Add researcher and general profiles with orchestrator delegation

packages/DBRepository/Sources/DBRepository/DBRepositoryMessaging.swift

@@ -141,6 +141,30 @@ public extension DBRepository {
         }
     }
 
+    func setMessagingThreadDefaultAgentProfile(threadID: String, handle: String?) throws {
+        let trimmedID = threadID.trimmingCharacters(in: .whitespacesAndNewlines)
+        guard !trimmedID.isEmpty else {
+            throw DBRepositoryError.sqliteOperationFailed("Messaging thread id is required.")
+        }
+        let normalized = handle?.trimmingCharacters(in: .whitespacesAndNewlines).lowercased()
+        let valueSQL: String
+        if let normalized, !normalized.isEmpty {
+            guard AgentProfileHandle.isValid(normalized) else {
+                throw DBRepositoryError.sqliteOperationFailed("Invalid agent profile handle.")
+            }
+            valueSQL = quoted(normalized)
+        } else {
+            valueSQL = "NULL"
+        }
+        try withDatabaseHandle { handle in
+            try Self.execute("""
+            UPDATE messaging_threads
+            SET default_agent_profile_handle = \(valueSQL)
+            WHERE id = \(quoted(trimmedID));
+            """, on: handle)
+        }
+    }
+
     func clearMessagingThreadUnread(id: String) throws {
         try withDatabaseHandle { handle in
             try Self.execute("""
@@ -339,7 +363,7 @@ public extension DBRepository {
         try Self.execute("""
         INSERT INTO messaging_threads (
             id, plugin_id, vendor_thread_id, title, last_activity_at,
-            muted, unread_count, created_at
+            muted, unread_count, default_agent_profile_handle, created_at
         ) VALUES (
             \(quoted(thread.id)),
             \(quoted(thread.pluginID)),
@@ -348,6 +372,7 @@ public extension DBRepository {
             \(quoted(activity)),
             \(thread.muted ? 1 : 0),
             \(max(0, thread.unreadCount)),
+            \(sqlValue(thread.defaultAgentProfileHandle)),
             \(quoted(created))
         )
         ON CONFLICT(plugin_id, vendor_thread_id) DO UPDATE SET
@@ -477,7 +502,7 @@ public extension DBRepository {
     private func loadMessagingThreads(pluginID: String, on handle: OpaquePointer) throws -> [MessagingThreadDTO] {
         let sql = """
         SELECT id, plugin_id, vendor_thread_id, title, last_activity_at,
-               muted, unread_count, created_at
+               muted, unread_count, created_at, default_agent_profile_handle
         FROM messaging_threads
         WHERE plugin_id = \(quoted(pluginID))
         ORDER BY last_activity_at DESC, id DESC;
@@ -497,7 +522,7 @@ public extension DBRepository {
     private func loadMessagingThread(id: String, on handle: OpaquePointer) throws -> MessagingThreadDTO? {
         let sql = """
         SELECT id, plugin_id, vendor_thread_id, title, last_activity_at,
-               muted, unread_count, created_at
+               muted, unread_count, created_at, default_agent_profile_handle
         FROM messaging_threads
         WHERE id = \(quoted(id))
         LIMIT 1;
@@ -518,7 +543,7 @@ public extension DBRepository {
     ) throws -> MessagingThreadDTO? {
         let sql = """
         SELECT id, plugin_id, vendor_thread_id, title, last_activity_at,
-               muted, unread_count, created_at
+               muted, unread_count, created_at, default_agent_profile_handle
         FROM messaging_threads
         WHERE plugin_id = \(quoted(pluginID))
           AND vendor_thread_id = \(quoted(vendorThreadID))
@@ -597,6 +622,7 @@ public extension DBRepository {
             lastActivityAt: Self.iso8601Formatter().date(from: try columnString(statement, index: 4)) ?? .now,
             muted: sqlite3_column_int(statement, 5) != 0,
             unreadCount: Int(sqlite3_column_int(statement, 6)),
+            defaultAgentProfileHandle: columnOptionalString(statement, index: 8),
             createdAt: Self.iso8601Formatter().date(from: try columnString(statement, index: 7)) ?? .now
         )
     }

packages/DBRepository/Sources/DBRepository/DatabaseSchema.swift

@@ -2,7 +2,7 @@ import Foundation
 import Structure
 
 public enum DatabaseSchema {
-    public static let latestVersion = 7
+    public static let latestVersion = 8
 
     public static func migrationSQL(version: Int, isUp: Bool) throws -> String {
         let migrationName = String(format: "%04d_%@", version, migrationFileBaseName(for: version))
@@ -37,6 +37,8 @@ public enum DatabaseSchema {
             return "agent_profiles"
         case 7:
             return "messaging_agent_handled"
+        case 8:
+            return "messaging_thread_default_profile"
         default:
             return "unknown"
         }

packages/DBRepository/Sources/DBRepository/Resources/Migrations/0008_messaging_thread_default_profile.down.sql

@@ -0,0 +1 @@
+ALTER TABLE messaging_threads DROP COLUMN default_agent_profile_handle;

packages/DBRepository/Sources/DBRepository/Resources/Migrations/0008_messaging_thread_default_profile.up.sql

@@ -0,0 +1 @@
+ALTER TABLE messaging_threads ADD COLUMN default_agent_profile_handle TEXT;

packages/DBRepository/Tests/DBRepositoryTests/DBMessagingTests.swift

@@ -330,6 +330,31 @@ final class DBMessagingTests: XCTestCase {
         XCTAssertEqual(Set(threads.map(\.vendorThreadID)), ["C1"])
     }
 
+    func testMessagingThreadDefaultAgentProfileRoundTrip() async throws {
+        let repository = try makeRepository()
+        _ = try await repository.createEmptyDatabaseIfNeeded(username: "app-user", password: "app-secret")
+        try await repository.upsertMessagingConnector(
+            MessagingConnectorDTO(pluginID: "slack-connection", displayName: "Slack")
+        )
+        let thread = MessagingThreadDTO(
+            pluginID: "slack-connection",
+            vendorThreadID: "C1",
+            title: "#general"
+        )
+        try await repository.upsertMessagingThread(thread)
+
+        try await repository.setMessagingThreadDefaultAgentProfile(
+            threadID: thread.id,
+            handle: AgentProfileHandle.researcher
+        )
+        let loaded = try await repository.messagingThread(id: thread.id)
+        XCTAssertEqual(loaded?.defaultAgentProfileHandle, AgentProfileHandle.researcher)
+
+        try await repository.setMessagingThreadDefaultAgentProfile(threadID: thread.id, handle: nil)
+        let cleared = try await repository.messagingThread(id: thread.id)
+        XCTAssertNil(cleared?.defaultAgentProfileHandle)
+    }
+
     private func makeRepository() throws -> DBRepository {
         let directory = FileManager.default.temporaryDirectory.appendingPathComponent(UUID().uuidString, isDirectory: true)
         try FileManager.default.createDirectory(at: directory, withIntermediateDirectories: true)

packages/DerrickBackend/Sources/DerrickBackend/MessagingAgentIngressRouter.swift

@@ -64,7 +64,12 @@ public enum MessagingAgentIngressRouter: Sendable {
             return nil
         }
 
-        guard let resolved = ConnectorMentionParser.resolvePrompt(body: body, botUserID: botUserID) else {
+        guard let resolved = ConnectorMentionParser.resolvePrompt(
+            body: body,
+            botUserID: botUserID,
+            channelDefaultProfileHandle: row.thread.defaultAgentProfileHandle,
+            profileCatalog: (try? await profileCatalog(repository: repository)) ?? []
+        ) else {
             return nil
         }
 
@@ -98,4 +103,10 @@ public enum MessagingAgentIngressRouter: Sendable {
         let authScheme = (derrick["auth_scheme"] as? String)?.trimmingCharacters(in: .whitespacesAndNewlines) ?? ""
         return role == "connector" && authScheme == "bot_token"
     }
+
+    private static func profileCatalog(repository: DBRepository) async throws -> [AgentProfileCatalogEntry] {
+        try await repository.listAgentProfiles()
+            .filter(\.isEnabled)
+            .map { AgentProfileCatalogEntry(handle: $0.handle, displayName: $0.displayName) }
+    }
 }

packages/MCPServer/Sources/MCPServer/Orchestration/AgentProfileDelegateToolModule.swift

@@ -0,0 +1,52 @@
+import Foundation
+import MCP
+import Structure
+
+/// Catalog module for `agent_profile_delegate`.
+public enum AgentProfileDelegateToolModule {
+    public static func makeRegistration(
+        handler: @escaping @Sendable (_ profileHandle: String, _ task: String) async throws -> String
+    ) -> MCPToolRegistration {
+        MCPToolRegistration(
+            tool: .agentProfileDelegate,
+            inputSchema: .object([
+                "type": .string("object"),
+                "properties": .object([
+                    "profile_handle": .object([
+                        "type": .string("string"),
+                        "description": .string(
+                            "Target profile handle without $: developer, researcher, or general."
+                        )
+                    ]),
+                    "task": .object([
+                        "type": .string("string"),
+                        "description": .string("Concrete task instructions for the delegated profile.")
+                    ])
+                ]),
+                "required": .array([.string("profile_handle"), .string("task")])
+            ])
+        ) { arguments in
+            let handle = stringArg(arguments, "profile_handle") ?? ""
+            let task = stringArg(arguments, "task") ?? ""
+            guard !handle.isEmpty, !task.isEmpty else {
+                throw NSError(
+                    domain: "AgentProfileDelegate",
+                    code: 400,
+                    userInfo: [NSLocalizedDescriptionKey: "profile_handle and task are required"]
+                )
+            }
+            return try await handler(handle, task)
+        }
+    }
+
+    private static func stringArg(_ arguments: [String: Value], _ key: String) -> String? {
+        guard let value = arguments[key] else { return nil }
+        switch value {
+        case .string(let s): return s
+        case .int(let i): return String(i)
+        case .double(let d): return String(d)
+        case .bool(let b): return b ? "true" : "false"
+        default: return nil
+        }
+    }
+}

packages/Structure/Sources/AgentRuntime/AgentProfile.swift

@@ -24,8 +24,13 @@ public struct AgentProfileRAGConfig: Codable, Sendable, Hashable {
 public enum AgentProfileHandle {
     public static let orchestrator = "orchestrator"
     public static let developer = "developer"
+    public static let researcher = "researcher"
+    public static let general = "general"
 
-    public static let allBuiltins = [orchestrator, developer]
+    public static let allBuiltins = [orchestrator, developer, researcher, general]
+
+    /// Profiles the orchestrator may delegate to via `agent_profile_delegate`.
+    public static let delegateTargets = [developer, researcher, general]
 
     public static func normalize(_ raw: String) -> String? {
         let trimmed = raw.trimmingCharacters(in: .whitespacesAndNewlines).lowercased()
@@ -114,30 +119,37 @@ public struct AgentProfile: Codable, Sendable, Hashable, Identifiable {
         rag.useSessionMemory ? rag.retrievalLimit : 0
     }
 
-    public static func orchestratorDefault(modelJSON: Data) -> AgentProfile {
+    public static func orchestratorDefault(modelJSON: Data, thinkingJSON: Data? = nil) -> AgentProfile {
         AgentProfile(
             id: "builtin-orchestrator",
             displayName: "Orchestrator",
             handle: AgentProfileHandle.orchestrator,
             instructions: """
-            You are Derrick's orchestrator — the default generalist profile.
+            You are Derrick's orchestrator — a router-first generalist.
+
+            Understand what the user wants. You may research or clarify yourself before routing. \
+            Handle simple requests directly when delegation is unnecessary.
 
-            Your job is to understand what the user wants, break work into clear steps, and \
-            coordinate execution. For implementation, debugging, code review, or technical changes, \
-            prefer delegating to the Developer profile ($developer). Summarize outcomes for the \
-            user in plain language and report blockers early.
+            When another profile fits better, delegate with `agent_profile_delegate`:
+            - `developer` — code, debugging, implementation, technical execution
+            - `researcher` — research, summarization, synthesis from sources
+            - `general` — everyday workhorse tasks when no specialist fits
+
+            Use `general` when unsure which specialist fits. Summarize delegated outcomes in plain \
+            language and report blockers early.
 
             Stay concise unless the user asks for detail.
             """,
             modelJSON: modelJSON,
+            thinkingJSON: thinkingJSON,
             rag: .default,
             isEnabled: true,
             isBuiltin: true,
             sortOrder: 0
         )
     }
 
-    public static func developerDefault(modelJSON: Data) -> AgentProfile {
+    public static func developerDefault(modelJSON: Data, thinkingJSON: Data? = nil) -> AgentProfile {
         AgentProfile(
             id: "builtin-developer",
             displayName: "Developer",
@@ -150,17 +162,61 @@ public struct AgentProfile: Codable, Sendable, Hashable, Identifiable {
             When scope is unclear, ask one focused clarifying question before diving in.
             """,
             modelJSON: modelJSON,
+            thinkingJSON: thinkingJSON,
             rag: .default,
             isEnabled: true,
             isBuiltin: true,
             sortOrder: 1
         )
     }
 
-    public static func builtinProfiles(modelJSON: Data) -> [AgentProfile] {
+    public static func researcherDefault(modelJSON: Data, thinkingJSON: Data? = nil) -> AgentProfile {
+        AgentProfile(
+            id: "builtin-researcher",
+            displayName: "Researcher",
+            handle: AgentProfileHandle.researcher,
+            instructions: """
+            You are Derrick's Researcher profile. Find, read, and synthesize information. Summarize \
+            clearly with sources when available. Prefer accurate synthesis over speculation.
+
+            When research is incomplete, say what is known, what is uncertain, and what would help next.
+            """,
+            modelJSON: modelJSON,
+            thinkingJSON: thinkingJSON,
+            rag: .default,
+            isEnabled: true,
+            isBuiltin: true,
+            sortOrder: 2
+        )
+    }
+
+    public static func generalDefault(modelJSON: Data, thinkingJSON: Data? = nil) -> AgentProfile {
+        AgentProfile(
+            id: "builtin-general",
+            displayName: "General",
+            handle: AgentProfileHandle.general,
+            instructions: """
+            You are Derrick's General profile — the workhorse for everyday tasks: writing, planning, \
+            brainstorming, mixed requests, and anything that does not need a specialist. Be practical, \
+            direct, and helpful.
+
+            When scope is unclear, ask one focused clarifying question before proceeding.
+            """,
+            modelJSON: modelJSON,
+            thinkingJSON: thinkingJSON,
+            rag: .default,
+            isEnabled: true,
+            isBuiltin: true,
+            sortOrder: 3
+        )
+    }
+
+    public static func builtinProfiles(modelJSON: Data, thinkingJSON: Data? = nil) -> [AgentProfile] {
         [
-            orchestratorDefault(modelJSON: modelJSON),
-            developerDefault(modelJSON: modelJSON),
+            orchestratorDefault(modelJSON: modelJSON, thinkingJSON: thinkingJSON),
+            developerDefault(modelJSON: modelJSON, thinkingJSON: thinkingJSON),
+            researcherDefault(modelJSON: modelJSON, thinkingJSON: thinkingJSON),
+            generalDefault(modelJSON: modelJSON, thinkingJSON: thinkingJSON),
         ]
     }
 }

packages/Structure/Sources/AppLayerServices/AppServices/MessagingDTOs.swift

@@ -38,6 +38,8 @@ public struct MessagingThreadDTO: Codable, Sendable, Hashable, Identifiable {
     public var lastActivityAt: Date
     public var muted: Bool
     public var unreadCount: Int
+    /// When set, inbound @Derrick messages without `$handle` use this profile instead of orchestrator.
+    public var defaultAgentProfileHandle: String?
     public let createdAt: Date
 
     public init(
@@ -48,6 +50,7 @@ public struct MessagingThreadDTO: Codable, Sendable, Hashable, Identifiable {
         lastActivityAt: Date = .now,
         muted: Bool = false,
         unreadCount: Int = 0,
+        defaultAgentProfileHandle: String? = nil,
         createdAt: Date = .now
     ) {
         self.id = id
@@ -57,6 +60,7 @@ public struct MessagingThreadDTO: Codable, Sendable, Hashable, Identifiable {
         self.lastActivityAt = lastActivityAt
         self.muted = muted
         self.unreadCount = unreadCount
+        self.defaultAgentProfileHandle = defaultAgentProfileHandle
         self.createdAt = createdAt
     }
 }

packages/Structure/Sources/MCPToolCatalog/AllowedMCPTool.swift

@@ -12,6 +12,8 @@ public enum AllowedMCPTool: String, CaseIterable, Sendable, Codable, Hashable {
     case agentsList = "agents_list"
     case agentsSend = "agents_send"
     case agentsCancel = "agents_cancel"
+    /// Orchestrator delegates a sub-task to another agent profile ($developer, $researcher, $general).
+    case agentProfileDelegate = "agent_profile_delegate"
     /// One-shot durable job (optional delay). Local orchestration → JobService.
     case jobsCreate = "jobs_create"
     /// Recurring or one-shot schedule template. Local orchestration → JobService.
@@ -54,6 +56,8 @@ public enum AllowedMCPTool: String, CaseIterable, Sendable, Codable, Hashable {
             return "Send a message to a parent or child agent only (no peer messaging)."
         case .agentsCancel:
             return "Cancel a child agent (or self) in the current session."
+        case .agentProfileDelegate:
+            return "Delegate a task to another agent profile (developer, researcher, or general) and return its result."
         case .jobsCreate:
             return "Create a one-shot background job (optional delay). Freezes a tool call; optional wake of this agent after the tool runs."
         case .jobsScheduleCreate: