diff --git a/CLAUDE.md b/CLAUDE.md
index 249e395..fb77280 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -14,9 +14,11 @@
 # MANDATORY WORKFLOW
 1. Only one TODO.md feature at a time
 2. Create a git branch for each new feature
-3. After making any change
+3. Implement then new feature, and create tests for the new feature
+4. After making any change
   - Allways pass all the tests and integration tests
   - Build the application for linux and web-server
   - Launch the apllication for web-server, with a timeout of 60s
-4. If any test or build or web-server launch fails, go to step 3
-5. Dont merge the feature branch into master, the work will be reviewed by a human.
+5. If any test or build or web-server launch fails, go to step 3
+6. Change TODO.md. Mark the task with [R], than means than the work will be reviewed by a human.
+7. Dont merge the feature branch into master, the work will be reviewed by a human.
diff --git a/TODO.md b/TODO.md
index 2bba3ad..894a039 100644
--- a/TODO.md
+++ b/TODO.md
@@ -1,6 +1,10 @@
+# Conventions
 [ ] Means not done
-[x] Means done
+[R] Means done, but needs a human review 
+[X] Means done
 
+
+# List of tasks
 - [X] Unify error reporting. Create class ErrorHandler that get notified of every catched exception. This class prints the exception in stdout.
 - [X] Make formula description collapsable in FormulaScreen. Initialy, the description is visible, but the user can hide it.
 - Refactor formula and unit loading:
@@ -11,8 +15,8 @@
   - [X] Change createDefaultCorpus to use loadFormulaElements instead of loadUnits and loadFormula. Make loadUnits and loadFormula private.
 - [X] Use a single table in database `FORMULAELEMENT` to store formulas and units. The table contains only two columns: autonumeric id and text.
 - Drift files have a lot of duplicate code. "web" version is the same as native version, only _openConnection is diferrent. Refactor to not duplicate code.
-- [ ] Create Formula.toStringLiteral. It is the reverse of Formula.fromSet( Formula.fromArrayStringLiteral(string)[0] )
-- [ ] Create UnitSpec.toStringLiteral, like Formula.toStringLiteral
+- [X] Create Formula.toStringLiteral. It is the reverse of Formula.fromSet( Formula.fromArrayStringLiteral(string)[0] )
+- [X] Create UnitSpec.toStringLiteral, like Formula.toStringLiteral
 - Database file location:
   - [ ] In linux, the sqlite database file will be located following rules at https://specifications.freedesktop.org/basedir/latest/
   - [ ] In Windows, the sqlite database file will be in %appdata%/Roaming
diff --git a/lib/formula_models.dart b/lib/formula_models.dart
index 42504a0..34b7499 100644
--- a/lib/formula_models.dart
+++ b/lib/formula_models.dart
@@ -134,6 +134,28 @@ class UnitSpec {
     return units.toList(growable: false);
   }
 
+  /// Creates a string literal representation of the UnitSpec that can be parsed
+  /// by the D4RT parser to recreate the same UnitSpec object.
+  String toStringLiteral() {
+    final buffer = StringBuffer('{');
+    buffer.write('"name": "$name", "symbol": "$symbol"');
+    
+    if (name == baseUnit && factorFromUnitToBase == 1) {
+      // This is a base unit
+      buffer.write(', "isBase": true');
+    } else {
+      buffer.write(', "baseUnit": "$baseUnit"');
+      
+      if (factorFromUnitToBase != null) {
+        buffer.write(', "factor": $factorFromUnitToBase');
+      } else if (codeFromUnitToBase != null && codeFromBaseToUnit != null) {
+        buffer.write(', "toBase": "$codeFromUnitToBase", "fromBase": "$codeFromBaseToUnit"');
+      }
+    }
+    
+    buffer.write('}');
+    return buffer.toString();
+  }
 }
 
 class VariableSpec {
@@ -169,6 +191,30 @@ class VariableSpec {
 
   @override
   int get hashCode => Object.hash(unit, name, values != null ? const DeepCollectionEquality().hash(values!) : 0);
+
+  /// Creates a string literal representation of the VariableSpec that can be parsed
+  /// by the D4RT parser.
+  String toStringLiteral() {
+    final buffer = StringBuffer('{');
+    buffer.write('"name": "$name"');
+    
+    if (unit != null) {
+      buffer.write(', "unit": "$unit"');
+    }
+    
+    if (values != null && values!.isNotEmpty) {
+      buffer.write(', "values": [${values!.map((value) {
+        if (value is String) {
+          return '"$value"';
+        } else {
+          return value.toString();
+        }
+      }).join(", ")}]');
+    }
+    
+    buffer.write('}');
+    return buffer.toString();
+  }
 }
 
 class Formula {
@@ -282,4 +328,28 @@ class Formula {
       d4rtCode: d4rtCode,
     );
   }
+
+  /// Creates a string literal representation of the Formula that can be parsed
+  /// by the D4RT parser to recreate the same Formula object.
+  String toStringLiteral() {
+    final inputStrings = input.map((varSpec) => varSpec.toStringLiteral()).toList();
+    
+    final buffer = StringBuffer('{');
+    buffer.write('"name": "$name"');
+    
+    if (description != null) {
+      buffer.write(', "description": "$description"');
+    }
+    
+    buffer.write(', "input": [${inputStrings.join(", ")}]');
+    buffer.write(', "output": ${output.toStringLiteral()}');
+    buffer.write(', "d4rtCode": ${d4rtCode.contains('\n') || d4rtCode.contains('"') ? 'r"""$d4rtCode"""' : '"$d4rtCode"'}');
+    
+    if (tags.isNotEmpty) {
+      buffer.write(', "tags": [${tags.map((tag) => '"$tag"').join(", ")}]');
+    }
+    
+    buffer.write('}');
+    return buffer.toString();
+  }
 }
diff --git a/test/formula_models_test.dart b/test/formula_models_test.dart
index 7b25cb4..20e5319 100644
--- a/test/formula_models_test.dart
+++ b/test/formula_models_test.dart
@@ -99,7 +99,7 @@ void main() {
       "d4rtCode": '''
               F = a * m;
           '''
-    }    
+    }
     """;
 
     final formula = Formula.fromStringLiteral(literal);
@@ -113,6 +113,56 @@ void main() {
     expect(result, 98.0); // F = m * a = 10 * 9.8 = 98 N
   });
 
+  test('Formula.toStringLiteral creates reversible string', () {
+    final originalFormula = Formula(
+      name: "Test Formula",
+      description: "A test formula for toStringLiteral",
+      input: [
+        VariableSpec(name: 'x', unit: 'meter'),
+        VariableSpec(name: 'y', unit: 'second', values: ['1', '2', '3']) // Using strings to match D4RT parsing behavior
+      ],
+      output: VariableSpec(name: 'result', unit: 'meter_per_second'),
+      d4rtCode: 'result = x / y;',
+      tags: ['test', 'simple'],
+    );
+
+    final literal = originalFormula.toStringLiteral();
+    final parsedFormula = Formula.fromStringLiteral(literal);
+
+    expect(parsedFormula.name, originalFormula.name);
+    expect(parsedFormula.description, originalFormula.description);
+    expect(parsedFormula.input.length, originalFormula.input.length);
+    expect(parsedFormula.output, originalFormula.output);
+    expect(parsedFormula.d4rtCode, originalFormula.d4rtCode);
+    expect(parsedFormula.tags, originalFormula.tags);
+
+    // Check inputs individually
+    for (int i = 0; i < originalFormula.input.length; i++) {
+      expect(parsedFormula.input[i].name, originalFormula.input[i].name);
+      expect(parsedFormula.input[i].unit, originalFormula.input[i].unit);
+      expect(parsedFormula.input[i].values, originalFormula.input[i].values);
+    }
+  });
+
+  test('UnitSpec.toStringLiteral creates reversible string', () {
+    final originalUnit = UnitSpec(
+      name: "test_unit",
+      baseUnit: "base_unit",
+      symbol: "tu",
+      factorFromUnitToBase: 10.0,
+    );
+
+    final literal = originalUnit.toStringLiteral();
+    final parsedList = parseD4rtLiteral('[${literal}]');
+    final parsedMap = parsedList[0] as Map<Object?, Object?>;
+    final parsedUnit = UnitSpec.fromSet(parsedMap);
+
+    expect(parsedUnit.name, originalUnit.name);
+    expect(parsedUnit.baseUnit, originalUnit.baseUnit);
+    expect(parsedUnit.symbol, originalUnit.symbol);
+    expect(parsedUnit.factorFromUnitToBase, originalUnit.factorFromUnitToBase);
+  });
+
   group('APGAR Score', () {
     test('evaluates APGAR score formula - Normal case', () async {
       final corpus = await testCorpus;