Retrieve the current list of valid item categories for your state via the item categories endpoint; there is no endpoint to create new categories, since they are state-controlled reference data.
Retrieve valid units of measure from the units-of-measure reference endpoint.
Create any needed strain or brand records first if your item will reference one.
Submit the item (name, an exact category string from the categories endpoint, unit of measure, and strain/brand if applicable) to the item create endpoint.
Update an existing item using the item update endpoint, noting the endpoint structure differs between API v1 and v2.
Confirm the item appears in the active items listing.
Known gotchas
You cannot create custom item categories through the API; always re-fetch the categories list rather than hardcoding values, since state-controlled category lists change periodically.
API v1 splits item create and update into two separate endpoints, while v2 uses the same base path with a different HTTP method.
Some states may require manual review or approval of newly created items in the Metrc UI even after a successful API submission; confirm your state's process.
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