Custom Tensor Adapters
A ModelAdapter is what turns a loaded checkpoint into a Semantic Model Graph - recognizing which weights form an attention block, which form an MLP, whether there's MoE routing or multiple modality towers. Tensormorph ships adapters for common architectures and falls back to a generic adapter for anything unrecognized; writing a custom ModelAdapter is how you get architecture-specific views and correct structural navigation for something the built-in adapters don't cover.
What an adapter is responsible for
- Recognition - inspecting a loaded checkpoint's tensor names, shapes, and any available metadata to decide whether this adapter applies at all.
- Structure building - grouping recognized tensors into the address-space hierarchy (layer, module) rather than leaving them as a flat list.
- Special-casing - flagging structures that unlock dedicated views, most notably MoE routing (for the Expert Galaxy) and multi-tower fusion points (for multimodal models).
Falling back gracefully
An adapter should recognize confidently or not at all - a ModelAdapter that partially misclassifies a structure is worse than one that declines to match and lets the fallback adapter handle it. The fallback adapter's flat structure is always a safe, correct baseline.
Where an adapter runs
A ModelAdapter implements the trait of the same name under the tm-plugin/1 ABI - like any plugin, it can run sandboxed (the default for a third-party adapter) or, if it needs capabilities the sandbox doesn't allow, through the signed native path.
Testing an adapter
Because recognition is the highest-risk part of an adapter (a false-positive match can misrepresent a model's structure), test against both checkpoints your adapter should recognize and checkpoints it should explicitly decline - confirming the fallback adapter still handles the latter correctly is as important as confirming the former.
Related resources
- Model, Architecture, Layer and Module - the address space an adapter builds.
- Extension API - the plugin ABI and trait system an adapter is built against.
- Multimodal Models - an example of the kind of structure a custom adapter would need to recognize.