<p>We present a fully automated framework to compute production spin-density matrices for generic collider processes at tree level within M<span>a</span>dG<span>raph</span>5_<span>a</span>MC@NLO. The method assembles helicity amplitudes into event-by-event production matrices. These are written to the LHE file in a compact form, together with run metadata, enabling direct post-processing of quantum observables. The implementation supports bi- and multipartite qubit and qutrit final states, configurable reference frames, and both polarised and unpolarised initial states. A companion, easy-to-extend library provides analysis routines to determine key quantum-information measures and witnesses. These include purity, concurrence, and entanglement of formation for qubits; Peres-Horodecki tests and negativity; spin-polarisation vectors and correlation matrices; <i>D</i>-coefficients; and stabiliser-based “magic” measures. As a result, multi-particle quantum correlations can be quantified systematically. We validate the implementation against known results for <InlineEquation ID="IEq1"> <EquationSource Format="MATHML"><math display="inline"> <mi>t</mi> <mover accent="true"> <mi>t</mi> <mo stretchy="true">¯</mo> </mover> </math></EquationSource> <EquationSource Format="TEX">\( t\overline{t} \)</EquationSource> </InlineEquation> and <i>VV</i> (<i>V</i> = <i>W</i>^<i>±</i>, <i>Z</i>) production in <i>pp</i> and <i>e</i>⁺<i>e</i>⁻ collisions and in heavy-resonance decays. We then consider new applications and study quantum correlations in several LHC final states: <InlineEquation ID="IEq2"> <EquationSource Format="MATHML"><math display="inline"> <mi>t</mi> <mover accent="true"> <mi>t</mi> <mo stretchy="true">¯</mo> </mover> <msup> <mi>W</mi> <mo>±</mo> </msup> </math></EquationSource> <EquationSource Format="TEX">\( t\overline{t}{W}^{\pm } \)</EquationSource> </InlineEquation>, <i>tW</i>⁻ vs. <InlineEquation ID="IEq3"> <EquationSource Format="MATHML"><math display="inline"> <mi>t</mi> <mfenced close=")" open="("> <mrow> <mover accent="true"> <mi>t</mi> <mo stretchy="true">¯</mo> </mover> <mo>→</mo> <msup> <mi>W</mi> <mo>−</mo> </msup> <mover accent="true"> <mi>b</mi> <mo stretchy="true">¯</mo> </mover> </mrow> </mfenced> </math></EquationSource> <EquationSource Format="TEX">\( t\left(\overline{t}\to {W}^{-}\overline{b}\right) \)</EquationSource> </InlineEquation>, and <InlineEquation ID="IEq4"> <EquationSource Format="MATHML"><math display="inline"> <mi>t</mi> <mover accent="true"> <mi>t</mi> <mo stretchy="true">¯</mo> </mover> <mi>t</mi> </math></EquationSource> <EquationSource Format="TEX">\( t\overline{t}t \)</EquationSource> </InlineEquation> vs. <InlineEquation ID="IEq5"> <EquationSource Format="MATHML"><math display="inline"> <mi>t</mi> <mover accent="true"> <mi>t</mi> <mo stretchy="true">¯</mo> </mover> <mi>t</mi> <mover accent="true"> <mi>t</mi> <mo stretchy="true">¯</mo> </mover> </math></EquationSource> <EquationSource Format="TEX">\( t\overline{t}t\overline{t} \)</EquationSource> </InlineEquation>.</p>