Rich tool call rendering: readable arguments and responses, post previews, path-identical metadata

conversation/content_block.go

@@ -50,6 +50,13 @@ type ContentBlock struct {
 	Status       string          `json:"status,omitempty"`
 	Shared       *bool           `json:"shared,omitempty"` // pointer to distinguish unset from false
 
+	// Title and Description mirror llm.ToolCall so a reloaded conversation
+	// renders the same tool identity the live websocket event showed. Both
+	// are visible to non-requesters like Name. Description is not rendered
+	// anywhere yet.
+	Title       string `json:"title,omitempty"`
+	Description string `json:"description,omitempty"`
+
 	// UserInteraction is the persisted form of llm.Tool.UserInteraction.
 	UserInteraction string `json:"user_interaction,omitempty"`
 
@@ -104,11 +111,11 @@ func BoolPtr(b bool) *bool { return &b }
 func Int64Ptr(v int64) *int64 { return &v }
 
 // FilterForNonRequester returns a new slice of content blocks with private
-// tool data redacted. Tool use blocks with shared != true have their Input
-// field set to nil. Tool result blocks with shared != true have their Content
-// field set to empty string. All other block types pass through unchanged.
-// The original slice and its elements are never mutated.
-// Returns nil if the input is nil.
+// tool data redacted. Tool use blocks with shared != true have Input and
+// MCPBareName cleared; tool result blocks with shared != true have Content
+// cleared. Tool identity (Name, Title, Description, ServerOrigin) stays
+// visible, mirroring redactToolCalls on the live path so both paths render
+// identically. The original slice is never mutated; nil in, nil out.
 func FilterForNonRequester(blocks []ContentBlock) []ContentBlock {
 	if blocks == nil {
 		return nil
@@ -133,10 +140,11 @@ func FilterForNonRequester(blocks []ContentBlock) []ContentBlock {
 }
 
 // SanitizeForDisplay returns a new slice of content blocks with LLM-generated
-// string fields sanitized against Unicode bidi/spoofing attacks. Tool use
-// blocks have their Input field sanitized, and tool result blocks have their
-// Content field sanitized. The original slice is never mutated.
-// Returns nil if the input is nil.
+// and MCP-server-supplied string fields sanitized against Unicode bidi/spoofing
+// attacks: Input, Title, and Description on tool_use blocks, Content on
+// tool_result blocks. Title/Description are already sanitized at capture; this
+// is defense in depth that also covers older persisted turns. The original
+// slice is never mutated; nil in, nil out.
 func SanitizeForDisplay(blocks []ContentBlock) []ContentBlock {
 	if blocks == nil {
 		return nil
@@ -150,6 +158,12 @@ func SanitizeForDisplay(blocks []ContentBlock) []ContentBlock {
 			if len(block.Input) > 0 {
 				result[i].Input = json.RawMessage(llm.SanitizeNonPrintableChars(string(block.Input)))
 			}
+			if block.Title != "" {
+				result[i].Title = llm.SanitizeNonPrintableChars(block.Title)
+			}
+			if block.Description != "" {
+				result[i].Description = llm.SanitizeNonPrintableChars(block.Description)
+			}
 		case BlockTypeToolResult:
 			if block.Content != "" {
 				result[i].Content = llm.SanitizeNonPrintableChars(block.Content)

conversation/content_block_test.go

@@ -110,6 +110,22 @@ func TestContentBlockMarshalUnmarshal(t *testing.T) {
 			},
 			expected: `{"type":"tool_use","id":"tc_02","name":"read_file","input":{"path":"/etc/passwd"},"status":"pending","shared":false}`,
 		},
+		{
+			name: "tool_use block with title/description/mcp_bare_name",
+			block: ContentBlock{
+				Type:         BlockTypeToolUse,
+				ID:           "tc_03",
+				Name:         "mattermost__create_post",
+				ServerOrigin: "embedded://mattermost",
+				MCPBareName:  "create_post",
+				Title:        "Create Post",
+				Description:  "Create a new post in Mattermost.",
+				Input:        json.RawMessage(`{"channel_id":"c1"}`),
+				Status:       StatusPending,
+				Shared:       BoolPtr(true),
+			},
+			expected: `{"type":"tool_use","id":"tc_03","name":"mattermost__create_post","server_origin":"embedded://mattermost","input":{"channel_id":"c1"},"mcp_bare_name":"create_post","status":"pending","shared":true,"title":"Create Post","description":"Create a new post in Mattermost."}`,
+		},
 	}
 
 	for _, tt := range tests {
@@ -194,6 +210,8 @@ func TestFilterForNonRequesterRedactsApprovalMetadata(t *testing.T) {
 		Type:        BlockTypeToolUse,
 		ID:          "tc_private",
 		Name:        "jira__get_issue",
+		Title:       "Get Issue",
+		Description: "Get a Jira issue",
 		Input:       json.RawMessage(`{"key":"MM-1"}`),
 		MCPBareName: "get_issue",
 		Status:      StatusPending,
@@ -205,6 +223,10 @@ func TestFilterForNonRequesterRedactsApprovalMetadata(t *testing.T) {
 	require.Len(t, result, 1)
 	assert.Nil(t, result[0].Input)
 	assert.Empty(t, result[0].MCPBareName)
+	// Tool identity stays visible to non-requesters, matching redactToolCalls.
+	assert.Equal(t, "Get Issue", result[0].Title)
+	assert.Equal(t, "Get a Jira issue", result[0].Description)
+	assert.Equal(t, "jira__get_issue", result[0].Name)
 	assert.NotNil(t, blocks[0].Input, "original block must not be mutated")
 	assert.Equal(t, "get_issue", blocks[0].MCPBareName, "original block must not be mutated")
 }
@@ -331,3 +353,43 @@ func TestFilterForNonRequesterDoesNotMutateOriginal(t *testing.T) {
 	assert.Equal(t, originalInputCopy, original[0].Input)
 	assert.Equal(t, originalContentCopy, original[1].Content)
 }
+
+func TestSanitizeForDisplaySanitizesTitleAndDescription(t *testing.T) {
+	// U+202E (right-to-left override) is a classic bidi spoofing character.
+	blocks := []ContentBlock{{
+		Type:        BlockTypeToolUse,
+		ID:          "tc1",
+		Name:        "jira__get_issue",
+		Title:       "Get\u202eIssue",
+		Description: "Get\u202ean issue",
+		Input:       json.RawMessage("{\"key\":\"MM\u202e-1\"}"),
+		Status:      StatusPending,
+	}}
+
+	result := SanitizeForDisplay(blocks)
+
+	require.Len(t, result, 1)
+	assert.Equal(t, "Get[U+202E]Issue", result[0].Title)
+	assert.Equal(t, "Get[U+202E]an issue", result[0].Description)
+	assert.Contains(t, string(result[0].Input), "[U+202E]")
+
+	// Original is not mutated.
+	assert.Equal(t, "Get\u202eIssue", blocks[0].Title)
+	assert.Equal(t, "Get\u202ean issue", blocks[0].Description)
+}
+
+func TestSanitizeForDisplayLeavesCleanTitleAndDescription(t *testing.T) {
+	blocks := []ContentBlock{{
+		Type:        BlockTypeToolUse,
+		ID:          "tc1",
+		Name:        "jira__get_issue",
+		Title:       "Get Issue",
+		Description: "Get a Jira issue",
+	}}
+
+	result := SanitizeForDisplay(blocks)
+
+	require.Len(t, result, 1)
+	assert.Equal(t, "Get Issue", result[0].Title)
+	assert.Equal(t, "Get a Jira issue", result[0].Description)
+}

conversation/convert.go

@@ -87,6 +87,8 @@ func BlocksToPost(
 				Arguments:    arguments,
 				MCPBareName:  block.MCPBareName,
 				Status:       StatusFromString(block.Status),
+				Title:        block.Title,
+				Description:  block.Description,
 			}
 			if redactToolUse {
 				toolCall.MCPBareName = ""
@@ -268,6 +270,8 @@ func PostToBlocks(post llm.Post, shared bool) []ContentBlock {
 			MCPBareName:  tc.MCPBareName,
 			Status:       StatusToString(tc.Status),
 			Shared:       BoolPtr(shared),
+			Title:        tc.Title,
+			Description:  tc.Description,
 		})
 
 		if tc.Result != "" {

conversation/convert_test.go

@@ -231,7 +231,6 @@ func TestBlocksToPost_RedactUnshared(t *testing.T) {
 		assert.JSONEq(t, `{}`, args["t-nilshared"])
 		for _, tc := range got.ToolUse {
 			if tc.ID == "t-private" {
-				assert.Nil(t, tc.Schema)
 				assert.Empty(t, tc.MCPBareName)
 				assert.Empty(t, tc.Description)
 			}
@@ -246,16 +245,11 @@ func TestPostToBlocksPreservesToolIdentityMetadata(t *testing.T) {
 			ID:           "tc1",
 			Name:         "jira__get_issue",
 			Description:  "Get a Jira issue",
+			Title:        "Get Issue",
 			ServerOrigin: "https://jira.example.com",
 			Arguments:    json.RawMessage(`{"key":"MM-1"}`),
-			Schema: map[string]any{
-				"type": "object",
-				"properties": map[string]any{
-					"key": map[string]any{"type": "string"},
-				},
-			},
-			MCPBareName: "get_issue",
-			Status:      llm.ToolCallStatusPending,
+			MCPBareName:  "get_issue",
+			Status:       llm.ToolCallStatusPending,
 		}},
 	}
 
@@ -266,11 +260,13 @@ func TestPostToBlocksPreservesToolIdentityMetadata(t *testing.T) {
 	assert.Equal(t, "jira__get_issue", blocks[0].Name)
 	assert.Equal(t, "https://jira.example.com", blocks[0].ServerOrigin)
 	assert.Equal(t, "get_issue", blocks[0].MCPBareName)
+	assert.Equal(t, "Get Issue", blocks[0].Title)
+	assert.Equal(t, "Get a Jira issue", blocks[0].Description)
 
 	data, err := json.Marshal(blocks[0])
 	require.NoError(t, err)
 	assert.NotContains(t, string(data), "input_schema")
-	assert.NotContains(t, string(data), "tool_description")
+	assert.NotContains(t, string(data), "\"schema\"")
 }
 
 func TestBlocksToPostRehydratesToolCatalogMetadata(t *testing.T) {
@@ -290,6 +286,7 @@ func TestBlocksToPostRehydratesToolCatalogMetadata(t *testing.T) {
 	toolStore.AddTools([]llm.Tool{{
 		Name:         "jira__get_issue",
 		Description:  "Get a Jira issue",
+		Title:        "Get Issue",
 		Schema:       schema,
 		ServerOrigin: "https://jira.example.com",
 	}})
@@ -303,8 +300,7 @@ func TestBlocksToPostRehydratesToolCatalogMetadata(t *testing.T) {
 	assert.Equal(t, "https://jira.example.com", toolCall.ServerOrigin)
 	assert.Equal(t, "get_issue", toolCall.MCPBareName)
 	assert.Equal(t, "Get a Jira issue", toolCall.Description)
-	require.IsType(t, json.RawMessage{}, toolCall.Schema)
-	assert.JSONEq(t, `{"type":"object","properties":{"key":{"type":"string"}}}`, string(toolCall.Schema.(json.RawMessage)))
+	assert.Equal(t, "Get Issue", toolCall.Title)
 }
 
 func TestPostToBlocks(t *testing.T) {

conversation/helpers.go

@@ -112,6 +112,8 @@ func toolUseBlocks(
 			Status:          StatusToString(tc.Status),
 			Shared:          BoolPtr(shared),
 			UserInteraction: tc.UserInteraction,
+			Title:           tc.Title,
+			Description:     tc.Description,
 		})
 	}
 

conversation/helpers_test.go

@@ -65,9 +65,9 @@ func TestToolUseBlocksPreservesApprovalMetadata(t *testing.T) {
 		ID:           "tc1",
 		Name:         "jira__get_issue",
 		Description:  "Get a Jira issue",
+		Title:        "Get Issue",
 		ServerOrigin: "https://jira.example.com",
 		Arguments:    json.RawMessage(`{"key":"MM-1"}`),
-		Schema:       json.RawMessage(`{"type":"object"}`),
 		MCPBareName:  "get_issue",
 		Status:       llm.ToolCallStatusPending,
 	}}, false)
@@ -77,6 +77,8 @@ func TestToolUseBlocksPreservesApprovalMetadata(t *testing.T) {
 	assert.Equal(t, "jira__get_issue", blocks[0].Name)
 	assert.Equal(t, "https://jira.example.com", blocks[0].ServerOrigin)
 	assert.Equal(t, "get_issue", blocks[0].MCPBareName)
+	assert.Equal(t, "Get Issue", blocks[0].Title)
+	assert.Equal(t, "Get a Jira issue", blocks[0].Description)
 }
 
 func TestUnmarshalBlocks(t *testing.T) {

conversation/tool_use_writer_parity_test.go

@@ -0,0 +1,87 @@
+// Copyright (c) 2023-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package conversation
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/mattermost/mattermost-plugin-agents/v2/llm"
+	"github.com/stretchr/testify/require"
+)
+
+// persistedToolUseFields are the tool_use ContentBlock JSON tags the writers
+// in this package must emit so a tool call renders identically live and after
+// reload. Keep in sync with the persisted fields in
+// streaming/tool_call_parity_test.go, which covers the live-path writer and
+// redaction parity but cannot reach the unexported toolUseBlocks.
+var persistedToolUseFields = []string{
+	"id",
+	"name",
+	"server_origin",
+	"input",
+	"mcp_bare_name",
+	"status",
+	"title",
+	"description",
+	"user_interaction",
+}
+
+func parityToolCall() llm.ToolCall {
+	return llm.ToolCall{
+		ID:              "tc-1",
+		Name:            "mattermost__create_post",
+		Description:     "Create a post",
+		Title:           "Create Post",
+		Arguments:       json.RawMessage(`{"channel_id":"c1"}`),
+		Status:          llm.ToolCallStatusSuccess,
+		MCPBareName:     "create_post",
+		UserInteraction: llm.UserInteractionSelect,
+		ServerOrigin:    "embedded://mattermost",
+	}
+}
+
+func toolUseBlockJSONMap(t *testing.T, block ContentBlock) map[string]any {
+	t.Helper()
+	data, err := json.Marshal(block)
+	require.NoError(t, err)
+	var m map[string]any
+	require.NoError(t, json.Unmarshal(data, &m))
+	return m
+}
+
+// TestToolUseBlocksPersistsPolicyFields asserts the auto-run writer
+// (toolUseBlocks) emits every persisted tool_use identity/metadata field for a
+// fully-populated call, so an auto-run round renders the same as a live one.
+func TestToolUseBlocksPersistsPolicyFields(t *testing.T) {
+	blocks := toolUseBlocks("", llm.ReasoningData{}, []llm.ToolCall{parityToolCall()}, true)
+	require.Len(t, blocks, 1)
+	require.Equal(t, BlockTypeToolUse, blocks[0].Type)
+
+	m := toolUseBlockJSONMap(t, blocks[0])
+	for _, field := range persistedToolUseFields {
+		require.Containsf(t, m, field, "toolUseBlocks dropped persisted tool_use field %q", field)
+		require.NotEmptyf(t, m[field], "toolUseBlocks emitted an empty persisted tool_use field %q", field)
+	}
+}
+
+// TestPostToBlocksPersistsPolicyFields asserts the generic Post->blocks
+// converter carries the same tool identity/metadata. It intentionally omits
+// user_interaction: PostToBlocks converts completed posts, where the pending
+// interaction kind is not meaningful (it is set by the approval-path writers).
+func TestPostToBlocksPersistsPolicyFields(t *testing.T) {
+	post := llm.Post{Role: llm.PostRoleBot, ToolUse: []llm.ToolCall{parityToolCall()}}
+	blocks := PostToBlocks(post, true)
+	require.GreaterOrEqual(t, len(blocks), 1)
+	require.Equal(t, BlockTypeToolUse, blocks[0].Type)
+
+	m := toolUseBlockJSONMap(t, blocks[0])
+	for _, field := range persistedToolUseFields {
+		if field == "user_interaction" {
+			continue
+		}
+		require.Containsf(t, m, field, "PostToBlocks dropped persisted tool_use field %q", field)
+		require.NotEmptyf(t, m[field], "PostToBlocks emitted an empty persisted tool_use field %q", field)
+	}
+}

e2e/scripts/ci-test-groups.mjs

@@ -20,6 +20,7 @@ const groups = {
         'tests/rhs-core/new-messages-rhs.spec.ts',
         'tests/tool-config/policy-change.spec.ts',
         'tests/tool-config/tab-layout.spec.ts',
+        'tests/tool-config/mock-api/rich-create-post-card.spec.ts',
         'tests/custom-prompts/custom-prompts.spec.ts',
         'tests/meeting-summary/summary-persistence.spec.ts',
         'tests/channel-analysis/backend-verification/real-api.spec.ts',