MUSHclient has an inbuilt spell checker (supplied as a separate DLL file).

You can use this in various ways:

• Spell check each command automatically before it is sent
  
  
• Spell check commands on request (by keystroke or menu option)
  
  
• Spell check arbitrary text from scripting
  
  
• Spell check the command window on request from scripting
  

See Also ...

Command

(SpellCheck) Spell checks the command in the command window

Dialogs

New Spell-Check Dictionary
Spell Check

Functions

(AddSpellCheckWord) Adds a word to the user spell check dictionary
(SpellCheck) Spell checks an arbitrary string of text
(SpellCheckCommand) Spell checks the text in the command window
(SpellCheckDlg) Spell checks an arbitrary string of text, invloking the spell-checker dialog

(Help topic: general=spellcheck)