deepseek-harness/packages/code-runtime

code-runtime/ — code-execution capability family

The code-execution capability seam (see capability seams): an abstract runtime interface for executing one model-written program against host-provided async bindings, capturing what it printed and returned. The consumer is the tool registry's Code Mode, specified alongside the seam in the Code Mode RFC. Product packages.

Package	Role	ctx key
code-runtime/	Abstract code-execution seam (interface + vocabulary)	ctx.codeRuntime
code-runtime-worker/	Worker-thread backend: fresh worker per run, TypeScript via host-side type-strip, port-bridged bindings, budget/heap containment	registers ctx.codeRuntime

The interface lives at code-runtime/code-runtime/; the shipped backend at code-runtime/code-runtime-worker/. Backends differ by execution substrate (worker thread, process, container) and by source language — both readonly descriptors on the service — and register ctx.codeRuntime without touching the interface or its consumer; that split is what makes a hardened backend a drop-in later.