In DeepSeek Harness, session data is typically bound to a specific workspace directory. To restore the complete conversation history, subagent sessions, and associated attachments on another device, manually copying files is error-prone and hard to maintain. Below is dsh-session-migrator, a plugin that provides a visualized workflow and supports importing ZIP, JSONL, or folders by drag-and-drop to enable cross-device session migration.

Core Features

This plugin provides the following capabilities:

  1. Visual workflow: Complete the import through sidebar actions, with no need to memorize commands.
  2. Drag-and-drop import: Supports dragging a Harness session ZIP, session.jsonl, or a complete export folder into the page.
  3. Cross-device workspace mapping: Automatically rewrites the cwd field of imported sessions to match the directory structure on the target device.
  4. Full session tree: Imports the root session and all descendant sessions under subagents/<id>/session.jsonl.
  5. Safe duplicate import: If a session with the same name already exists in the target workspace, the plugin clones the entire import tree, generates new UUIDs, and remaps lineage, never overwriting existing data.
  6. Attachment migration: Restores referenced PNG, JPEG, WebP, and GIF attachments and validates their content-addressed IDs.
  7. Harness-native validation: Decodes storage lines with decodeStorageRecord() and validates reconstructed logs through Session.create(), ensuring that data written to Harness is correctly formatted.
  8. Instant original titles: Warms up the Harness projection cache during import so that the workspace list displays session titles before the sessions are opened.
  9. Multilingual support: The UI automatically follows the current Harness language (English and Chinese are supported).
  10. CLI fallback: Retains the /session-import command for scripted or local workflow needs.

Installation and Enablement

Run the following steps on the machine running DeepSeek Harness:

git clone https://github.com/Suixin04/dsh-session-migrator.git
cd dsh-session-migrator
npm install
npm run build:client

Install into the Web configuration file:

dsh plugin --profile web add /absolute/path/to/dsh-session-migrator

After installation, restart the existing dsh web process. An Import sessions action button appears at the bottom of the sidebar.

Typical Usage

Visual Import

  1. Click Import sessions in the sidebar.
  2. Choose a ZIP/JSONL file, a complete export folder, or drag the files directly onto the Harness page.
  3. Select the target workspace card or drag the files onto it.
  4. Wait for validation and persistence to complete.
  5. Click Open imported session.

Command-Line Import

Use the workspace of the current session:

/session-import "/absolute/path/dsh-session-xxx.zip"

Specify another existing workspace:

/session-import "/absolute/path/dsh-session-xxx.zip" --workspace "/absolute/path/to/project"

Unpacked export directories or a single JSONL file are supported:

/session-import "/path/to/unpacked-export" --workspace "/path/to/project"
/session-import "/path/to/session.jsonl" --workspace "/path/to/project"

Use Cases and Notes

Use cases:
- Migrate full DeepSeek Harness session history between different physical devices.
- Back up session data and restore it to a new environment.
- Create a session copy in the target workspace that matches the source environment structure while preserving lineage.

Notes:
- Version requirement: The DeepSeek Harness version must be 0.1.1-rc.2 or a compatible build.
- Directory requirement: The target workspace directory must already exist on the target host.
- File scope: Session exports do not include project files (such as Git repository files); migrate the project separately with Git or another synchronization method.
- Sensitive data: Session exports may include complete prompts, responses, system context, tool calls, absolute paths, and images. Treat them as sensitive data.
- Limit checks: The plugin enforces archive, JSONL, and entry-count limits; it rejects unsafe paths, duplicate entries, malformed logs, duplicate IDs, and circular lineage.
- Persistence mechanism: Harness persistence is append-only. If the plugin fails during writing, a successfully committed prefix may remain. Importing again after a partial write creates an entirely new cloned tree.
- Migration scope: This plugin migrates only session state and referenced images; it does not migrate repository files, credentials, model provider settings, or external service configurations.

Plugin directory: SkillHub
Source repository: GitHub