dsh-composer-expand

Composer expand toggle for DeepSeek Harness (dsh). A ⬆/⬇ button in the composer tool row toggles the input between the default capped height and a tall 70vh writing view, so long drafts no longer scroll inside a tiny window.

Why

The harness caps the composer textarea at a small height by default (the seat sets --dsh-composer-text-max-height: 336px, which caps the textarea scrollport). When the draft grows long, you end up scrolling inside a few lines instead of seeing the whole draft. This plugin keeps the default behavior for short drafts and offers a one-click toggle for the times when you are writing a long prompt.

Features

• ⬆ button in the composer tool row — sits in conversation.input.right, the official seat for clickable controls beside the send button.
• Grows composer to 70vh on expand — flips a CSS class on the conversation scrollport; the composer card + textarea both relax their max-height. Click again to restore the default capped height.
• Persists per browser — the toggle writes localStorage[dsh-composer-expand:expanded] so the choice survives reloads and workspace switches.
• i18n zh/en — button label and tooltip follow the harness locale service.
• No custom wire protocol — pure client-side CSS toggle; no host command, no LLM call, no session log entry.
• Localize-safe — anchors the CSS on DSH's stable data-conversation-scroll / data-conversation-composer-overlay data attributes, not on hashed classnames that change per build.

Install

Prerequisites

The dsh CLI must be on your PATH. If you only ever ran the harness through npx, dsh is not installed and you will get zsh: command not found: dsh — install it globally first:

npm install -g @deepseek-ai/dsh

Add the bundle

For local development (this repo):

# 1. build the bundles (tsdown produces lib/index.js + lib/client.js)
pnpm install
pnpm build

# 2. add the bundle to your web profile
dsh plugin --profile web add ./

# 3. restart the harness with that profile
dsh --profile web

After the restart the ⬆ button appears in the composer tool row, next to the send button. Verify under Settings → Plugins that dsh-composer-expand is listed.

How it works

Piece	Mechanism
Button seat	conversation.input.right list slot (session scope); ctx.slots.inject registers a single React component
Toggle state	local React useState seeded from localStorage[dsh-composer-expand:expanded]; effect mirrors it back to localStorage on change
DOM hook	document.querySelector('[data-conversation-scroll]').classList.toggle('dsh-composer-expand-on', on) — the official stable attribute on the conversation scrollport
CSS contract	the .dsh-composer-expand-on class overrides --dsh-composer-text-max-height on [data-composer-seat] (the real 336px cap) to var(--dsh-composer-expand-height) (default 70vh) and gives [data-input-mirror] a min-height: 120px so the box visibly grows even with little content
Hard deps	export const inject = ['slots', 'locale'] — both are official harness client services
No host commands	lib/index.js is a no-op apply(); the whole plugin is client-side

Build

pnpm install
pnpm build   # tsdown: lib/index.js (ESM host) + lib/client.js (ModuleLoader client bundle)

Known limitations

• The toggle is per browser, not per session. DSH renders only one composer at a time, so the mismatch is invisible today; if a future release ever renders more than one, narrow the DOM selector.
• The expanded height is fixed at 70vh. A future version could expose a height slider in a settings card.
• The 336px cap (--dsh-composer-text-max-height) is a DSH design choice. This plugin only relaxes the composer textarea container, not the disclosure rows themselves.

License

MIT