Base URLs and protocols
Use the Essevin API host and choose the OpenAI or Anthropic path required by the client.
Essevin uses the Essevin consumer API host. The protocol depends on the client and model family, not the key format.
| Scenario | Protocol | Base URL |
|---|---|---|
| Claude Code, Anthropic SDK, Claude models | Anthropic | https://api.essevin.com |
| Codex CLI | OpenAI Responses | https://api.essevin.com/v1 |
| GPT and Gemini chat | OpenAI Chat Completions | https://api.essevin.com/v1 |
| GPT Image and Gemini image models | OpenAI Images | https://api.essevin.com/v1 |
Common endpoints
| Capability | Endpoint |
|---|---|
| Model discovery | GET /v1/models |
| OpenAI chat | POST /v1/chat/completions |
| OpenAI Responses | POST /v1/responses |
| Anthropic Messages | POST /v1/messages |
| Image generation | POST /v1/images/generations |
| Image editing | POST /v1/images/edits when supported by the selected model |
A Claude key configured as OpenAI Compatible reaches the wrong protocol path and returns 404. Select Anthropic and remove /v1 from the Base URL.