It would be useful if we could link to the minecraft wiki using server commands.

Examples:

"wiki trading?"   link to minecraft.gamepedia.com/Trading
"wiki bow?"       link to minecraft.gamepedia.com/Bow
"wiki spawn?"     link to minecraft.gamepedia.com/Spawn
"wiki tutorials"  link to minecraft.gamepedia.com/Tutorials

It gets a little more complicated for the tutorial pages

"wiki tutorial village mechanics" link to "http://minecraft.gamepedia.com/Tutorials/Village_mechanics"

No idea if this is practical to implement, but it's an idea I thought that I would mention.

what about just asking to other players/watching a tutorial?

Wouldn't be a fan of spam in getting chat with this when someone can just easily type that query into Google and one click later reach the page.
The false positives would also be significant given the amount of key words.

also its a wiki, people can edit it

I am a wiki editor :P I edited it once for one of the snapshot features

I edited some articles in wookiepedia