diff --git a/schemas/beam.schema.json b/schemas/beam.schema.json
new file mode 100644
index 0000000..5dc0180
--- /dev/null
+++ b/schemas/beam.schema.json
@@ -0,0 +1,104 @@
+{
+    "$id": "https://www.istp-cnr.it/gray/schemas/beam",
+    "$schema": "https://json-schema.org/draft/2020-12/schema",
+    "title": "Gaussian beam",
+    "description": "Gaussian beam characterization at the launch point.",
+    "type": "object",
+    "properties": {
+        "cocos": {"$ref": "cocos"},
+        "power": {
+            "description": "Beam power at launch. Units [MW]",
+            "type": "number",
+            "minimum": 0
+        },
+        "freq": {
+            "description": "Wave frequency. Units [GHz]",
+            "type": "number",
+            "exclusiveMinimum": 0
+        },
+        "polarization": {
+            "description": "Beam polarization.\\nIt can be one of the plasma modes, or an arbitrary polarization,\\ncharacterized via the polarization ellipse parameters, that in general\\nwill couple to both OM and XM",
+            "type": "object",
+            "properties": {
+                "mode": {
+                    "description": "The propagation mode the beam couples to. One of:\\n  - `OM`: Ordinary mode\\n  - `XM`: eXtraordinary mode\n  - `ANY`: arbitrary polarization",
+                    "enum": ["OM", "XM", "ANY"]
+                },
+                "ellipse": {"$ref": "#/$defs/polEllipse"}
+            }
+        },
+        "pos": {
+            "description": "Point where the beam is defined",
+            "$ref": "coordscyl"
+        },
+        "dir": {
+            "description": "Beam direction at launch",
+            "type": "object",
+            "properties": {
+                "cocos": {"$ref": "cocos"},
+                "alpha": {
+                    "description": "Poloidal angle. alpha = atan2(-k_z, -k_R), with k the unit wavevector at launch. Units [deg]",
+                    "type": "number"
+                },
+                "beta": {
+                    "description": "Toroidal angle. beta = asin(k_phi), with k the unit wavevector at launch. Units [deg]",
+                    "type": "number"
+                }
+            }
+        },
+        "shape": {
+            "description": "Beam shape at launch",
+            "type": "object",
+            "properties": {
+                "amplitude": {
+                    "description": "Amplitude ellipse (E-field amplitude 1/e-fold on-axis value)",
+                    "type": "object",
+                    "properties": {
+                        "w": {
+                            "description": "Semi-axes of the ellipse. Units [m]",
+                            "type": "array",
+                            "items": {"type": "number", "exclusiveMinimum": 0},
+                            "minItems": 2,
+                            "maxItems": 2
+                        },
+                        "phi": {"$ref": "#/$defs/rotAngle"}
+                    }
+                },
+                "phase": {
+                    "description": "Phase ellipse (wavefront curvature)",
+                    "type": "object",
+                    "properties": {
+                        "invR": {
+                            "description": "Principal curvatures of the phase front. Units [m^-1]",
+                            "type": "array",
+                            "items": {"type": "number"},
+                            "minItems": 2,
+                            "maxItems": 2
+                        },
+                        "phi": {"$ref": "#/$defs/rotAngle"}
+                    }
+                }        
+            }
+        }
+    },
+    "$defs": {
+        "polEllipse": {
+            "description": "Angles defining an elliptical polarization",
+            "type": "object",
+            "properties": {
+                "psi": {
+                    "description": "Polarization ellipse orientation.\\nThe angle is measured counter-clockwise angle from x' to the polarization\\nellipse major axis in a local right-handed Cartesian frame (x',y',z')\\nwith z' parallel to the beam axis direction k, and x' in the horizontal\\nplane of the global frame (i.e., x'.z=0). Units [deg]",
+                    "type": "number"
+                },
+                "chi": {
+                    "description": "Polarization ellipticity.\\n|tan(chi)| = b/a ≤ 1 is the ratio of the polarization ellipse semi-axes\\nsign(chi) = +1 for a right-handed wave (i.e., electric field rotating\\nfrom x' to y' at fixed z') and -1 for a left-handed wave. Units [deg]",
+                    "type": "number"
+                }
+            }
+        },
+        "rotAngle": {
+            "description": "Ellipse orientation. The angle is measured counter-clockwise from x' to\\nthe first principal direction, in a local right-handed Cartesian frame\\n(x',y',z') with z' parallel to the beam axis direction k, and x' in the\\nhorizontal plane of the global frame (i.e., x'.z=0). Units [deg]",
+            "type": "number"
+        }
+    }
+}
diff --git a/schemas/cocos.schema.json b/schemas/cocos.schema.json
new file mode 100644
index 0000000..39e2a41
--- /dev/null
+++ b/schemas/cocos.schema.json
@@ -0,0 +1,10 @@
+{
+    "$id": "https://www.istp-cnr.it/gray/schemas/cocos",
+    "$schema": "https://json-schema.org/draft/2020-12/schema",
+    "title": "COCOS Tokamak COordinate COnventions code",
+    "type": "integer",
+    "oneOf": [
+        {"minimum": 1, "maximum": 8},
+        {"minimum": 11, "maximum": 18}
+    ]
+}
diff --git a/schemas/coordscart.schema.json b/schemas/coordscart.schema.json
new file mode 100644
index 0000000..4a300e7
--- /dev/null
+++ b/schemas/coordscart.schema.json
@@ -0,0 +1,20 @@
+{
+    "$id": "https://www.istp-cnr.it/gray/schemas/coordscart",
+    "$schema": "https://json-schema.org/draft/2020-12/schema",
+    "title": "Cartesian coordinates in right-handed reference (x, y, z)",
+    "type": "object",
+    "properties": {
+        "x": {
+            "description": "x coordinate. Units [m]",
+            "type": "number"
+        },
+        "y": {
+            "description": "y coordinate. Units [m]",
+            "type": "number"
+        },
+        "z": {
+            "description": "z coordinate. Units [m]",
+            "type": "number"
+        }
+    }
+}
diff --git a/schemas/coordscyl.schema.json b/schemas/coordscyl.schema.json
new file mode 100644
index 0000000..80ea637
--- /dev/null
+++ b/schemas/coordscyl.schema.json
@@ -0,0 +1,23 @@
+{
+    "$id": "https://www.istp-cnr.it/gray/schemas/coordscyl",
+    "$schema": "https://json-schema.org/draft/2020-12/schema",
+    "title": "Coordinates in a cylindrical reference (R, phi, z)",
+    "type": "object",
+    "properties": {
+        "cocos": {"$ref": "cocos"},
+        "r": {
+            "description": "Major radius. Units [m]",
+            "type": "number",
+            "minimum": 0
+        },
+        "phi": {
+            "description": "Toroidal angle. Units [deg]",
+            "type": "number",
+            "default": 0
+        },
+        "z": {
+            "description": "Vertical coordinate. Units [m]",
+            "type": "number"
+        }
+    }
+}
diff --git a/schemas/coreprof.schema.json b/schemas/coreprof.schema.json
new file mode 100644
index 0000000..6a47885
--- /dev/null
+++ b/schemas/coreprof.schema.json
@@ -0,0 +1,28 @@
+{
+    "$id": "https://www.istp-cnr.it/gray/schemas/coreprof",
+    "$schema": "https://json-schema.org/draft/2020-12/schema",
+    "title": "Tabulated core plasma profiles",
+    "type": "object",
+    "properties": {
+        "psiNorm": {
+            "description": "Normalized poloidal magnetic flux. 0 = magnetic axis, 1 = boundary. Units [-]",
+            "$ref": "grid1d",
+            "minimum": 0
+        },
+        "ne": {
+            "description": "Electron density. Units [10^19 m^-3]",
+            "$ref": "number1d",
+            "minimum": 0
+        },
+        "te": {
+            "description": "Electron temperature. Units [keV]",
+            "$ref": "number1d",
+            "minimum": 0
+        },
+        "zEff": {
+            "description": "Effective ion charge. Units [-]",
+            "$ref": "number1d",
+            "minimum": 0
+        }
+    }
+}
diff --git a/schemas/equilibrium.schema.json b/schemas/equilibrium.schema.json
new file mode 100644
index 0000000..8318ce7
--- /dev/null
+++ b/schemas/equilibrium.schema.json
@@ -0,0 +1,65 @@
+{
+    "$id": "https://www.istp-cnr.it/gray/schemas/equilibrium",
+    "$schema": "https://json-schema.org/draft/2020-12/schema",
+    "title": "Numerical magnetic equilibrium",
+    "type": "object",
+    "properties": {
+        "cocos": {"$ref": "cocos"},
+        "psiNorm1d": {
+            "description": "Normalized poloidal magnetic flux on the grid of the 1D profiles. 0 = magnetic axis, 1 = boundary. Units [-]",
+            "$ref": "grid1d",
+            "minimum": 0
+        },
+        "fPol": {
+            "description": "Poloidal current function f(psi) = B_phi * R. Units [T.m]",
+            "$ref": "number1d"
+        },
+        "q": {
+            "description": "Safety factor. Units [-]",
+            "$ref": "number1d"
+        },
+        "rGrid": {
+            "description": "Major radius on the rows of the rectangular grid of the poloidal flux 2D map. Units [m]",
+            "$ref": "grid1d"
+        },
+        "zGrid": {
+            "description": "Vertical coordinate on the columns of the rectangular grid of the poloidal flux 2D map. Units [m]",
+            "$ref": "grid1d"
+        },
+        "psi2d": {
+            "description": "Poloidal magnetic flux on a rectangular (R,z) grid in row-major order:\\n`psi2d`[i][:] is a slice at z = `zGrid`[i];\\n`psi2d`[:][j] is a slice at R = `rGrid`[j].\\nUnits [Wb] or [Wb/rad], depending on COCOS.",
+            "$ref": "number2d"
+        },
+        "psiAx": {
+            "description": "Poloidal flux at the magnetic axis. Units [Wb] or [Wb/rad] depending on COCOS.",
+            "type": "number"
+        },
+        "psiBnd": {
+            "description": "Poloidal flux at the boundary. Units [Wb] or [Wb/rad] depending on COCOS.",
+            "type": "number"
+        },
+        "rAx": {
+            "description": "Magnetic axis major radius. Units [m]",
+            "type": "number",
+            "exclusiveMinimum": 0
+        },
+        "zAx": {
+            "description": "Magnetic axis vertical coordinate. Units [m]",
+            "type": "number"
+        },
+        "boundary": {
+            "description": "Plasma boundary contour in the Rz-plane",
+            "$ref": "rzpolygon"
+        },
+        "currPhi": {
+            "description": "Toroidal plasma current enclosed by the boundary. Units [A].",
+            "type": "number"
+        },
+        "bVac0": {
+            "description": "Vacuum magnetic field at the reference major radius R = `r0`. Units [T]",
+            "type": "number"},
+        "r0": {
+            "description": "Reference major radius for the vacuum magnetic field `bVac0`. Units [m]",
+            "type": "number"}
+    }
+}
diff --git a/schemas/grid1d.json b/schemas/grid1d.json
new file mode 100644
index 0000000..6a99494
--- /dev/null
+++ b/schemas/grid1d.json
@@ -0,0 +1,8 @@
+{
+    "$id": "https://www.istp-cnr.it/gray/schemas/grid1d",
+    "$schema": "https://json-schema.org/draft/2020-12/schema",
+    "title": "1D array of unique numbers",
+    "type": "array",
+    "items": {"type": "number"},
+    "uniqueItems": true
+}
diff --git a/schemas/io.schema.json b/schemas/io.schema.json
new file mode 100644
index 0000000..15b1cca
--- /dev/null
+++ b/schemas/io.schema.json
@@ -0,0 +1,24 @@
+{
+    "$id": "https://www.istp-cnr.it/gray/schemas/io",
+    "$schema": "https://json-schema.org/draft/2020-12/schema",
+    "title": "GRAY Input/Output data",
+    "type": "object",
+    "properties": {
+        "inputs": {
+            "type": "object",
+            "properties": {
+                "equil" : {"$ref" : "equilibrium"},
+                "coreProf" : {"$ref" : "coreprof"},
+                "beam" : {"$ref" : "beam"},
+                "wall" : {"$ref" : "wall"}
+            }
+        },
+        "params" : {"$ref": "params"},
+        "outputs" : {
+            "type" : "object",
+            "properties" : {
+                "hcdProf": {"constant": null}
+            }
+        }
+    }
+}
\ No newline at end of file
diff --git a/schemas/number1d.schema.json b/schemas/number1d.schema.json
new file mode 100644
index 0000000..4a6c649
--- /dev/null
+++ b/schemas/number1d.schema.json
@@ -0,0 +1,7 @@
+{
+    "$id": "https://www.istp-cnr.it/gray/schemas/number1d",
+    "$schema": "https://json-schema.org/draft/2020-12/schema",
+    "title": "1D array of numbers",
+    "type": "array",
+    "items": {"type": "number"}
+}
diff --git a/schemas/number2d.schema.json b/schemas/number2d.schema.json
new file mode 100644
index 0000000..5f74be2
--- /dev/null
+++ b/schemas/number2d.schema.json
@@ -0,0 +1,7 @@
+{
+    "$id": "https://www.istp-cnr.it/gray/schemas/number2d",
+    "$schema": "https://json-schema.org/draft/2020-12/schema",
+    "title": "2D array of numbers",
+    "type": "array",
+    "items": {"$ref": "number1d"}
+}
diff --git a/schemas/params.schema.json b/schemas/params.schema.json
new file mode 100644
index 0000000..7a60bc9
--- /dev/null
+++ b/schemas/params.schema.json
@@ -0,0 +1,266 @@
+{
+    "$id": "https://www.istp-cnr.it/gray/schemas/params",
+    "$schema": "https://json-schema.org/draft/2020-12/schema",
+    "title": "Code parameters",
+    "type" : "object",
+    "properties": {
+        "raytracing": {
+            "description": "Raytracing parameters",
+            "type": "object",
+            "properties": {
+                "nRayRad": {
+                    "description": "Number of rays in the radial direction",
+                    "type": "integer",
+                    "minimum": 1,
+                    "default": 1
+                },
+                "nRayAng": {
+                    "description": "Number of rays in the angular direction",
+                    "type": "integer",
+                    "minimum": 1,
+                    "default": 1
+                },
+                "rwMax": {
+                    "description": "Normalized beam truncation radius.\\nThe last shell of rays is set at a distance r = `rwmax`⋅w from\\nthe magnetic axis, where w is the 1/e amplitude beam radius.",
+                    "type": "number",
+                    "exclusiveMinimum": 0,
+                    "default": 1.0
+                },
+                "asBeam": {
+                    "description": "`false` for raytracing (Geometrical Optics approximation), `true` for beamtracing (Complex GO)",
+                    "type": "boolean",
+                    "default": false
+                },
+                "dStep": {
+                    "description": "Step length for the numerical integration of the ray trajectories. Units [cm]",
+                    "type": "number",
+                    "exclusiveMinimum": 0
+                },
+                "nStep": {
+                    "description": "Maximum number of integration steps",
+                    "type": "integer",
+                    "minimum": 0,
+                    "default": 12000
+                },
+                "stepVar": {
+                    "description": "Choice of the integration variable. One of:\\n  - `ARCLEN`: arc length (s)\\n  - `TIME`: time (actually c⋅t)\\n  - `PHASE`: phase (actually the real part of the eikonal S_r=k₀⋅φ)",
+                    "enum": ["ARCLEN", "TIME", "PHASE"],
+                    "default": "TIME"
+                },
+                "nPass": {
+                    "description": "Maximum number of crossing (in, out) of the plasma.\\nWhen positive, reflections occur on the plasma limiter provided as input\\n(e.g., via the G-EQDSK file);\\nwhen negative on a simple cylindrical limiter is set at R = `rwall`",
+                    "type": "integer",
+                    "default": 1
+                }
+            }
+        },
+        "ecrh_cd": {
+            "description": "ECRH and current drive parameters",
+            "type":"object",
+            "properties": {
+                "absModel": {
+                    "description": "Choice of the power absorption model. One of:\\n  - `OFF`: no absorption\\n  - `WEAK`: weakly relativistic\\n  - `FULL`: fully relativistic\\n  - `FULL_ALT`: fully relativistic (slower variant)\\nNote: `iwarm` /= `OFF` is required for current drive.",
+                    "enum": ["OFF", "WEAK", "FULL", "FULL_ALT"],
+                    "default": "FULL"
+                },
+                "nLarm": {
+                    "description": "Order of the electron Larmor radius expansion used for the warm dielectric tensor",
+                    "type": "integer",
+                    "minimum": 0,
+                    "default": 5
+                },
+                "nIterMax": {
+                    "description": "Max number of iterations for the solution of the warm dispersion relation.\\nNote: if negative the result of the first iteration will be used in case\\nthe result doesn't converge within |imx| iterations.",
+                    "type": "integer",
+                    "default": -20
+                },
+                "cdModel": {
+                    "description": "Current drive model. One of:\\n  - `OFF`: no current drive\\n  - `COHEN`: Cohen model\\n  - `NO_TRAP`: no trapping\\n  - `NEOCLASS`: Neoclassical with momentum conservation",
+                    "enum": ["OFF", "COHEN", "NO_TRAP", "NEOCLASS"],
+                    "default": "NEOCLASS"
+                }
+            }
+        },
+        "input": {
+            "description": "Input data pre-processing",
+            "type": "object",
+            "properties": {
+                "searchXPoint": {
+                    "description": "Search X point for psi re-normalization.\\nOne of:\\n  - `NO`: do not search\\n  - `TOP`: upper X-point\\n  - `BOTTOM`: lower X-point\\n  - `BOTH`: search both, normalize to the innermost.",
+                    "enum": ["NO", "TOP", "BOTTOM", "BOTH"],
+                    "default": "NO"
+                },
+                "smoothPsi": {
+                    "description": "Tension of the 2D spline for the normalised poloidal flux ψ_n(R,z).\\n0 gives an interpolating spline.",
+                    "type": "number",
+                    "minimum": 0,
+                    "default": 0.005
+                },
+                "smoothFpol": {
+                    "description": "Tension of the 1D spline for the poloidal current function F(ψ)=R⋅B_T.\\n0 gives an interpolating spline.",
+                    "type": "number",
+                    "minimum": 0,
+                    "default": 0.01
+                },
+                "smoothDens": {
+                    "description": "Tension of the 1D spline for the electron density function n_e(ψ).\\n0 gives an interpolating spline.",
+                    "type": "number",
+                    "minimum": 0,
+                    "default": 0.1
+                },
+                "signB": {
+                    "description": "Force the sign of the toroidal field. One of:\\n  - `+1`: counter-clockwise (viewed from above)\\n  - `-1`: clockwise\\n  - `0`: do not force, interpret sign according to input COCOS",
+                    "enum": [-1, 0, 1],
+                    "default": 0
+                },
+                "signI": {
+                    "description": "Force the sign of the toroidal plasma current. One of:\\n  - `+1`: counter-clockwise (viewed from above)\\n  - `-1`: clockwise\\n  - `0`: do not force, interpret sign according to input COCOS",
+                    "enum": [-1, 0, 1],
+                    "default": 0
+                },
+                "factB": {
+                    "description": "Rescaling factor for the magnetic field, applied after sign forcing with `signB`.",
+                    "type": "number",
+                    "default": 1
+                },
+                "factTemp": {
+                    "description": "Rescaling factor for the electron temperature profile.\\nThe combined effect with `factB` depends on the `scalType` parameter.\\n",
+                    "type": "number",
+                    "default": 1
+                },
+                "factDens": {
+                    "description": "Rescaling factor for the electron density profile.\\nThe combined effect with `factB` depends on the `scalType` parameter.\\n",
+                    "type": "number",
+                    "default": 1
+                },
+                "scalType": {
+                    "description": "Model for temperature and density rescaling with the magnetic field. One of:\\n  - `OFF`: don't rescale with B\\n  - `COLLISION`: preserve effective collisionality nustar:\\n    n_e -> n_e⋅`factDens`⋅`factB`^(4/3)\\n    T_e -> T_e⋅`factTemp`⋅`factB`^(2/3)\\n  - `GREENWALD`, preserve Greenwald fraction n_e/n_GW:\\n    n_e -> n_e⋅`factDens`⋅`factB`\\n    T_e -> T_e⋅`factTemp`⋅`factB`",
+                    "enum": ["OFF", "COLLISION", "GREENWALD"],
+                    "default": "OFF"
+                }
+            }
+        },
+        "output": {
+            "description": "Output data parameters",
+            "type": "object",
+            "properties": {
+                "rhoVar": {
+                    "description": "Main radial coordinate to build uniform grid for ECRH&CD profiles. One of:\\n  - `RHO_TOR`: ρ_t = √Φ_n (where Φ_n is the normalised toroidal flux)\\n  - `RHO_POL`: ρ_p = √ψ_n (where ψ_n is the normalised poloidal flux)",
+                    "enum": ["RHO_TOR", "RHO_POL"],
+                    "default": "RHO_POL"
+                },
+                "nRho": {
+                    "description": "Number of points in the radial grid",
+                    "type": "integer",
+                    "minimum": 2,
+                    "default": 501
+                },
+                "iStepProj": {
+                    "description": "Step subsampling factor for the beam cross section (units 8, 12)",
+                    "type": "integer",
+                    "default": 5
+                },
+                "iStepTraj": {
+                    "description": "Step subsampling factor for the outer rays data (unit 33)",
+                    "type": "integer",
+                    "default": 5
+                }
+            }
+        },
+        "beam": {
+            "description": "Beam launch parameters setup from configuration file",
+            "type": "object",
+            "properties": {
+                "filename": {
+                    "description": "Filepath (relative to the parameters file) for the beam properties description, possibly in a system with one or more degrees of freedom",
+                    "type": "string"
+                },
+                "nSteerAxes": {
+                    "description": "Number of degrees of freedom in the system described by the configuration file",
+                    "type": "integer",
+                    "minimum": 0,
+                    "maximum": 2
+                },
+                "steering": {
+                    "description": "Steering values used to select the beam parameters from the configuration file. The number of required values is set with the `nSteerAxis` parameter. Units [a.u.]",
+                    "$ref": "number1d"
+                },
+                "index": {
+                    "description": "Position index of the selected beam in the configuration file, 1-based.",
+                    "type": "integer",
+                    "minimum": 1,
+                    "default": 1
+                },
+                "power": {"$ref": "beam#/power"},
+                "polarization": {"$ref": "beam#/polarization"}
+            }
+        },
+        "equilibrium": {
+            "description": "Magnetic field configuration read from external file",
+            "type": "object",
+            "properties": {
+                "filename": {
+                    "description": "Filepath (relative to the parameters file) of the equilibrium data",
+                    "type": "string"
+                },
+                "equilType": {
+                    "description": "Type of magnetic equilibrium description. One of:\\n  - `VACUUM`: vacuum (no plasma)\\n  - `ANALYTICAL`: analytical model\\n  - `EQDSK_FULL`: G-EQDSK format - data valid on the whole domain\\n  - `EQDSK_PARTIAL`: G-EQDSK format - data valid only inside the LCFS",
+                    "enum": ["VACUUM", "ANALYTICAL", "EQDSK_FULL", "EQDSK_PARTIAL"],
+                    "default": "EQDSK_FULL"
+                },
+                "cocos": {
+                    "description": "COCOS index of the equilibrium data (G-EQDSK only)",
+                    "$ref" : "cocos",
+                    "default": 3
+                },
+                "hasPsiNorm": {
+                    "description": "Whether the 2D poloidal flux is normalised (G-EQDSK only)",
+                    "type": "boolean",
+                    "default": false
+                },
+                "hasDesc": {
+                    "description": "Whether the header starts with a description/identification string (G-EQDSK only)",
+                    "type": "boolean",
+                    "default": true
+                },
+                "hasFreeFormat": {
+                    "description": "Whether the records have variable length (G-EQDSK only)\\nNote: some non-compliant programs output numbers formatted with variable\\nlength instead of using the single (5e16.9) specifier.",
+                    "type": "boolean",
+                    "default": false
+                }
+            }
+        },
+        "profiles": {
+            "description": "(input) plasma profiles parameters",
+            "type": "object",
+            "properties": {
+                "filename": {
+                    "description": "Filepath (relative to the parameters file) of the plasma profiles data",
+                    "type": "string"
+                },
+                "profType": {
+                    "description": "Type of plasma profiles description. One of:\\n  - `ANALYTIC`: analytical model\\n  - `NUMERIC: tabulated data",
+                    "enum": ["ANALYTIC", "NUMERIC"],
+                    "default": "NUMERIC"
+                },
+                "rhoDef": {
+                    "description": "Plasma profiles radial coordinate in input file\\n(`profType`==`NUMERIC` only). One of:\\n  - `RHO_TOR`: ρ_t = √Φ_n (where Φ_n is the normalised toroidal flux)\\n  - `RHO_POL`: ρ_p = √ψ_n (where ψ_n is the normalised poloidal flux)\\n  - `PSI_N`: normalised poloidal flux ψ_n",
+                    "enum": ["RHO_TOR", "RHO_POL", "PSI_N"],
+                    "default": "PSI_N"
+                }
+            }
+        },
+        "misc": {
+            "description": "Other parameters",
+            "type": "object",
+            "properties": {
+                "rWall": {
+                    "description": "Radius of the inner wall. Used to build a simple cylindrical limiter for\\nreflections (only when `nPass`<0), and to discard invalid solutions\\n(at R < `rWall`) when reconstructing the flux surfaces contours. Units [m]",
+                    "type": "number",
+                    "minimum": 0,
+                    "default": 0
+                }
+            }
+        }                
+    }
+}
\ No newline at end of file
diff --git a/schemas/rzpolygon.schema.json b/schemas/rzpolygon.schema.json
new file mode 100644
index 0000000..201cb59
--- /dev/null
+++ b/schemas/rzpolygon.schema.json
@@ -0,0 +1,19 @@
+{
+    "$id": "https://www.istp-cnr.it/gray/schemas/rzpolygon",
+    "$schema": "https://json-schema.org/draft/2020-12/schema",
+    "title": "Polygon in the poloidal Rz-plane",
+    "type": "object",
+    "properties": {
+        "r": {
+            "description": "Radial coordinate. Units [m]",
+            "allOf": [
+                {"$ref": "number1d"},
+                {"items": {"minimum": 0}}
+            ]
+        },
+        "z": {
+            "description": "Vertical coordinate. Units [m]",
+            "$ref": "number1d"
+        }
+    }
+}
diff --git a/schemas/validate.py b/schemas/validate.py
new file mode 100644
index 0000000..694f5f2
--- /dev/null
+++ b/schemas/validate.py
@@ -0,0 +1,53 @@
+import argparse
+import json
+import jsonschema
+import jsonschema.protocols
+import jsonschema.validators
+from jsonschema import Draft202012Validator
+from jsonschema.exceptions import SchemaError, ValidationError
+from referencing import Registry, Resource
+from referencing.jsonschema import DRAFT202012
+
+parser = argparse.ArgumentParser(
+    description="Validate a JSON document against a JSON schema"
+)
+parser.add_argument("file", type=str, help="the JSON file to validate")
+parser.add_argument("-s", "--schema", required=True, 
+                    help="file containing the schema definition."
+                    )
+parser.add_argument("-r", "--resource", action="append", default=[],
+                    help="additional schemas to be added to the registry " +
+                    "for reference resolution. Multiple schema files can " +
+                    "be added by specifying the option multiple times.")
+
+if __name__ == "__main__":
+    args = parser.parse_args()
+    # Load the schema and any additional resources and add them to the registry for reference resolution
+    # The schema is last in the list: it will remain stored in schema_dict at the end of the for loop
+    registry = Registry()
+    for schema_file in (*args.resource, args.schema):
+        with open(file=schema_file, mode="r") as f:
+            schema = json.load(f)
+        resource = Resource.from_contents(
+            contents=schema,
+            default_specification=DRAFT202012
+        )
+        registry = resource @ registry
+    # Load the JSON document to validate
+    with open(file=args.file, mode="r") as f:
+        document = json.load(f)
+    # Set the validator with the desired schema and check the schema itself before validating the document
+    validator = jsonschema.validators.validator_for(schema)(schema, registry=registry)
+    try:
+        validator.check_schema(schema)
+    except SchemaError as e:
+        print("Schema check failed.")
+        print(f"{e.message}")
+        exit(1)
+    try:
+        validator.validate(document)
+        print("Valid!")
+    except ValidationError as e:
+        print("Validation failed.")
+        print(f"{e.message}")
+        exit(1)
diff --git a/schemas/wall.schema.json b/schemas/wall.schema.json
new file mode 100644
index 0000000..5af27e0
--- /dev/null
+++ b/schemas/wall.schema.json
@@ -0,0 +1,12 @@
+{
+    "$id": "https://www.istp-cnr.it/gray/schemas/wall",
+    "$schema": "https://json-schema.org/draft/2020-12/schema",
+    "title": "First wall description",
+    "type": "object",
+    "properties": {
+        "contour2d": {
+            "description": "Axisymmetric approximation. The polygon is assumed closed even if the first and the last point do not match.",
+            "$ref": "rzpolygon"
+        }
+    }
+}