Phase 3: Stored Procedure Parameter Substitution (auto-embed: true)

schemas/dab.draft.schema.json

@@ -1245,7 +1245,8 @@
                               "name": { "type": "string", "description": "Parameter name" },
                               "required": { "$ref": "#/$defs/boolean-or-string", "description": "Is parameter required" },
                               "default": { "type": ["string", "number", "boolean", "null"], "description": "Default value" },
-                              "description": { "type": "string", "description": "Parameter description. Since descriptions for multiple parameters are provided as a comma-separated string, individual parameter descriptions must not contain a comma (',')." }
+                              "description": { "type": "string", "description": "Parameter description. Since descriptions for multiple parameters are provided as a comma-separated string, individual parameter descriptions must not contain a comma (',')." },
+                              "auto-embed": { "$ref": "#/$defs/boolean-or-string", "description": "When true, the parameter value (text) is automatically converted to an embedding vector via the configured embedding service before being passed to the stored procedure. The target stored-procedure parameter must be a string-compatible type (e.g., NVARCHAR/VARCHAR); the stored procedure is responsible for any conversion to a native vector type if needed (e.g., CAST(@param AS VECTOR(N)) on Azure SQL). Requires runtime.embeddings to be configured and enabled.", "default": false }
                             }
                           }
                         }

src/Azure.DataApiBuilder.Mcp/BuiltInTools/DescribeEntitiesTool.cs

@@ -448,7 +448,7 @@ private static bool ShouldIncludeEntity(string entityName, HashSet<string>? enti
 
             if (entity.Source.Type == EntitySourceType.StoredProcedure)
             {
-                info["parameters"] = BuildParameterMetadataInfo(databaseObject);
+                info["parameters"] = BuildParameterMetadataInfo(databaseObject, entity.Source.Parameters);
             }
 
             info["permissions"] = BuildPermissionsInfo(entity, currentUserRole);
@@ -511,7 +511,7 @@ private static List<object> BuildFieldMetadataInfo(List<FieldMetadata>? fields)
         /// <returns>A list whose elements are dictionaries (one per parameter), each with the keys
         /// <c>name</c>, <c>required</c>, <c>default</c>, and <c>description</c>.</returns>
         /// <exception cref="InvalidOperationException">Thrown when <paramref name="databaseObject"/> is not a <see cref="DatabaseStoredProcedure"/> with a populated <see cref="StoredProcedureDefinition"/>.</exception>
-        private static List<object> BuildParameterMetadataInfo(DatabaseObject? databaseObject)
+        private static List<object> BuildParameterMetadataInfo(DatabaseObject? databaseObject, List<ParameterMetadata>? configParams)
         {
             IReadOnlyDictionary<string, ParameterDefinition>? dbParameters =
                 (databaseObject as DatabaseStoredProcedure)?.StoredProcedureDefinition?.Parameters
@@ -522,20 +522,23 @@ private static List<object> BuildParameterMetadataInfo(DatabaseObject? databaseO
             List<object> result = new(dbParameters.Count);
             foreach ((string parameterName, ParameterDefinition definition) in dbParameters)
             {
-                result.Add(BuildParameterEntry(parameterName, definition));
+                bool autoEmbed = configParams?.FirstOrDefault(p => p.Name == parameterName)?.AutoEmbed ?? false;
+                result.Add(BuildParameterEntry(parameterName, definition, autoEmbed));
             }
 
             return result;
         }
 
         private static Dictionary<string, object?> BuildParameterEntry(
             string name,
-            ParameterDefinition definition) => new()
+            ParameterDefinition definition,
+            bool autoEmbed) => new()
             {
                 ["name"] = name,
                 ["required"] = definition.Required ?? true,
                 ["default"] = definition.Default,
-                ["description"] = definition.Description ?? string.Empty
+                ["description"] = definition.Description ?? string.Empty,
+                ["autoEmbed"] = autoEmbed
             };
 
         /// <summary>

src/Azure.DataApiBuilder.Mcp/Core/DynamicCustomTool.cs

@@ -363,10 +363,15 @@ private JsonElement BuildInputSchema()
             Dictionary<string, object> properties = new();
             foreach ((string paramName, ParameterDefinition paramDef) in spDefinition.Parameters)
             {
+                // Surface the auto-embed indicator in the description when the config marks
+                // this parameter as auto-embed:true. DB metadata doesn't carry this flag, so
+                // we cross-reference the config-side ParameterMetadata.
+                bool isAutoEmbed = _entity.Source.Parameters?.FirstOrDefault(p => p.Name == paramName)?.AutoEmbed ?? false;
+
                 Dictionary<string, object> paramSchema = new()
                 {
                     ["type"] = MapSystemTypeToJsonSchemaType(paramDef.SystemType),
-                    ["description"] = BuildParameterDescription(paramName, paramDef)
+                    ["description"] = BuildParameterDescription(paramName, paramDef, isAutoEmbed)
                 };
 
                 properties[paramName] = paramSchema;
@@ -399,10 +404,21 @@ private JsonElement BuildInputSchemaFromConfig()
 
                 foreach (ParameterMetadata param in _entity.Source.Parameters)
                 {
+                    // Note: Parameter type information is not available in ParameterMetadata,
+                    // so we allow multiple JSON types to match the behavior of GetParameterValue
+                    // that handles string, number, boolean, and null values. Runtime
+                    // validation (ParameterEmbeddingHelper for auto-embed, SQL Server for the
+                    // rest) rejects values that the sproc parameter can't accept.
+                    string description = param.Description ?? $"Parameter {param.Name}";
+                    if (param.AutoEmbed)
+                    {
+                        description += " (auto-embed: DAB converts this value to an embedding before execution)";
+                    }
+
                     properties[param.Name] = new Dictionary<string, object>
                     {
                         ["type"] = new[] { "string", "number", "boolean", "null" },
-                        ["description"] = param.Description ?? $"Parameter {param.Name}"
+                        ["description"] = description
                     };
                 }
             }
@@ -455,15 +471,23 @@ private static object MapSystemTypeToJsonSchemaType(Type? systemType)
         /// <summary>
         /// Builds a description string for a parameter using DB metadata.
         /// Uses ParameterDefinition.Description when available, falling back to generic text.
+        /// When <paramref name="isAutoEmbed"/> is true, appends the auto-embed indicator
+        /// so MCP clients see that DAB will convert the value to an embedding before
+        /// executing the stored procedure.
         /// </summary>
-        private static string BuildParameterDescription(string paramName, ParameterDefinition paramDef)
+        private static string BuildParameterDescription(string paramName, ParameterDefinition paramDef, bool isAutoEmbed = false)
         {
             string description = paramDef.Description ?? $"Parameter {paramName}";
             if (paramDef.HasConfigDefault)
             {
                 description += $" (default: {paramDef.ConfigDefaultValue})";
             }
 
+            if (isAutoEmbed)
+            {
+                description += " (auto-embed: DAB converts this value to an embedding before execution)";
+            }
+
             return description;
         }
 

src/Cli.Tests/AddEntityTests.cs

@@ -52,6 +52,7 @@ public Task AddNewEntityWhenEntitiesEmpty()
                 parametersDescriptionCollection: null,
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -91,6 +92,7 @@ public Task AddNewEntityWhenEntitiesNotEmpty()
                 parametersDescriptionCollection: null,
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -133,6 +135,7 @@ public void AddDuplicateEntity()
                 parametersDescriptionCollection: null,
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -179,6 +182,7 @@ public Task AddEntityWithAnExistingNameButWithDifferentCase()
                 parametersDescriptionCollection: null,
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -220,6 +224,7 @@ public Task AddEntityWithCachingEnabled()
                 parametersDescriptionCollection: null,
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -267,6 +272,7 @@ public Task AddEntityWithPolicyAndFieldProperties(
                 parametersDescriptionCollection: null,
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -310,6 +316,7 @@ public Task AddNewEntityWhenEntitiesWithSourceAsStoredProcedure()
                 parametersDescriptionCollection: ["This is a test parameter description."],
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -352,6 +359,7 @@ public Task TestAddStoredProcedureWithRestMethodsAndGraphQLOperations()
                 parametersDescriptionCollection: null,
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -390,6 +398,7 @@ public void AddEntityWithDescriptionAndVerifyInConfig()
                 parametersDescriptionCollection: null,
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -455,6 +464,7 @@ public void TestAddNewEntityWithSourceObjectHavingValidFields(
                 parametersDescriptionCollection: null,
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -525,6 +535,7 @@ public Task TestAddNewSpWithDifferentRestAndGraphQLOptions(
                 parametersDescriptionCollection: null,
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -571,6 +582,7 @@ public void TestAddStoredProcedureWithConflictingRestGraphQLOptions(
                 parametersDescriptionCollection: null,
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -620,6 +632,7 @@ public void TestAddEntityPermissionWithInvalidOperation(IEnumerable<string> perm
                 parametersDescriptionCollection: null,
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -695,6 +708,7 @@ public Task AddTableEntityWithMcpDmlTools(string mcpDmlTools, string source, str
                 parametersDescriptionCollection: null,
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -739,6 +753,7 @@ public Task AddStoredProcedureWithMcpCustomToolEnabled()
                 parametersDescriptionCollection: null,
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -780,6 +795,7 @@ public Task AddStoredProcedureWithBothMcpProperties()
                 parametersDescriptionCollection: null,
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -821,6 +837,7 @@ public Task AddStoredProcedureWithBothMcpPropertiesEnabled()
                 parametersDescriptionCollection: null,
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -862,6 +879,7 @@ public void AddTableEntityWithInvalidMcpCustomTool()
                 parametersDescriptionCollection: null,
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -910,6 +928,7 @@ public void AddEntityWithInvalidMcpOptions(string? mcpDmlTools, string? mcpCusto
                 parametersDescriptionCollection: null,
                 parametersRequiredCollection: null,
                 parametersDefaultCollection: null,
+                parametersAutoEmbedCollection: null,
                 fieldsNameCollection: [],
                 fieldsAliasCollection: [],
                 fieldsDescriptionCollection: [],
@@ -925,5 +944,72 @@ public void AddEntityWithInvalidMcpOptions(string? mcpDmlTools, string? mcpCusto
         }
 
         #endregion MCP Entity Configuration Tests
+
+        #region Auto-Embed CLI Tests
+
+        /// <summary>
+        /// Verify that --parameters.auto-embed correctly sets AutoEmbed on the resulting
+        /// ParameterMetadata, both with and without default values.
+        /// Per spec #3331, defaults are allowed on auto-embed parameters.
+        /// </summary>
+        [DataTestMethod]
+        [DataRow("query_text,top_k", "true,false", null, 0, true, null,
+            DisplayName = "auto-embed true/false on two params, no defaults")]
+        [DataRow("query_text", "true", "electronics", 0, true, "electronics",
+            DisplayName = "auto-embed with default value")]
+        public void AddEntityWithAutoEmbedParameter(
+            string paramNames,
+            string autoEmbedFlags,
+            string? defaultValues,
+            int assertIndex,
+            bool expectedAutoEmbed,
+            string? expectedDefault)
+        {
+            AddOptions options = new(
+                source: "dbo.SearchProducts",
+                permissions: new string[] { "anonymous", "execute" },
+                entity: "SearchProducts",
+                description: null,
+                sourceType: "stored-procedure",
+                sourceParameters: null,
+                sourceKeyFields: null,
+                restRoute: null,
+                graphQLType: null,
+                fieldsToInclude: Array.Empty<string>(),
+                fieldsToExclude: Array.Empty<string>(),
+                policyRequest: null,
+                policyDatabase: null,
+                cacheEnabled: null,
+                cacheTtlSeconds: null,
+                cacheLevel: null,
+                healthEnabled: null,
+                config: TEST_RUNTIME_CONFIG_FILE,
+                restMethodsForStoredProcedure: null,
+                graphQLOperationForStoredProcedure: null,
+                parametersNameCollection: paramNames.Split(','),
+                parametersDescriptionCollection: null,
+                parametersRequiredCollection: null,
+                parametersDefaultCollection: defaultValues?.Split(','),
+                parametersAutoEmbedCollection: autoEmbedFlags.Split(','),
+                fieldsNameCollection: [],
+                fieldsAliasCollection: [],
+                fieldsDescriptionCollection: [],
+                fieldsPrimaryKeyCollection: []
+            );
+
+            Assert.IsTrue(RuntimeConfigLoader.TryParseConfig(INITIAL_CONFIG, out RuntimeConfig? runtimeConfig));
+            Assert.IsTrue(TryAddNewEntity(options, runtimeConfig, out RuntimeConfig updatedConfig));
+
+            Entity entity = updatedConfig.Entities["SearchProducts"];
+            Assert.IsNotNull(entity.Source.Parameters);
+
+            ParameterMetadata param = entity.Source.Parameters[assertIndex];
+            Assert.AreEqual(expectedAutoEmbed, param.AutoEmbed,
+                $"Parameter '{param.Name}' AutoEmbed should be {expectedAutoEmbed}");
+            Assert.AreEqual(expectedDefault, param.Default,
+                $"Parameter '{param.Name}' Default should be '{expectedDefault}'");
+        }
+
+        #endregion Auto-Embed CLI Tests
     }
 }

src/Cli.Tests/Snapshots/AddEntityTests.AddNewEntityWhenEntitiesWithSourceAsStoredProcedure.verified.txt

@@ -33,17 +33,20 @@
             {
               Name: param1,
               Required: false,
-              Default: 123
+              Default: 123,
+              AutoEmbed: false
             },
             {
               Name: param2,
               Required: false,
-              Default: hello
+              Default: hello,
+              AutoEmbed: false
             },
             {
               Name: param3,
               Required: false,
-              Default: True
+              Default: True,
+              AutoEmbed: false
             }
           ]
         },