refine rule graph, add input/output schema, graph traversal switch, g…

src/Infrastructure/BotSharp.Abstraction/Rules/Constants/RuleConstant.cs

@@ -0,0 +1,32 @@
+namespace BotSharp.Abstraction.Rules.Constants;
+
+public static class RuleConstant
+{
+    public const int MAX_GRAPH_RECURSION = 1000;
+
+    public const string INPUT_SCHEMA_KEY = "input_schema";
+    public const string OUTPUT_SCHEMA_KEY = "output_schema";
+
+    public static IEnumerable<string> CONDITION_NODE_TYPES = new List<string>
+    {
+        "condition",
+        "criteria"
+    };
+
+    public static IEnumerable<string> ACTION_NODE_TYPES = new List<string>
+    {
+        "action"
+    };
+
+    public static IEnumerable<string> ROOT_NODE_TYPES = new List<string>
+    {
+        "root",
+        "start"
+    };
+
+    public static IEnumerable<string> END_NODE_TYPES = new List<string>
+    {
+        "end",
+        "terminal"
+    };
+}

src/Infrastructure/BotSharp.Abstraction/Rules/Frontier.cs

@@ -0,0 +1,66 @@
+namespace BotSharp.Core.Rules.Engines;
+
+/// <summary>
+/// Abstraction over the data structure that drives graph traversal order.
+/// Stack → DFS, Queue → BFS.  Swap the frontier mid-traversal to switch strategy.
+/// </summary>
+public interface IFrontier<T>
+{
+    void Add(T item);
+    T Remove();
+    int Count { get; }
+
+    /// <summary>
+    /// Drain every remaining item into <paramref name="other"/>, preserving order.
+    /// </summary>
+    void DrainTo(IFrontier<T> other);
+}
+
+/// <summary>
+/// LIFO frontier – produces depth-first traversal.
+/// </summary>
+public sealed class StackFrontier<T> : IFrontier<T>
+{
+    private readonly Stack<T> _stack = new();
+
+    public int Count => _stack.Count;
+
+    public void Add(T item) => _stack.Push(item);
+
+    public T Remove() => _stack.Pop();
+
+    public void DrainTo(IFrontier<T> other)
+    {
+        // Reverse so the item that was on top is added first and
+        // therefore ends up at the same "priority" position in the target.
+        var items = _stack.ToList();
+        items.Reverse();
+        _stack.Clear();
+        foreach (var item in items)
+        {
+            other.Add(item);
+        }
+    }
+}
+
+/// <summary>
+/// FIFO frontier – produces breadth-first traversal.
+/// </summary>
+public sealed class QueueFrontier<T> : IFrontier<T>
+{
+    private readonly Queue<T> _queue = new();
+
+    public int Count => _queue.Count;
+
+    public void Add(T item) => _queue.Enqueue(item);
+
+    public T Remove() => _queue.Dequeue();
+
+    public void DrainTo(IFrontier<T> other)
+    {
+        while (_queue.Count > 0)
+        {
+            other.Add(_queue.Dequeue());
+        }
+    }
+}

src/Infrastructure/BotSharp.Abstraction/Rules/IRuleEnd.cs

@@ -0,0 +1,5 @@
+namespace BotSharp.Abstraction.Rules;
+
+public interface IRuleEnd : IRuleFlowUnit
+{
+}

src/Infrastructure/BotSharp.Abstraction/Rules/IRuleFlowUnit.cs

@@ -18,4 +18,16 @@ public interface IRuleFlowUnit
     /// The trigger names
     /// </summary>
     IEnumerable<string>? Triggers => null;
+
+    /// <summary>
+    /// Schema describing the expected input parameters.
+    /// Used for validating that upstream nodes produce the required fields.
+    /// </summary>
+    FlowUnitSchema? InputSchema => null;
+
+    /// <summary>
+    /// Schema describing the output this unit produces.
+    /// Used for validating that downstream nodes receive the expected fields.
+    /// </summary>
+    FlowUnitSchema? OutputSchema => null;
 }

src/Infrastructure/BotSharp.Abstraction/Rules/IRuleRoot.cs

@@ -0,0 +1,5 @@
+namespace BotSharp.Abstraction.Rules;
+
+public interface IRuleRoot : IRuleFlowUnit
+{
+}

src/Infrastructure/BotSharp.Abstraction/Rules/Models/FlowUnitSchema.cs

@@ -0,0 +1,58 @@
+using System.Text.Json.Serialization;
+
+namespace BotSharp.Abstraction.Rules.Models;
+
+/// <summary>
+/// Describes the input or output contract of a rule flow unit (action or condition).
+/// Follows a JSON Schema-like structure with "properties" and "required" fields.
+/// </summary>
+public class FlowUnitSchema
+{
+    /// <summary>
+    /// Property definitions keyed by parameter name.
+    /// </summary>
+    [JsonPropertyName("properties")]
+    public Dictionary<string, FlowUnitSchemaProperty> Properties { get; set; } = [];
+
+    /// <summary>
+    /// List of required property names.
+    /// </summary>
+    [JsonPropertyName("required")]
+    public List<string> Required { get; set; } = [];
+
+    public FlowUnitSchema() { }
+
+    public FlowUnitSchema(
+        Dictionary<string, FlowUnitSchemaProperty> properties,
+        List<string>? required = null)
+    {
+        Properties = properties;
+        Required = required ?? [];
+    }
+}
+
+/// <summary>
+/// Describes a single property in a FlowUnitSchema.
+/// </summary>
+public class FlowUnitSchemaProperty
+{
+    /// <summary>
+    /// JSON type: "string", "number", "boolean", "object", "array"
+    /// </summary>
+    [JsonPropertyName("type")]
+    public string Type { get; set; } = "string";
+
+    /// <summary>
+    /// A brief explanation of the property's purpose.
+    /// </summary>
+    [JsonPropertyName("description")]
+    public string? Description { get; set; }
+
+    public FlowUnitSchemaProperty() { }
+
+    public FlowUnitSchemaProperty(string type, string? description = null)
+    {
+        Type = type;
+        Description = description;
+    }
+}

src/Infrastructure/BotSharp.Abstraction/Rules/Options/RuleFlowOptions.cs

@@ -20,6 +20,18 @@ public class RuleFlowOptions
     [JsonPropertyName("traversal_algorithm")]
     public string TraversalAlgorithm { get; set; } = "dfs";
 
+    /// <summary>
+    /// Whether to skip validation when loading the graph
+    /// </summary>
+    [JsonPropertyName("skip_validation")]
+    public bool SkipValidation { get; set; }
+
+    /// <summary>
+    /// Maximum number of nodes to visit
+    /// </summary>
+    [JsonPropertyName("max_recursion")]
+    public int? MaxRecursion { get; set; }
+
     /// <summary>
     /// Additional custom parameters, e.g., root_node_name, max_recursion
     /// </summary>

src/Infrastructure/BotSharp.Abstraction/Rules/RuleGraph.cs

@@ -1,3 +1,5 @@
+using BotSharp.Abstraction.Rules.Models;
+
 namespace BotSharp.Abstraction.Rules;
 
 public class RuleGraph
@@ -173,6 +175,20 @@ public class RuleNode : GraphItem
     /// </summary>
     public override string Type { get; set; } = "action";
 
+    /// <summary>
+    /// Input schema loaded from node config. Overrides the code-defined schema on IRuleFlowUnit.
+    /// </summary>
+    [JsonPropertyName("input_schema")]
+    [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+    public FlowUnitSchema? InputSchema { get; set; }
+
+    /// <summary>
+    /// Output schema loaded from node config. Overrides the code-defined schema on IRuleFlowUnit.
+    /// </summary>
+    [JsonPropertyName("output_schema")]
+    [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+    public FlowUnitSchema? OutputSchema { get; set; }
+
     public override string ToString()
     {
         return $"Node ({Id}): {Name} ({Type} => {Description})";

src/Infrastructure/BotSharp.Core.Rules/Actions/ChatAction.cs

@@ -1,6 +1,6 @@
 namespace BotSharp.Core.Rules.Actions;
 
-public sealed class ChatAction : IRuleAction
+public class ChatAction : IRuleAction
 {
     private readonly IServiceProvider _services;
     private readonly ILogger<ChatAction> _logger;
@@ -15,6 +15,17 @@ public ChatAction(
 
     public string Name => "send_message_to_agent";
 
+    public FlowUnitSchema? InputSchema => new();
+
+    public FlowUnitSchema? OutputSchema => new(
+        properties: new()
+        {
+            ["agent_id"] = new("string", "The agent ID"),
+            ["conversation_id"] = new("string", "The created conversation ID")
+        },
+        required: ["agent_id", "conversation_id"]
+    );
+
     public async Task<RuleNodeResult> ExecuteAsync(
         Agent agent,
         IRuleTrigger trigger,

src/Infrastructure/BotSharp.Core.Rules/Actions/HttpRequestAction.cs

@@ -4,7 +4,7 @@
 
 namespace BotSharp.Core.Rules.Actions;
 
-public sealed class HttpRequestAction : IRuleAction
+public class HttpRequestAction : IRuleAction
 {
     private readonly IServiceProvider _services;
     private readonly ILogger<HttpRequestAction> _logger;
@@ -22,11 +22,26 @@ public HttpRequestAction(
 
     public string Name => "http_request";
 
-    // Default configuration example:
-    // {
-    //     "http_url": "https://dummy.example.com/api/v1/employees",
-    //     "http_method": "GET"
-    // }
+    public FlowUnitSchema? InputSchema => new(
+        properties: new()
+        {
+            ["http_url"] = new("string", "The HTTP URL to request"),
+            ["http_method"] = new("string", "HTTP method: GET, POST, PUT, DELETE, PATCH"),
+            ["http_query_params"] = new("array", "Query parameters as key-value pairs"),
+            ["http_request_headers"] = new("array", "Request headers as key-value pairs"),
+            ["http_request_body"] = new("string", "Request body (JSON string)")
+        },
+        required: ["http_url", "http_method"]
+    );
+
+    public FlowUnitSchema? OutputSchema => new(
+        properties: new()
+        {
+            ["http_response"] = new("string", "The HTTP response body"),
+            ["http_response_headers"] = new("string", "The HTTP response headers as JSON")
+        },
+        required: ["http_response", "http_response_headers"]
+    );
 
     public async Task<RuleNodeResult> ExecuteAsync(
         Agent agent,

src/Infrastructure/BotSharp.Core.Rules/Actions/ToolCallAction.cs

@@ -2,7 +2,7 @@
 
 namespace BotSharp.Core.Rules.Actions;
 
-public sealed class ToolCallAction : IRuleAction
+public class ToolCallAction : IRuleAction
 {
     private readonly IServiceProvider _services;
     private readonly ILogger<ToolCallAction> _logger;
@@ -17,6 +17,25 @@ public ToolCallAction(
 
     public string Name => "tool_call";
 
+    public FlowUnitSchema? InputSchema => new(
+        properties: new()
+        {
+            ["function_name"] = new("string", "The name of the function to call"),
+            ["function_argument"] = new("object", "The function argument as a RoleDialogModel JSON")
+        },
+        required: ["function_name"]
+    );
+
+    public FlowUnitSchema? OutputSchema => new(
+        properties: new()
+        {
+            ["function_name"] = new("string", "The executed function name"),
+            ["function_argument"] = new("string", "The function argument as JSON string"),
+            ["function_call_result"] = new("string", "The function call result text")
+        },
+        required: ["function_name", "function_argument", "function_call_result"]
+    );
+
     public async Task<RuleNodeResult> ExecuteAsync(
         Agent agent,
         IRuleTrigger trigger,

src/Infrastructure/BotSharp.Core.Rules/Conditions/AllVisitedRuleCondition.cs

@@ -12,6 +12,10 @@ public AllVisitedRuleCondition(
 
     public string Name => "all_visited";
 
+    public FlowUnitSchema? InputSchema => new();
+
+    public FlowUnitSchema? OutputSchema => new();
+
     public async Task<RuleNodeResult> EvaluateAsync(
         Agent agent,
         IRuleTrigger trigger,