their code.
curl -X POST https://api.telnyx.com/v2/ai/openai/chat/completions \
-H "Authorization: Bearer $TELNYX_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "openai/gpt-oss-120b",
"messages": [
{"role": "user", "content": "Prove that the square root of 2 is irrational."}
]
}'
Learn more in the model documentation.