I want to expose my F# libraries as a scriptable tool for data manipulation.
Optimally, I want this scripting facility to not require a full F# install with fsi and so on.
Is there a way to link into the FSI libraries to execute scripts from F# code? My google-fu is failing me on this one, and the F# sources for fsi are a bit tangled.
No, there's no hosting API for F# interactive sessions. fsi.exe itself is factored into a lightweight client process that handles the interaction, and a background server process that does the heavy lifting. (The server process is built atop the F# compiler DLLs, which is why you need a full install of F#, and not just the F# runtime redist. BTW, exposing an API for this is a somewhat common request and something the F# team will consider for a future release.)
That said, if clients do have a full install of F#, then you can always just ship some scripts (.fsx files) clients can #load, or libraries (.dll files) that clients can #r to start off their interactive fsi sessions. This is definitely a good mode for using F# interactive for data manipulation and exploration.