1 files changed, 20 insertions, 2 deletions
diff --git a/src/Agent.Core/Prompts/PromptComposer.cs b/src/Agent.Core/Prompts/PromptComposer.cs
index e07c7e8..69b18f3 100644
--- a/src/Agent.Core/Prompts/PromptComposer.cs
+++ b/src/Agent.Core/Prompts/PromptComposer.cs
@@ -1,5 +1,6 @@
 using Agent.Core.Ollama;
 using Agent.Core.Sessions;
+using Agent.Core.Skills;
 
 namespace Agent.Core.Prompts;
 
@@ -7,7 +8,8 @@ public sealed record PromptContext(
     string FixedSystemPrompt,
     string UserSystemPrompt,
     string Locale,
-    IReadOnlyList<string> Skills,
+    IReadOnlyList<AgentSkill> AvailableSkills,
+    IReadOnlyList<AgentSkill> SelectedSkills,
     string SandboxCapabilitySummary,
     string TaskGraphSummary,
     string PreviousSummary,
@@ -24,13 +26,29 @@ public static class PromptComposer
             new("system", context.FixedSystemPrompt),
             new("system", context.UserSystemPrompt),
             new("system", $"Respond in locale: {context.Locale}."),
-            new("system", string.Join("\n\n", context.Skills)),
+            new("system", ComposeSkillCatalog(context.AvailableSkills)),
             new("system", context.SandboxCapabilitySummary),
             new("system", context.TaskGraphSummary),
             new("system", context.PreviousSummary)
         };
+        // Inject selected skill instructions (Progressive Disclosure Stage 3).
+        foreach (AgentSkill skill in context.SelectedSkills)
+            messages.Add(new("system", skill.Instructions));
         messages.AddRange(context.Conversation.Select(static item => new OllamaMessage(item.Role, item.Content)));
         messages.Add(new OllamaMessage("user", context.Request, context.Images));
         return messages;
     }
+
+    /// <summary>
+    /// Stage 1 Discovery: only name + description are included. Full instructions are NOT included.
+    /// </summary>
+    private static string ComposeSkillCatalog(IReadOnlyList<AgentSkill> skills)
+    {
+        if (skills.Count == 0) return "No skills available.";
+        var lines = new List<string> { "Available skills:" };
+        foreach (AgentSkill skill in skills)
+            lines.Add($"- {skill.Name}: {skill.Description}");
+        lines.Add("If a skill is relevant to the request, indicate which skills to use.");
+        return string.Join("\n", lines);
+    }
 }