SCP Foundation

The main idea is that MTF-Tau-8 works to secure and contain anomalies reported by/through the Department of Temporal Anomalies (DoTA) while keeping with the Novikov self-consistency principle¹.
MTF-Tau-8 requires three (3) things:

1. It enlists personnel who are both sensitive and susceptible to the deterministic machinations of the universe.
2. It has full access to the discovery logs of all relevant SCPs, so as to replicate the circumstances of discovery when necessary (and thus maintain causality).
3. It operates in secret. Only the O5 Council, the Ethics Committee, the Department of Temporal Anomalies, and research personnel for specific scips know of its existence. Even they know only of its existence; its action reports are released post-hoc².

MTF-Tau-8 is directed through a "time messenger" machine called the Coordinator³. As they stand, both MTF-Tau-8 and the Coordinator would serve solely as plot devices in my first SCP "The Reception." For the sake of my current project and future projects, I want to know if this is original, interesting, and/or reasonable enough to implement.

Thanks in advance.

You have this a little backwards. One does not set out to create an MTF - rather, one writes articles, referencing that MTF, at least obliquely, and once it has popular support, only then that MTF can stand on its own.

Write SCPs or tales about the kinds of problems this MTF would solve - one-off MTFs are fine in this case, and this is generally how most MTFs start. Once it starts getting referenced, other authors may start getting ideas about it, and write their own articles about it.

You can't just write an MTF from nothing - it must be established elsewhere first.