Plugins

Cross-session messaging across one or all workspaces: session_list finds top-level sessions by recency or title, session_send_message steers or queues attributed messages (cold-resuming stored sessions when needed), session_create opens titled top-level sessions with an initial task, and a client renderer displays relayed messages as user-side chat bubbles naming the sender session.

Cross-session agent-to-agent messaging for DeepSeek Harness — address another session by name and deliver a message into its inbox.

Sessivra: drag sessions into resizable split views, insert native @ references into drafts, exchange linked replies and review delegated work before queued follow-ups. npm package dsh-plugin-sessivra.

Peer messaging between user-launched sessions in one workspace: discover peers, relay coordination messages, pause reception, and get advisory write-scope conflict warnings.

DSH plugin: cross-session call center for agents. session_message delivers messages between DSH sessions (idle: visible full-text wake; busy: mid-turn-safe notice; plus runtime-context notes) and resolves targets by registered contact name (stale-id-proof