This is not a valid Fuel installation so Oil is a bit lost.

FuelPHPはエラーメッセージが不親切
oilコマンドを叩いたらこのようなエラーメッセージが出て動きませんでした

~~~
$ oil –help
This is not a valid Fuel installation so Oil is a bit lost.
http://fuelphp.com/docs/installation/instructions.html
~~~

Instruction – Installation – FuelPHP Documentationにあるとおりにコマンドを実行した場合

~~~
$ curl get.fuelphp.com/oil | sh
$ oil create blog
~~~

blogディレクトリ配下はこうなります

~~~
drwxr-xr-x 14 user 476 7 16 10:21 .
drwxr-xr-x 4 user 136 7 16 11:05 ..
drwxr-xr-x 13 user 442 7 16 10:21 .git
-rw-r–r– 1 user 168 7 16 10:21 .gitignore
-rw-r–r– 1 user 643 7 16 10:21 .gitmodules
-rw-r–r– 1 user 24190 7 16 10:21 CHANGELOG.md
-rw-r–r– 1 user 6519 7 16 10:21 CONTRIBUTING.md
-rw-r–r– 1 user 1817 7 16 10:21 README.md
-rw-r–r– 1 user 3243 7 16 10:21 TESTING.md
-rwxr-xr-x 1 user 2318 7 16 10:21 build.xml
drwxr-xr-x 17 user 578 7 16 10:21 docs
drwxr-xr-x 7 user 238 7 16 10:21 fuel
-rwxr-xr-x 1 user 1188 7 16 10:21 oil
drwxr-xr-x 5 user 170 7 16 10:21 public
~~~

ここにoilコマンドを実行するファイルがあるので、移動して実行しましょう

~~~
$ cd blog/
$ oil –help

Runtime options:
-f, [–force] # Overwrite files that already exist
-s, [–skip] # Skip files that already exist
-q, [–quiet] # Supress status output
-t, [–speak] # Speak errors in a robot voice

Description:
The ‘oil’ command can be used in several ways to facilitate quick development, help with
testing your application and for running Tasks.

Environment:
If you want to specify a specific environment oil has to run in, overload the environment
variable on the commandline: FUEL_ENV=staging php oil commands

Documentation:
http://docs.fuelphp.com/packages/oil/intro.html
~~~

パスを通しておくか、コマンドは常にここで叩くかしないとダメっていうそれだけの落ちでした