# Undefined index: Controller

#1

SS4.3

I’m trying to add Routes to a routes.yml file, and every time I run dev/build I get the following error:

`[Notice] Undefined index: Controller`

`### GET /dev/build?devbuildtoken=94af26bf9c50106ca7122b533a035c77&amp;flush=&amp;flushtoken=1f016c2e2210ddce5a1bbec207ea1b94`

`Line **439** in C:\projects\true\tmtoolkit\tmtoolkit\vendor\silverstripe\graphql\src\Controller.php**`

My routes.yml code is as follows:
`---`
`Name: approutes`
`After:`
`- '#rootroutes'`
`- '#coreroutes'`
`---`
`SilverStripe\Control\Director:`
`rules:`
`- 'region//\$Action/\$ID': 'RegionController'`

If I take out the last line I don’t get an error

#2

It’s OK, I had a ‘-’ at the start of the last line, which apparently shouldn’t be there for routes.
The error message was a bit cryptic though