MiniMax H3 Trajectory Checkpoint Save / 轨迹保存 (Advanced)

This is the "save" end of the trajectory checkpoint pair, and its defining feature is in the description: "Atomically saves the first-stage sampled AV latent only after explicit confirmation." Nothing is written unless you flip the switch. If you've been burned by tools that silently dump gigabytes of state, you'll appreciate the paranoia - this node wants to be told, plainly, that saving is what you want.

When you'd use it

It sits after stage 1 of a split trajectory sample (the one that ran the high_sigmas half). You've sampled the coarse pass, the result looks structurally right, and you want to preserve that state so you can either resume it later in this session or move it to another machine/process and finish the fine pass there. This node writes the first-stage latent to disk as a checkpoint, and the matching Load node picks it back up.

The inputs

• trajectory_contract - the H3_T8_TRAJECTORY_PROBE object from the Probe node. This is the binding that makes the checkpoint meaningful: it records which model/sampler/schedule the state belongs to, so a future Load validates against it instead of blindly trusting a file.
• latent - the actual first-stage AV latent from the stage-1 sampler.
• checkpoint_name - a name for the file (default h3_probe).
• confirm_save - default false. Set it to true or nothing gets written. This is the whole safety model.

Outputs:

checkpoint_path (the file path, so you know exactly where it lives - inside the ComfyUI output directory, per the contract) and report_json.

Why "atomic" and "inside the output directory" matter

Atomic means the write is staged and finalized so a crash mid-write can't leave a corrupt checkpoint you'd later load and trust. Confined to the output directory means it can't wander off and write anywhere on your disk - a security property, not an inconvenience.

Installing:

part of MiniMax H3 Audio T8. Manager → "MiniMax H3 Audio T8", or:

cd ComfyUI/custom_nodes
git clone https://github.com/T8mars/comfyui-minimax-h3-audio-T8

Restart. No mandatory pip deps.

The gotcha that bites everyone once

You run the stage-1 sampler, expect a file, find nothing, and it's because confirm_save was still false. That's not a bug - that's the design. Flip it deliberately when you're ready to commit. And keep the limits from the Probe node in mind: this checkpoint is for the T8 dual_clock_euler + native_flow path only, and it saves a completed latent, not a resume-from-mid-forward state. Also relevant if you share checkpoints: H3 local weights are territory-restricted, so "portable state" still assumes you're legally running the model in the first place.