I wrote this sentence
Using the fields on the left-hand side, the user can specify the required values for the context variable.
Suppose you want to cook something, the recipe specifies a certain temperature. Then you say I heated the pot to the ..... value
In my example, in order that the user achieve his goal, he should provide certain values for the context variables.
I think of perquisite
In the context of a recipe specifically, just about every recipe I've ever seen written in English supplies the temperature value without any antecedent or substitution in the sentence ("Set the temperature to 450 degrees" rather than "Set the temperature to the required value"). "The required" or "prerequisite" offers a formal or technical tone that would look strange on a recipe or any other informal set of instructions.
You can use "the correct" or "the proper" ("Set it to the correct temperature") if you know that the reader knows which temperature you are talking about. If you wish to refer to something that you have already mentioned before on a written page, you can use "the above" (or "the below"/"the following" if you haven't mentioned it yet). Ex. "Set the temperature to the above value."
Often, in English, there is not any need for an adjective that describes the temperature we want because "the" is a definite article. As long as there is only one "thing" that we are talking about, "the" can be used to indicate it with no ambiguity. For instance, if you are writing a recipe for baking cookies, then the cookies are only going to be baked at one temperature (most likely) the whole time. Therefore, if you listed the baking temperature at the beginning of the recipe, you could say "Now, set your oven to the temperature," and the reader would know what you are talking about.
