Yes, tool is playable
...and is worth 5 points.
Found in the following dictionaries
Enable (Words with friends)
SOWPODS (Collins Scrabble Words)
OTCWL2014 (NASPA Word List 2014)
TWL06 (NASPA List 2006)
"Tool" Definition
noun
A design impressed on a book cover by such a stamp.
A device, such as a saw, used to perform or facilitate manual or mechanical work.
A machine, such as a lathe, used to cut and shape machine parts or other objects.
A person used to carry out the designs of another; a dupe.
Computer Science An application program, often one that creates, manipulates, modifies, or analyzes other programs.
phrasal-verb
Tool up To provide an industry or a factory with machinery and tools suitable for a particular job.
verb
To cause (a vehicle) to go .
To shape, form, or finish with a tool.
To letter or ornament (as leather or gold) by means of hand .
To equip (as a plant or industry) with tools, machines, and instruments for production.
verb-transitive
Slang To drive (a vehicle): tooled the car at 80 miles an hour.
To form, work, or decorate with a tool.
verb-intransitive
Slang To drive or ride in a vehicle: tooled up and down the roads.
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