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Harness Kernel Harness Kernel

@harness-kernel/core

@harness-kernel/core is the stable center of Harness Kernel. It has zero external runtime dependencies and exposes both agent-space and runtime-host contracts.

Use it for:

  • defineAgent, HarnessMode, HarnessTool, HarnessHook, HarnessRole, HarnessContextProvider, and HarnessEvent;
  • createHarnessSessionStore and createHarnessSession;
  • model provider contracts and registry helpers;
  • storage and sandbox contracts plus MemorySessionStorage, legacy run storage helpers, and NoopSandbox;
  • logging contracts plus ConsoleLogSink and MemoryLogSink;
  • official schema primitives from @harness-kernel/core/schema.

Preferred imports:

import { defineAgent } from "@harness-kernel/core/agent";
import { HarnessMode } from "@harness-kernel/core/agent/mode";
import { createHarnessSessionStore } from "@harness-kernel/core/runner";
import { s } from "@harness-kernel/core/schema";

See Package Boundaries and API Reference.