DeepSeek Harness v0.2.1-alpha.2

DeepSeek Harness v0.2.1-alpha.2: Models, Sessions & Plugins

Author: DeepSeekAgent.io Editorial Team
Published: Oct 10, 2026
Updated: Oct 10, 2026

DeepSeek Harness v0.2.1-alpha.2 reached npm on October 9, 2026. The alpha tag now resolves to this build, while latest and next remain on 0.2.0-rc.2. An ordinary unpinned installation therefore does not move to alpha.2; users receive it only by selecting the alpha channel or the complete version.

At the time of review, GitHub Releases did not contain a dedicated alpha.2 release note. This article is based on the npm publication and the official dsh-v0.2.1-alpha.1...dsh-v0.2.1-alpha.2 source comparison. It does not present source-level findings as an unpublished official announcement.

Major changes

Area	User-visible change
DeepSeek models	Correct V4.1 Flash's display name and hide unconfigured or unavailable choices
Session migration	Surface format status and guide migration-required forks and subagent discovery
Plugin settings	Reorganize settings and add an experimental-feature catalog
Plan Mode	Exit only after approval; dismissing review ends the current turn
Conversation UI	Improve long-content folding, scroll following, and layout restoration
Personalization	Configure text, code, and terminal fonts and sizes independently
Voice input	Select a microphone, inspect input levels, and handle device hot-plugging
Model calls	Keep request-extension failures from blocking the entire request

V4.1 Flash naming and model selection

alpha.2 corrects the display name of DeepSeek V4.1 Flash. Earlier interfaces could show a name such as DeepSeek-V41-Flash, whose missing decimal point made it look like a separate model ID. The fix changes the label; the underlying model ID continues to come from the Provider configuration.

The model interface also hides unconfigured DeepSeek models and unavailable saved selections. Catalog entries that the active account or Provider cannot use no longer compete visually with working choices. If a former selection disappears after upgrading, inspect the Provider, credential, and model ID before concluding that the model itself was removed.

Session migration becomes a visible workflow

DSH session formats evolve with the runtime. alpha.2 exposes format status in the session header and gives the frontend a guided path for migration-required forks. When subagents are involved, the interface also helps locate related sessions.

This is not a promise that every old session becomes automatically compatible. Back up ~/.dsh and retain exports or delivered work before upgrading. When migration is requested, create the compatible fork first, then verify the parent session, child sessions, and attachments.

Plugin settings and the experimental catalog

The Plugins interface is reorganized and gains an experimental catalog. Stable plugins, optional bundles, and experimental capabilities are easier to distinguish, while Auto review continues to carry an experimental marker.

For users, this reduces the effort of finding a capability. Plugin authors still need to test more than the installed state:

dependencies after enabling a Bundle;
cleanup of tools, menus, and resources after disable or uninstall;
build-script approval requirements;
reliance on profile-patch behavior changed or reverted during the alpha cycle.

alpha.2 also records ignored dependency build scripts reported by non-interactive pnpm runs, allowing Plugin Manager to expose the approval path. It does not approve third-party scripts automatically; users still need to inspect the package and its install behavior.

Clearer Plan Mode exit semantics

Two interaction fixes remove ambiguity:

Plan Mode exits through its guidance only after the user approves the plan.
Dismissing or abandoning plan review ends the current turn instead of treating the plan as approved.

This matters for deletion, publishing, payment, and broad scope changes. Closing a review surface is not authorization, and the Agent should not continue the proposed work merely because the dialog disappeared.

Conversation layout, fonts, and voice input

The conversation interface reworks folded-content height, scroll following, and viewport layout. Collapsing long tool or reasoning content should no longer leave pathological empty space, and changing modes or returning to a running Session triggers a layout reset.

Display settings can configure text, code, and terminal fonts and sizes independently. Body copy, code reading, and terminal density no longer have to share one global compromise.

Voice input adds microphone selection and input levels and improves state across device hot-plugging. Operating-system and browser permissions still apply: appearing in the selector does not itself grant recording access.

Request-extension failures no longer sink the model call

DSH extensions can modify parameters or context while a model request is prepared. In the earlier path, a failing request extension could block the entire call. alpha.2 records and attributes the failure while allowing the model request to continue, and repeated failures are logged without flooding the interface.

The fallback improves availability but does not make every extension optional. If an extension enforces security, permission policy, or essential context, its failure remains an operational problem that should be fixed rather than accepted as a permanent degraded mode.

Should you upgrade?

Most users should remain on npm latest, currently 0.2.0-rc.2. alpha.2 is appropriate when you are:

testing V4.1 Flash catalog and display behavior;
validating migration and subagent discovery for older Sessions;
developing DSH Plugins, Bundles, or experimental features;
evaluating the new font, voice-input, or folding experience;
prepared for interface and behavior changes on the alpha channel.

Pin the complete version while testing:

npx @deepseek-ai/[email protected] web

Back up Profiles, Sessions, and plugin configuration, then verify models, Plan Mode, plugin transitions, and old sessions in an isolated workspace. Do not make the alpha channel a team's only daily environment.