DeepSeek Harness v0.1.6-alpha.2: Plugins, Sidebar & Sub-agents

Author
DeepSeekAgent.io Editorial Team
Published
Updated

DeepSeek released dsh-v0.1.6-alpha.2 on September 17, 2026. It extends the alpha.1 terminal, Headless, remote-workspace, and experimental surfaces with first-class plugin management, file review, Office previews, browser views, and Sub-agent conversations inside the sidebar.

The visible theme is a broader workspace inside DSH. The deeper compatibility changes affect runtime dependency resolution, plugin unloading, persistent Creator-mode installations, and continuable Sub-agent chains.

Release status

CheckStatus on September 20, 2026
GitHub Releasev0.1.6-alpha.2, Pre-release
GitHub tagdsh-v0.1.6-alpha.2
Commitddefc45
Previous releasev0.1.6-alpha.1

Pin the exact build when testing:

npx @deepseek-ai/[email protected] web

Reproducible experiments and shared Profiles should use the full version instead of allowing the alpha channel to move underneath plugin and Session tests.

Plugin management enters the main interface

The new Plugins page can install plugins, edit configuration, and enable or disable plugins live. The manager and its Agent-facing tool are part of the DSH Base Composition shared by Web, Headless, SDK, and ACP profiles.

The management surface exposes six operations:

OperationPurpose
list_pluginsList plugin entries in the current Profile
list_bundlesList installed Bundles
set_pluginEnable or disable one plugin
set_bundleEnable or disable a Bundle
install_bundleInstall a new Bundle
remove_bundleRemove an installed Bundle

Mutations persist across Sessions in the Profile, so every operation requires danger-full-access or explicit approval. Packages with build scripts require approval for the named scripts. Live profiles apply changes immediately; startup profiles may require a restart.

The sidebar becomes a unified work surface

Alpha.2 brings several outputs into the same sidebar:

  • end-of-turn file-change cards with file-by-file diff review;
  • Word, Excel, and PowerPoint previews;
  • a browser view for a specified URL;
  • Sub-agent conversations and their delegated context;
  • submitted-plan previews;
  • persisted sidebar layouts and terminal connections across refreshes.

Files, pages, plans, and child Sessions can now be inspected without leaving the parent conversation. That supports a practical pattern: the main Agent presents the result while the sidebar exposes the material needed to verify it.

File and workspace experience

Workspaces can be grouped by directory hierarchy. Existing files open directly, and file previews and terminals are available before the first message. Trajectory renders text, image, and file attachments consistently, including thumbnails.

Composer menus now share keyboard behavior: arrow keys select, Enter or Tab confirms, and Escape closes. Context usage moves to the composer footer with details on click, and CLI and Web startup waits are shorter.

Vision fix and model-catalog cleanup

Alpha.2 fixes pi-ai vision models being classified as text-only and lets users adjust input types manually. After upgrading, create a new Session, inspect the selected model's input types, and run an image test that depends on random text, color, and spatial relationships.

The default list also removes V4 Flash and V4 Flash Vision Exp. New configurations should use the current model ID so legacy aliases and local capability declarations do not keep producing ambiguous attachment behavior.

New bounds for continuable Sub-agents

Continuable chains now default to at most eight live children and a delegation depth of one, both configurable in settings. These values control how many child Sessions remain live and how many layers of delegation can form.

They do not cap each child's turns, context growth, or provider spend. Cost analysis still needs the parent Session, every child Session, concurrency periods, and the provider invoice.

What plugin developers need to inspect

Runtime resolution and unloading

Plugin dependencies now resolve at runtime and Plugin Manager can unload them. A plugin can no longer assume that process exit is its cleanup path. Verify that:

  • timers, watchers, and network connections stop on unload;
  • tools, commands, routes, and event listeners unregister;
  • re-enabling does not mount duplicate handlers;
  • partial activation failures leave a diagnosable state;
  • shared services have clear ownership across Sessions.

Creator mode

Creator mode removes the previous Cordis dynamic-definition and execution tools. It now installs persistent plugins through Plugin Manager. Generated capabilities therefore become Bundles that remain in a Profile, making manifests, defaults, build-script approval, and uninstall behavior part of the deliverable.

Multiple Client Session instances

Client Sessions can coexist, with related API and slot changes. Plugins that treated the current client as a global singleton should test state isolation, event ownership, and shutdown ordering.

Fixes and diagnostics

Alpha.2 also fixes:

  • Messages API endpoint construction and malformed historical tool inputs;
  • pending Inbox restoration after restart;
  • repeated approval for an already active permission mode;
  • flashing console windows for PTC and Shell on Windows;
  • unclear handling when another DSH instance owns a Session;
  • resize handles covering content and nested tooltip overlap.

Startup failures are grouped by failed and pending services, with full diagnostics saved to a log. When an upgraded Profile fails, identify the service group first and then inspect runtime-resolution and unload compatibility.

Upgrade checklist

ScenarioValidate after upgrading
Web usePlugins page, file review, Office previews, sidebar restore
Vision modelsinput types, effective model ID, image content blocks
Sub-agent workfloweight live children, depth one, child usage
Plugin developmentload, unload, re-enable, failure recovery
Creator modeBundle install, persistent config, build approvals
Multiple clientsSession isolation, API and slot compatibility

Alpha.2 remains a Pre-release. Back up Profiles and Sessions, then validate startup, model requests, images, file previews, plugin toggles, Sub-agents, and restart recovery in a copied environment.

Related reading

FAQ

Is v0.1.6-alpha.2 stable?

No. GitHub marks it as a Pre-release; pin the exact version for testing.

Does disabling a plugin stop it immediately?

Live profiles support runtime toggles and unloading. The plugin must still release its resources correctly, and some startup-profile changes require a restart.

Do the Sub-agent defaults prevent token overspend?

They bound live-child count and delegation depth. They do not replace turn budgets, context monitoring, or invoice reconciliation.