3 files changed, 56 insertions, 0 deletions
diff --git a/src/Agent.Core/Prompts/FixedPrompt.cs b/src/Agent.Core/Prompts/FixedPrompt.cs
new file mode 100644
index 0000000..6995bd4
--- /dev/null
+++ b/src/Agent.Core/Prompts/FixedPrompt.cs
@@ -0,0 +1,16 @@
+using System.Reflection;
+
+namespace Agent.Core.Prompts;
+
+public static class FixedPrompt
+{
+    private const string ResourceName = "Agent.Core.Prompts.FixedSystemPrompt.md";
+
+    public static string Load()
+    {
+        using Stream stream = typeof(FixedPrompt).Assembly.GetManifestResourceStream(ResourceName)
+            ?? throw new InvalidOperationException($"Embedded resource '{ResourceName}' was not found.");
+        using var reader = new StreamReader(stream);
+        return reader.ReadToEnd();
+    }
+}
diff --git a/src/Agent.Core/Prompts/FixedSystemPrompt.md b/src/Agent.Core/Prompts/FixedSystemPrompt.md
new file mode 100644
index 0000000..3cbc6e7
--- /dev/null
+++ b/src/Agent.Core/Prompts/FixedSystemPrompt.md
@@ -0,0 +1,4 @@
+You are the execution agent inside AI Agent Sandbox MCP Server.
+Follow the active SandboxPolicy and never claim an external effect unless an Internal Tool result proves it occurred.
+Never reveal hidden reasoning, policy internals, credentials, or capabilities not present in the supplied capability summary.
+Complete a request only when every TaskGraph node is completed and all required effects are verified.
diff --git a/src/Agent.Core/Prompts/PromptComposer.cs b/src/Agent.Core/Prompts/PromptComposer.cs
new file mode 100644
index 0000000..e07c7e8
--- /dev/null
+++ b/src/Agent.Core/Prompts/PromptComposer.cs
@@ -0,0 +1,36 @@
+using Agent.Core.Ollama;
+using Agent.Core.Sessions;
+
+namespace Agent.Core.Prompts;
+
+public sealed record PromptContext(
+    string FixedSystemPrompt,
+    string UserSystemPrompt,
+    string Locale,
+    IReadOnlyList<string> Skills,
+    string SandboxCapabilitySummary,
+    string TaskGraphSummary,
+    string PreviousSummary,
+    IReadOnlyList<ConversationMessage> Conversation,
+    string Request,
+    IReadOnlyList<string>? Images = null);
+
+public static class PromptComposer
+{
+    public static IReadOnlyList<OllamaMessage> Compose(PromptContext context)
+    {
+        var messages = new List<OllamaMessage>
+        {
+            new("system", context.FixedSystemPrompt),
+            new("system", context.UserSystemPrompt),
+            new("system", $"Respond in locale: {context.Locale}."),
+            new("system", string.Join("\n\n", context.Skills)),
+            new("system", context.SandboxCapabilitySummary),
+            new("system", context.TaskGraphSummary),
+            new("system", context.PreviousSummary)
+        };
+        messages.AddRange(context.Conversation.Select(static item => new OllamaMessage(item.Role, item.Content)));
+        messages.Add(new OllamaMessage("user", context.Request, context.Images));
+        return messages;
+    }
+}