@snow-the/dsh-session-handoff

Session handoff & context management for DeepSeek Harness — built because the existing session-management and context-pruning plugins were written before the latest DSH update and don't cover the full workflow.

Why

Long sessions (like a 170k-line r32 session) hit context limits, trigger repeated automatic compaction, and stall. Switching to a fresh session loses all progress. This plugin fixes both halves — and more:

1. Handoff — export a structured, portable handoff document so a fresh session can continue seamlessly.
2. Active context pruning — compress spent history before the context window fills (official compaction API, model-authored summaries).
3. Session management — trash / restore / purge / list sessions.
4. Model routes — every registered route (official API, Ark, custom, vision-toolkit wrappers) is orderable and switchable; each route can pin its own model and reasoning effort (provider:model:effort), or follow the chat's current selection. No model id is hard-coded.
5. ACP thresholds — tune compaction limits without touching YAML.

Tools

Module A — Handoff (zero dependencies)

Tool	Purpose
handoff_status	Compact session overview: turns, messages, tool usage, checkpoints, context pressure
handoff_export	Parse the session into a structured Markdown handoff under <workspace>/.dsh-handoff/ + a ready-to-run handoff package (OpenViking archive command, archify diagram command — only when those enhancers are present)
handoff_resume	Load the latest handoff document in a fresh session and continue

Also /handoff command.

Module B — Active Context Pruning (official compaction API)

Tool	Purpose
acp_status	Usage, surface seq map, limits (soft/hard pressure level)
acp_compress	Replace an inclusive surface seq range with your summary (ctx.compaction.compactRegion)
acp_decompress	Read the original text hidden by a checkpoint (read-only)
acp_search	Search visible + hidden compacted history
acp_config	Show the active thresholds (soft/hard limits, preserveRecent, minTokens, nudge)
acp_set_limit	Persist new thresholds into settings.yaml (new sessions take them)

Plus a system-prompt pressure banner that nudges the model to compress past the soft/hard limit (60% / 70% defaults), and a compaction.summarize interception so model-authored summaries are used.

Module C — Session management

Tool	Purpose
session_list	List sessions (optionally including the trash)
session_trash	Archive + move a session's artifact into the plugin trash (recoverable; refuses running sessions)
session_restore	Move it back and unarchive
session_purge	Permanently delete artifact + trash entry

Trash entries persist as JSON under $DSH_HOME/dsh-session-handoff-trash/ (keeps the newest 10; oldest overflow auto-purged).

Module D — Model routes (same model, many vendors)

Tool	Purpose
model_routes	List every route serving deepseek-v4-flash: provider, baseURL, key env + family (ark-/sk-), default marker (incl. vision-toolkit- variants), vision wrapper variant
model_switch	Point agent-default-model at a route (persisted to settings.yaml; new sessions use it). Optional vision:true selects the vision wrapper variant; warns when the key family is missing

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