Get Dtype

Get Dtype Mecha Recipe is the precision twin of Get Device: it takes a recipe and returns the dtype of its tensors - float16, bfloat16, float32, int64, whatever - as a param recipe you can feed back into the graph. In a pack where every parameter is itself a recipe, "what precision is this tensor in?" becomes a first-class value you can route around like any other recipe.

It's a quiet node, and most merges never need it. But it's genuinely useful for two things: adaptive recipes that cast a branch to match whatever a model already is, and debugging - serializing a recipe through it tells you exactly what precision a merge resolved to, which is the first thing to check when a merge looks subtly wrong (fp16 accumulation can do that).

Inputs & output

• a (param) - the recipe to inspect. Output is a param recipe holding the dtype string ("float32", "bfloat16", and so on), which flows into any param socket that accepts a string.

The pack's Mecha Merger already has default_merge_dtype and output_dtype dropdowns covering the normal use ("merge in fp32, output fp16" is a common, sensible pair). So the honest answer to "when do I use this node?" is: when the dtype needs to be derived at runtime rather than picked by hand - e.g., a workflow that reads the precision of a loaded LoRA and asks the merge to match it, so you don't hard-code precision and drift out of sync with your actual files.

Install & gotchas

ComfyUI Manager → search mecha → Mecha Merge Node Pack, or:

cd ComfyUI/custom_nodes
git clone https://github.com/ljleb/comfy-mecha.git
pip install -r comfy-mecha/requirements.txt

Restart; only dependency is sd-mecha==1.1.7.

Notes are short because the node is short. The output is a param recipe - to see it, run it through a Serializer; you can't read it in a plain text widget. And be careful feeding a dtype recipe into a socket that expects a different kind of param (like a float strength): a string where a number belongs will error rather than silently work, which is honestly the best case. If you never touch it, nothing breaks - dtype control on the Merger covers 99% of real workflows.