ComfyUI Direct API — Technical Reference

The direct API is the execution layer. MCP handles discovery; this handles everything else.

Server Discovery

Always probe before use. Both ports are interchangeable — either may be up or down.

curl -s --max-time 3 http://localhost:8188/api/system_stats
curl -s --max-time 3 http://localhost:8189/api/system_stats

Core Endpoints