New Minecraft snapshot has changed command syntax on give, so most commands will no longer work in the latest snapshot.
An update is in progress, snapshot can be selected from the dropdown menu in the top right corner of the page.
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Try the Commands Troubleshooting and Help page if you get stuff with server errors.
Minecraft Versions Permalinks
If you find yourself using a particular version all the time, you can link directly. There is some crossover between versions, so there will be quirks.
