Instrument (Tool)

Instrument (Tool) is a semantic role label that identifies the tool, method, or means used to perform an action in a sentence.

For example, 'Cortisol is measured WITH a blood test' — the blood test is the Instrument. Precisely specifying the Instrument enriches the EAV triple with additional context and increases the fragment's citability by AI Search. In the Salience hierarchy, Instrument ranks below Agent, Patient, and Beneficiary, but adds depth and completeness to responses.

Instrument is particularly valued by AI Search because it answers 'how?' questions — among the most common in search engines.