deepseek-harness/packages/code-runtime

description	kind
Package map for the code-execution capability family: what program execution does for you, and which package owns each part.	package-group

code-runtime/ — code-execution capability family

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Summary

The code-runtime/ group provides program execution: a model writes one program that calls host-provided functions as ordinary async calls, and a runtime executes it in isolation and returns only what the program printed and returned. One package defines the shared capability (ctx.codeRuntime), a second executes TypeScript programs in a fresh Node worker thread, and a third owns the wire protocol between a Node host and a CPython subprocess for the Python backend. Every run is independent — no state carries from one program to the next — and failures come back as part of the result, so the caller can see why a program failed and feed that back to the model.

Table of Contents

• Packages
• Related documentation
• Dev Note

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Packages

These three packages together provide program execution; each README describes what its part does.

Package	Role	ctx key
code-runtime/	Defines what a code runtime does: run one program against host-provided bindings and report what it printed and returned	ctx.codeRuntime
code-runtime-worker-thread/	Executes TypeScript programs, each in a fresh Node worker thread	registers ctx.codeRuntime
code-runtime-python/	Owns the fd-3 wire protocol between a Node host and a CPython subprocess, the Python backend's protocol layer	—

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Related documentation

Start with the subsystem reference for the service contract, then the PTC mode design that consumes this capability and the capability-seam model it follows.

• Code runtime subsystem reference — request/result vocabulary, bindings, and the ctx.codeRuntime cordis surface.
• PTC mode Agent Note — how the tool registry presents run_code to the model.
• Capability seams — the Service Definition / Service Provider / Consumer split this family follows.

Dev Note

Working context for maintainers — click to expand

None.