+* `PDG="<211,-211>"`: The particle IDs to apply this smearing to.
+* `Type="[Fractional|Absolute|Function]"`: The type of smearer to use. `Fractional` and `Absolute` use a Gaussian smearer. For `Fractional` the Gaussian width is set to `<WidthAttribute>*ParticleKinematicPropertyValue` and for Absolute it is simple `<WidthAttribute>`.
+* `Kinematics="[KE|Momentum|TEVis|KEVis|Theta|CosTheta]"`: The particle kinematics to smear. For the majority of practical uses, where an accepter is also in use, `TEVis` and `KEVis` produce the same results. As only a single property smearer can be used per PDG, the use of `Theta` and `CosTheta` are of very limited use.
+
+Additional attributes that depend on the value of the `Type` attribute are as follows:
+* `Width="<value>"`: The width of the Gaussian used for `Fractional` or `Absolute` type smearers.
+* `Function="<TMath::Gaus(x - {V},0,0.2*{V})>"`: The function to throw the smeared values from for `Function` type smearers. The example function here should give the same result as `<Smear Type="Fractional" Width="0.2" />`.
+* `P[1|2|3|...]="<value>"`: Extra parameters to replace in the `Function` attribute value. *e.g.*: `<Smear Function="{V} + TMath::Gaus(x - {V},0,{P1}*{V})" P1="0.2" />`. Mostly just for clarity. An element can contain any number of numbered parameters, but they must be numbered in increasing order.
### TrackedMomentumMatrixSmearer
-Documentation to follow. Sorry.
+Applies momentum or kinetic energy smearing to tracked particles.
+* `PDG="<211,-211>"`: The particle IDs to apply this smearing to.
+* `InputFile="<ROOT file location>"`: The root file that contains the input smearing matrix.
+* `HistName="<TH1D name>"`: The name of the histogram within in the input root file. Can be located within a subdirectory of the TFile.
+* `Kinematics="[KE|TE|Momentum]"`: The kinematics to smear.
+* `MatrixToInternal="<value>"`: The scale factor used to scale the units used in the smearing matrix to MeV.
+* YIsTrue="[1|0]": Whether the Y or X axis of the input histogram denotes the true kinematic property axis.
+
+The `<TrackedMomentummatrixSmearer>` element can also contain any number of `<Smear>` element, which are used for PDG codes that do not have a `<SmearMatrix>` element. Their behavior is as in `<GaussianSmearer>`. As this smearer can only smear tracked particles, using `<Smear>` elements to add visible energy smearing is the expected use case.