AI SDK OpenCode Harness

The OpenCode harness connects HarnessAgent to OpenCode through a sandboxed bridge.

Native OpenCode configuration

Use openCodeConfig to pass native OpenCode settings that do not have a dedicated adapter option. For example, OpenCode supports selecting a model for an individual agent:

import { createOpenCode } from '@ai-sdk/harness-opencode';

const adapter = createOpenCode({
  openCodeConfig: {
    agent: {
      general: {
        model: 'provider/model-id',
      },
    },
  },
});

Adapter-managed settings take precedence when the same key is present in openCodeConfig. Agent-local permission and deprecated tools settings are ignored so they cannot bypass harness permissions or built-in tool filtering.

Compaction events

Native automatic and manual compaction emit a compaction stream part on completion. Internal summary text is available on that part, rather than streamed as assistant answer text. Summary model usage is preserved.

With includeRawChunks enabled, opencode.compaction raw events expose messageId and status (started or failed). Successful completion uses the normalized compaction part, whose harnessMetadata.opencode.messageId identifies the same operation.

See the AI SDK documentation for usage.