Does my idea fit into the call?
First, read the call several times. Then do not panic.

If your idea (the red square) fits the call (blue square) as in figure 1 and 2 it is ok. In figure 2 you will have to argue that you are within the call covering a smaller part of the total but an important one. If your idea is outside the call you must redefine it. You must cut away all aspect of your idea that is not within the scope of the call.
However for the thematic calls as in Horizon 2020 you will build a partnership that shall answer to the call text together as a project.
In figure 4 the 6 partners cover the whole project/call. This is a good partnership. It also shows that even if you yourself only cover a smaller portion the consortium will cover the full call.
In figure 5 there is possible problem as the grey and red partner covers the same part of the call. Either the contribution of the two partners must be adjusted or the grey partner must be taken out. Two partners doing the same are not wanted. (If you have good reasons it may be ok e.g. if you need two to verify the same to strengthen the results. But then you must explain this clearly).
In Figure 5 there is also a possible problem that a relative big part of the proposal is not covered (upper right corner). A new partner should be added.
Figure 6 lacks central partners and two partners are partly outside the call. You need central partners. And the two partners partly outside the call must either be taken out or their work must be redefined. Such a project will not be funded.
Remember:
- You do not need to cover the full call alone
- You can argue that you have a good focused idea even if it is not covering the full call spot on. (But you must argue strongly for such a position)
©OUS-aro