Add ask_agent: agent-to-agent delegation via the embedded MCP server

.github/workflows/ci.yml

@@ -48,7 +48,7 @@ jobs:
             group: e2e-shard-4
     name: e2e-${{ matrix.shard.name }}
     env:
-      MM_IMAGE: ${{ vars.MM_IMAGE || 'mattermostdevelopment/mattermost-enterprise-edition:release-11.9' }}
+      MM_IMAGE: ${{ vars.MM_IMAGE || 'mattermostdevelopment/mattermost-enterprise-edition:release-11.10' }}
     defaults:
       run:
         working-directory: ./e2e

api/api.go

@@ -21,6 +21,7 @@ import (
 	"github.com/mattermost/mattermost-plugin-agents/v2/conversation"
 	"github.com/mattermost/mattermost-plugin-agents/v2/conversations"
 	"github.com/mattermost/mattermost-plugin-agents/v2/customprompts"
+	"github.com/mattermost/mattermost-plugin-agents/v2/delegation"
 	"github.com/mattermost/mattermost-plugin-agents/v2/embeddings"
 	"github.com/mattermost/mattermost-plugin-agents/v2/enterprise"
 	"github.com/mattermost/mattermost-plugin-agents/v2/files"
@@ -162,6 +163,7 @@ type API struct {
 	streamStopNotifier    StreamStopClusterNotifier
 	conversationStore     ConversationStore
 	convService           *conversation.Service
+	delegationService     *delegation.Service
 	getSearchInitError    func() string
 	customPromptsStore    *customprompts.Store
 
@@ -297,6 +299,7 @@ func (a *API) ServeHTTP(c *plugin.Context, w http.ResponseWriter, r *http.Reques
 
 	router.GET("/conversations/:conversationid", a.handleGetConversation)
 	router.GET("/conversations/:conversationid/context", a.handleGetConversationContext)
+	router.GET("/delegations/:parenttoolcallid", a.handleGetDelegationStatus)
 
 	router.GET("/oauth/callback", a.handleOAuthCallback)
 	router.GET("/ai_threads", a.handleGetAIThreads)

api/api_delegation.go

@@ -0,0 +1,49 @@
+// Copyright (c) 2023-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package api
+
+import (
+	"errors"
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+	"github.com/mattermost/mattermost-plugin-agents/v2/delegation"
+)
+
+// SetDelegationService sets the delegation service used by the delegation
+// status endpoint.
+func (a *API) SetDelegationService(svc *delegation.Service) {
+	a.delegationService = svc
+}
+
+// handleGetDelegationStatus returns the live status of a delegation keyed by
+// the parent ask_agent tool call ID. Initiator-only: any other user (or an
+// unknown ID) gets a 404 so existence is not leaked.
+func (a *API) handleGetDelegationStatus(c *gin.Context) {
+	userID := c.GetHeader("Mattermost-User-Id")
+	parentToolCallID := c.Param("parenttoolcallid")
+
+	if a.delegationService == nil {
+		c.AbortWithStatus(http.StatusNotFound)
+		return
+	}
+
+	status, err := a.delegationService.StatusByParentToolCall(userID, parentToolCallID)
+	if err != nil {
+		if errors.Is(err, delegation.ErrNotConfigured) {
+			c.AbortWithStatus(http.StatusNotFound)
+			return
+		}
+		c.AbortWithError(http.StatusInternalServerError, err)
+		return
+	}
+	if status == nil {
+		// Expected for expired records, foreign users, and quick reconcile
+		// races — not an error worth logging.
+		c.AbortWithStatus(http.StatusNotFound)
+		return
+	}
+
+	c.JSON(http.StatusOK, status)
+}

api/api_no_tools_test.go

@@ -142,6 +142,10 @@ func (m *mockConvServiceStore) UpdateTurnContent(id string, content json.RawMess
 	return nil
 }
 
+func (m *mockConvServiceStore) UpdateTurnContentIfMatches(id string, expected, updated json.RawMessage) (bool, error) {
+	return true, nil
+}
+
 func (m *mockConvServiceStore) UpdateTurnTokens(_ string, _, _ int64) error {
 	return nil
 }

channels/analysis_conversation_test.go

@@ -105,6 +105,13 @@ func (s *inMemoryStore) UpdateTurnContent(id string, content json.RawMessage) er
 	return nil
 }
 
+func (s *inMemoryStore) UpdateTurnContentIfMatches(id string, _, updated json.RawMessage) (bool, error) {
+	if err := s.UpdateTurnContent(id, updated); err != nil {
+		return false, err
+	}
+	return true, nil
+}
+
 func (s *inMemoryStore) UpdateTurnTokens(id string, tokensIn, tokensOut int64) error {
 	turn, ok := s.turns[id]
 	if !ok {

channels/channels_eval_test.go

@@ -184,6 +184,10 @@ func (s *evalInMemoryStore) GetTurnsForConversation(conversationID string) ([]st
 	return turns, nil
 }
 
+func (s *evalInMemoryStore) UpdateTurnContentIfMatches(id string, _, updated json.RawMessage) (bool, error) {
+	return true, s.UpdateTurnContent(id, updated)
+}
+
 func (s *evalInMemoryStore) UpdateTurnContent(id string, content json.RawMessage) error {
 	if t, ok := s.turns[id]; ok {
 		t.Content = content

conversation/service.go

@@ -30,6 +30,7 @@ type Store interface {
 	GetTurnsForConversation(conversationID string) ([]store.Turn, error)
 	GetTurnByPostID(postID string) (*store.Turn, error)
 	UpdateTurnContent(id string, content json.RawMessage) error
+	UpdateTurnContentIfMatches(id string, expected, updated json.RawMessage) (bool, error)
 	UpdateTurnTokens(id string, tokensIn, tokensOut int64) error
 	UpdateTurnPostID(id string, postID *string) error
 	DeleteResponseTurns(conversationID, postID string) error
@@ -204,6 +205,14 @@ func (s *Service) UpdateTurnContent(turnID string, content json.RawMessage) erro
 	return s.store.UpdateTurnContent(turnID, content)
 }
 
+// ClaimTurnContent atomically replaces a turn's content only while it still
+// equals expected, returning whether this caller won the claim. Losing the
+// claim means another request (possibly on another node) already resolved the
+// same blocks.
+func (s *Service) ClaimTurnContent(turnID string, expected, updated json.RawMessage) (bool, error) {
+	return s.store.UpdateTurnContentIfMatches(turnID, expected, updated)
+}
+
 // CreateTurn persists a new turn in the store with an explicit sequence.
 func (s *Service) CreateTurn(turn *store.Turn) error {
 	return s.store.CreateTurn(turn)

conversations/conversations.go

@@ -35,18 +35,19 @@ type ConfigProvider interface {
 }
 
 type Conversations struct {
-	prompts           *llm.Prompts
-	mmClient          mmapi.Client
-	streamingService  streaming.Service
-	contextBuilder    *llmcontext.Builder
-	bots              *bots.MMBots
-	db                *mmapi.DBClient
-	licenseChecker    *enterprise.LicenseChecker
-	i18n              *i18n.Bundle
-	meetingsService   MeetingsService
-	configProvider    ConfigProvider
-	toolPolicyChecker mcp.ToolPolicyChecker
-	convService       *conversation.Service
+	prompts            *llm.Prompts
+	mmClient           mmapi.Client
+	streamingService   streaming.Service
+	contextBuilder     *llmcontext.Builder
+	bots               *bots.MMBots
+	db                 *mmapi.DBClient
+	licenseChecker     *enterprise.LicenseChecker
+	i18n               *i18n.Bundle
+	meetingsService    MeetingsService
+	configProvider     ConfigProvider
+	toolPolicyChecker  mcp.ToolPolicyChecker
+	convService        *conversation.Service
+	delegationNotifier DelegationNotifier
 }
 
 // MeetingsService defines the interface for meetings functionality needed by conversations