dsh-spell-check

A DeepSeek Harness plugin that spell-checks the composer the way Chrome does — the word you are typing is checked as you type it, and fixing it never takes your hands off the keyboard.

View on GitHub

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Install

dsh plugin --profile web add dsh-spell-check

Restart dsh. The checker is on from then on — no chip, no toggle, nothing added to the composer bar.

In the desktop app: Plugins → Add plugin, paste https://github.com/adithyanraj03/dsh-spell-check, install.

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What it does

Type, then press Tab

The word under the caret is checked as you type. When it is wrong, a strip appears directly above it:

Misspelled words carry a blue wavy underline - the plugin’s own marking, with Chromium’s red squiggles switched off:

Tab replaces the word and leaves the caret after it, so a second Tab corrects the next word rather than repeating the last. Escape dismisses, the arrows move between alternatives, 1–9 jump to one, and clicking an entry works too.

Right-click any word

The full ranked list, on the word you pointed at:

The menu opens only for a misspelled word that has suggestions. Everywhere else the normal menu still appears, so Cut/Copy/Paste are never taken away.

What it leaves alone

• Real words. hoe is not corrected to how, form is not corrected to from. That rule is what separates this from the autocorrect people switch off.
• Acronyms, ALL_CAPS, and anything with digits.
• Code. Silence inside a fenced block in the draft.
• @mentions and /commands.

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Local by construction

20,000 frequency-ranked English words plus ~730 curated misspellings, matched with Damerau-Levenshtein so atuo → auto, theh → the and recieve → receive each count as a single edit rather than two.

No network calls, no telemetry, no model. The dictionary ships inside the bundle — scripts/build-client.mjs splices src/engine.js and the word list into the client half, so the matching rules exist once and a keystroke costs nothing.

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Two things this composer taught us

• It is Lexical, and typing does not emit an input event — Lexical calls preventDefault() on beforeinput. The plugin listens to selectionchange, beforeinput and keyup; a listener on input alone is silently deaf.
• execCommand cannot be trusted to replace text. Edits are applied against Lexical’s own selection, not the DOM range the page supplies, so an insertText aimed at one word lands at the start of the draft. Replacements go through conversation.input.for(scope).setDraft(text).

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Requirements

dsh	status
0.2.1-rc.3	tested — strip, Tab, right-click menu, learned words
0.2.0	expected to work; the client half needs only slots, conversation, sessions

• Node 22+

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Licensed MIT. Issues and pull requests at github.com/adithyanraj03/dsh-spell-check.