This Smart-Home Agent Treats Its Own 1B Model as Untrusted Input

Reliability in an AI agent is a harness property, not a model property.

The cleanest proof arrived at the bottom of the model-size ladder: a 688 MB model controlling a smart home, showcased by the model's own maker. The part worth studying is the 25 MB of Rust wrapped around it.

EdgeHome Harness pairs MiniCPM5-1B, 688 MB on disk and about 1 GB at runtime, with a Rust harness between 25 and 64 MB, targeting devices with 2 GB of RAM. A community developer built it; OpenBMB put it on stage. The line everyone will quote is that a full agent stack fits on ultra-constrained edge hardware. The design decision that matters is different: the model is not allowed to do anything.

Everything After the JSON Is Deterministic

EdgeHome Harness is a Rust framework that makes a 1B model act as a reliable smart-home controller. The model only generates a candidate JSON command. Deterministic Rust code validates the schema, resolves devices against a registry, checks capabilities, applies fail-closed policy gates, plans a dry run, and records a replayable trace.