When you work across multiple features, OpenCode's default compaction doesn't know how to distinguish active work from older discussions, so it gives them equal priority. This can make important current details easy to lose.

Customize OpenCode's compaction prompt for priority-aware compaction, deciding which messages are prioritized or discarded in the next session. Specify which discussions to discard and which decisions, files, and snippets to prioritize in the summary.

GitHub · npm

Install

opencode plugin -g opencode-plugin-compaction-prompt

This installs the plugin in your global OpenCode configuration. To install it for one project only, omit -g.

You can also add it manually to your global opencode.jsonc:

{
  "$schema": "https://opencode.ai/config.json",
  "plugin": [
    [
      "opencode-plugin-compaction-prompt",
      {
        "memoryFile": ".opencode/compaction.md",
        "mode": "append",
        "completionMarker": "opencode-plugin-compaction-prompt: Custom compaction done."
      }
    ]
  ]
}

Create .opencode/compaction.md in the project when you have project-specific context to preserve. The file is optional.

Options

Option	Default	Description
`memoryFile`	`.opencode/compaction.md`	File resolved relative to the active worktree.
`mode`	`append`	Append instructions to OpenCode's default prompt, or use `replace` to provide a complete prompt.
`prompt`	"" (empty)	Additional instructions used together with `memoryFile`; both are included in the compaction instructions.
`completionMarker`	`opencode-plugin-compaction-prompt: Custom compaction done.`	Exact text the model is asked to append at the end of the summary.

Append mode is the recommended default because it preserves OpenCode's built-in compaction behavior. Replace mode is available when the complete prompt needs to be controlled by this plugin.

When neither a prompt nor a memory file is available, the plugin asks the model to echo opencode-plugin-compaction-prompt: No custom compaction applied. instead.

Development

bun install
bun test
bun run typecheck
bun run build
bun run pack:check

The npm package exposes the compiled entrypoint at dist/index.js and TypeScript declarations at dist/index.d.ts.

Publishing

Update the changelog

Add the changes for the new version to CHANGELOG.md.

Verify the release

bun run format:check
bun test
bun run typecheck
bun run build
bun run pack:check

Publish the release

npm version minor -m "chore: release v%s"
git push origin main --follow-tags
VERSION="$(node -p "require('./package.json').version")"
gh release create "v$VERSION" --generate-notes
npm publish

Use npm version patch or npm version major when appropriate. npm publish rebuilds dist/ automatically.

Compatibility

The plugin uses OpenCode's experimental.session.compacting hook. OpenCode may change experimental plugin APIs between releases; test the package against the OpenCode version you support.