The phrase "a primary tool to" is correct and usable in written English.
It can be used when describing a main method or resource for achieving a specific goal or purpose.
Example: "The new software serves as a primary tool to enhance productivity in the workplace."
Alternatives: "a key resource for" or "a main method to".
Confocal Raman spectroscopy has been a primary tool to characterise 2-D materials.
In general, computer architects use simulation as a primary tool to evaluate the computer's performance.
This paper presents a global conceptual river ice model that can be used as a primary tool to predict ice cover types and to identify ice processes potentially affecting cold region channels.
An adjoint Monte Carlo code, NOVICE, which was developed specifically for space radiation transport problems, was used as a primary tool to study an optimum shielding design for a Jupiter mission.
It has been a primary tool to terrorize both populations in areas they have captured and to gain international coverage, attention and ransom.
A primary tool to fight miasma was hygiene, a term that echoes down in the name of our Society.
Soon after it sought court protection, United said a low-fare airline would be its primary tool to win back passengers.
A primary tool employed to determine the oxidation of lubricants is differential scanning calorimetry (DSC) or pressurized differential scanning calorimetry (PDSC), where the oxygen concentration is adjusted to exceed that at ambient pressure to expedite the oxidation process.
A primary tool used to identify the LSMA sites on the satellite imagery was an on-screen digitizing technique based on the physiognomic attributes of objects and their spatial relationships or associations (Campbell 2006).
[Author's response: The compensatory base change has been a primary tool used to infer probable RNA secondary structure.
