Critic

The most underrated trick in multi-agent AI: make one model argue with another. The Critic node is the designated skeptic of the NodeGPT lineup - a ready-made AutoGen agent whose whole job is to poke holes in what the other agents produced. Pair it with an Engineer and you get the classic "write code, then have someone review it" loop that the pack's example workflow (Task_Solving_with_Code_Generation) is built around.

NodeGPT is Microsoft's AutoGen transplanted into ComfyUI, and its agent nodes are all the same machinery with different system messages baked in. Critic, Engineer, Executor, Planner, Assistant - same Agent output, different personalities. The Critic is the one you add when you realize a single model will happily sign off on its own buggy output.

Inputs and output

• LLM - required. The brain, from any provider node (ChatGPT, LM_Studio, Ollama, llama-cpp, oobaboogaOpenAI).
• Seed / Temp - both default to 0. Zero Temp means it always gives the same take, which is what you want from a reviewer; crank it up only if you want more creative criticism.
• request_timeout - 120s default; raise it if your local model is slow and calls seem to die.

Output: Agent. Wire it into a GroupChat alongside an Engineer, or chain it after a Chat that used a single assistant, to get a second opinion.

The trap to watch

The pack's own history shows why a critic needs an honest Engineer upstream. Community reports from when this was being run described agents that "just repeat whatever is passed to them" - including, presumably, the critiquing agent cheerfully echoing the code it was supposed to tear apart. The author was upfront that the pack was unfinished, and the repo is now deleted: xXAdonesXx/NodeGPT returns 404 and the GitHub account is gone, so the install path below is dead today. If you're rebuilding the idea, the pattern is sound (that's how AutoGen's two-agent reviewer setups work), just build it with a maintained pack.

Installing

cd ComfyUI/custom_nodes
git clone https://github.com/xXAdonesXx/NodeGPT

Restart ComfyUI so requirements (including pyautogen) auto-install, wire LLM → Critic into a GroupChat, and run. Expect to babysit: this pack's chats were known to spin without terminating. In 2026, treat the Critic as a lesson in agent design more than a tool you'd install fresh.