new api endpoint to get supported strategy operators

api/README.md

@@ -429,6 +429,32 @@ Returns if the provided strategy predicate is valid and well-formatted. If the p
 | 400 | `the predicate provided is not valid` | 4015 | 
 | 500 | `error encoding validated strategy predicate` | 5024 | 
 
+### GET `/strategies/predicate/operators`
+Returns the list of supported operators to build strategy predicates.
+
+- 📥 response:
+
+```json
+{
+    "operators": [
+        {
+            "description": "logical operator that returns the common token holders between symbols with fixed balance to 1",
+            "tag": "AND"
+        },
+        {
+            "description": "logical operator that returns the token holders of both symbols with fixed balance to 1",
+            "tag": "OR"
+        }
+    ]
+}
+```
+
+- ⚠️ errors:
+
+| HTTP Status  | Message | Internal error |
+|:---:|:---|:---:|
+| 500 | `error encoding supported strategy predicate operators` | 5027 | 
+
 ## Censuses
 
 ### POST `/censuses`

api/errors.go

@@ -233,4 +233,9 @@ var (
 		HTTPstatus: apirest.HTTPstatusInternalErr,
 		Err:        fmt.Errorf("error evaluating strategy predicate"),
 	}
+	ErrEncodeStrategyPredicateOperators = apirest.APIerror{
+		Code:       5027,
+		HTTPstatus: apirest.HTTPstatusInternalErr,
+		Err:        fmt.Errorf("error encoding supported strategy predicate operators"),
+	}
 )

api/strategies.go

@@ -38,6 +38,10 @@ func (capi *census3API) initStrategiesHandlers() error {
 		api.MethodAccessTypePublic, capi.validateStrategyPredicate); err != nil {
 		return err
 	}
+	if err := capi.endpoint.RegisterMethod("/strategies/predicate/operators", "GET",
+		api.MethodAccessTypePublic, capi.supportedStrategyPredicateOperators); err != nil {
+		return err
+	}
 	return nil
 }
 
@@ -305,3 +309,15 @@ func (capi *census3API) validateStrategyPredicate(msg *api.APIdata, ctx *httprou
 	}
 	return ctx.Send(res, api.HTTPstatusOK)
 }
+
+// supportedStrategyPredicateOperators function handler returns the information
+// of the current supported operators to build strategy predicates.
+func (capi *census3API) supportedStrategyPredicateOperators(msg *api.APIdata, ctx *httprouter.HTTPContext) error {
+	res, err := json.Marshal(map[string]any{
+		"operators": strategyoperators.ValidOperators,
+	})
+	if err != nil {
+		return ErrEncodeStrategyPredicateOperators.WithErr(err)
+	}
+	return ctx.Send(res, api.HTTPstatusOK)
+}

api/strategyoperators/operators.go

@@ -21,6 +21,18 @@ const (
 // ValidOperatorsTags variable contains the supported operator tags
 var ValidOperatorsTags = []string{ANDTag, ORTag}
 
+// ValidOperators variable contains the information of the supported operators
+var ValidOperators = []map[string]string{
+	{
+		"tag":         ANDTag,
+		"description": "logical operator that returns the common token holders between symbols with fixed balance to 1",
+	},
+	{
+		"tag":         ORTag,
+		"description": "logical operator that returns the token holders of both symbols with fixed balance to 1",
+	},
+}
+
 type TokenInformation struct {
 	ID         string
 	ChainID    uint64