feat: publish v1.0.0-rc.36-custom.1

relaykit/relayconvert/internal/toolconv/response_artifacts.go

@@ -0,0 +1,816 @@
+package toolconv
+
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+
+	"github.com/QuantumNous/new-api/relaykit/dto"
+	"github.com/QuantumNous/new-api/relaykit/relayconvert/convmeta"
+	geminichat "github.com/QuantumNous/new-api/relaykit/relayconvert/internal/gemini_chat"
+	kitutil "github.com/QuantumNous/new-api/relaykit/relayconvert/kitutil"
+	"github.com/QuantumNous/new-api/relaykit/types"
+)
+
+type HostedResponseItem struct {
+	Kind              Kind
+	NativeType        string
+	ID                string
+	CallID            string
+	Name              string
+	Status            string
+	Position          int
+	Action            json.RawMessage
+	Results           json.RawMessage
+	Sources           json.RawMessage
+	Caller            json.RawMessage
+	Arguments         json.RawMessage
+	Output            json.RawMessage
+	Error             json.RawMessage
+	ServerName        string
+	IsError           *bool
+	ApprovalRequestID string
+	Tools             json.RawMessage
+	ErrorCode         string
+	Raw               json.RawMessage
+}
+
+type HostedResponseSet struct {
+	Source           types.RelayFormat
+	Items            []HostedResponseItem
+	SourceLength     int
+	RegularPositions []int
+}
+
+type positionedResponsesOutput struct {
+	position int
+	output   dto.ResponsesOutput
+}
+
+type positionedClaudeBlocks struct {
+	position int
+	blocks   []dto.ClaudeMediaMessage
+}
+
+func (s HostedResponseSet) Empty() bool {
+	return len(s.Items) == 0
+}
+
+// ExtractHostedResponse removes server-executed tool artifacts before a
+// message converter sees them. The artifacts travel beside multi-step routes,
+// just like request tool definitions, so a lossy Chat pivot cannot reclassify
+// or discard them.
+func ExtractHostedResponse(format types.RelayFormat, response any) (any, HostedResponseSet, error) {
+	switch format {
+	case types.RelayFormatClaude:
+		return extractClaudeHostedResponse(response)
+	case types.RelayFormatOpenAIResponses:
+		return extractOpenAIHostedResponse(response)
+	case types.RelayFormatGemini:
+		return extractGeminiHostedResponse(response)
+	default:
+		return response, HostedResponseSet{Source: format}, nil
+	}
+}
+
+func AttachHostedResponse(format types.RelayFormat, response any, set HostedResponseSet, options *convmeta.Options) (any, []types.ConversionDiagnostic, error) {
+	if set.Empty() {
+		return response, nil, nil
+	}
+	var (
+		value       any
+		diagnostics []types.ConversionDiagnostic
+		err         error
+	)
+	switch format {
+	case types.RelayFormatOpenAIResponses:
+		value, diagnostics, err = attachOpenAIHostedResponse(response, set)
+	case types.RelayFormatClaude:
+		value, diagnostics, err = attachClaudeHostedResponse(response, set)
+	default:
+		value = response
+		for index, item := range set.Items {
+			diagnostics = append(diagnostics, responsePresentationLoss(
+				fmt.Sprintf("hosted_tools[%d]", index),
+				"hosted_tool_event_omitted",
+				fmt.Sprintf("%s cannot represent hosted-tool response %q", format, item.NativeType),
+			))
+		}
+	}
+	if err != nil {
+		return nil, diagnostics, err
+	}
+	for index := range diagnostics {
+		diagnostics[index].From = set.Source
+		diagnostics[index].To = format
+	}
+	return value, diagnostics, nil
+}
+
+func extractClaudeHostedResponse(response any) (any, HostedResponseSet, error) {
+	var source *dto.ClaudeResponse
+	switch value := response.(type) {
+	case *dto.ClaudeResponse:
+		source = value
+	case dto.ClaudeResponse:
+		source = &value
+	default:
+		return nil, HostedResponseSet{}, fmt.Errorf("expected Claude response, got %T", response)
+	}
+	clone := *source
+	clone.Content = make([]dto.ClaudeMediaMessage, 0, len(source.Content))
+	set := HostedResponseSet{Source: types.RelayFormatClaude, SourceLength: len(source.Content)}
+	for position := range source.Content {
+		block := source.Content[position]
+		blockType := strings.TrimSpace(block.Type)
+		switch {
+		case blockType == "server_tool_use" || blockType == "mcp_tool_use":
+			rawBlock, err := kitutil.Marshal(block)
+			if err != nil {
+				return nil, set, fmt.Errorf("content[%d]: %w", position, err)
+			}
+			action, err := kitutil.Marshal(block.Input)
+			if err != nil {
+				return nil, set, fmt.Errorf("content[%d].input: %w", position, err)
+			}
+			item := HostedResponseItem{
+				Kind:       hostedKindFromClaudeCall(blockType, block.Name),
+				NativeType: blockType,
+				ID:         block.Id,
+				CallID:     block.Id,
+				Name:       block.Name,
+				Status:     "in_progress",
+				Position:   position,
+				Action:     action,
+				Caller:     append(json.RawMessage(nil), block.Caller...),
+				ServerName: block.ServerName,
+				Raw:        rawBlock,
+			}
+			set.Items = append(set.Items, item)
+		case isClaudeHostedToolBlock(blockType):
+			rawBlock, err := kitutil.Marshal(block)
+			if err != nil {
+				return nil, set, fmt.Errorf("content[%d]: %w", position, err)
+			}
+			results, err := kitutil.Marshal(block.Content)
+			if err != nil {
+				return nil, set, fmt.Errorf("content[%d].content: %w", position, err)
+			}
+			failed, errorCode := claudeHostedResultFailure(blockType, results, block.IsError, block.ErrorCode)
+			status := "completed"
+			isError := block.IsError
+			if failed {
+				status = "failed"
+				if isError == nil {
+					value := true
+					isError = &value
+				}
+			}
+			set.Items = append(set.Items, HostedResponseItem{
+				Kind:       hostedKindFromClaudeResult(blockType),
+				NativeType: blockType,
+				ID:         block.ToolUseId,
+				CallID:     block.ToolUseId,
+				Status:     status,
+				Position:   position,
+				Results:    results,
+				ErrorCode:  errorCode,
+				IsError:    isError,
+				Raw:        rawBlock,
+			})
+		default:
+			clone.Content = append(clone.Content, block)
+			set.RegularPositions = append(set.RegularPositions, position)
+		}
+	}
+	return &clone, set, nil
+}
+
+func extractOpenAIHostedResponse(response any) (any, HostedResponseSet, error) {
+	var source *dto.OpenAIResponsesResponse
+	switch value := response.(type) {
+	case *dto.OpenAIResponsesResponse:
+		source = value
+	case dto.OpenAIResponsesResponse:
+		source = &value
+	default:
+		return nil, HostedResponseSet{}, fmt.Errorf("expected OpenAI Responses response, got %T", response)
+	}
+	clone := *source
+	clone.Output = make([]dto.ResponsesOutput, 0, len(source.Output))
+	set := HostedResponseSet{Source: types.RelayFormatOpenAIResponses, SourceLength: len(source.Output)}
+	for position := range source.Output {
+		output := source.Output[position]
+		if !isResponsesHostedOutput(output.Type) {
+			clone.Output = append(clone.Output, output)
+			set.RegularPositions = append(set.RegularPositions, position)
+			continue
+		}
+		rawOutput, err := kitutil.Marshal(output)
+		if err != nil {
+			return nil, set, fmt.Errorf("output[%d]: %w", position, err)
+		}
+		set.Items = append(set.Items, HostedResponseItem{
+			Kind:              hostedKindFromResponsesType(output.Type),
+			NativeType:        output.Type,
+			ID:                output.ID,
+			CallID:            output.CallId,
+			Name:              output.Name,
+			Status:            output.Status,
+			Position:          position,
+			Action:            append(json.RawMessage(nil), output.Action...),
+			Results:           append(json.RawMessage(nil), output.Results...),
+			Sources:           append(json.RawMessage(nil), output.Sources...),
+			Caller:            append(json.RawMessage(nil), output.Caller...),
+			Arguments:         append(json.RawMessage(nil), output.Arguments...),
+			Output:            append(json.RawMessage(nil), output.Output...),
+			Error:             append(json.RawMessage(nil), output.ItemError...),
+			ServerName:        output.ServerLabel,
+			ApprovalRequestID: output.ApprovalRequestID,
+			Tools:             append(json.RawMessage(nil), output.MCPTools...),
+			Raw:               rawOutput,
+		})
+	}
+	return &clone, set, nil
+}
+
+func extractGeminiHostedResponse(response any) (any, HostedResponseSet, error) {
+	var source *dto.GeminiChatResponse
+	switch value := response.(type) {
+	case *dto.GeminiChatResponse:
+		source = value
+	case dto.GeminiChatResponse:
+		source = &value
+	default:
+		return nil, HostedResponseSet{}, fmt.Errorf("expected Gemini response, got %T", response)
+	}
+	queries := geminichat.GroundingWebSearchQueries(source)
+	if len(queries) == 0 {
+		return source, HostedResponseSet{Source: types.RelayFormatGemini}, nil
+	}
+	action, err := kitutil.Marshal(map[string]any{
+		"type":    "search",
+		"queries": queries,
+	})
+	if err != nil {
+		return nil, HostedResponseSet{}, fmt.Errorf("marshal Gemini web-search action: %w", err)
+	}
+	// The Chat pivot emits the answer as the regular Responses output. Place
+	// the hosted call after that output, matching the stream bridge which only
+	// learns Gemini's queries once grounding metadata arrives near stream end.
+	set := HostedResponseSet{
+		Source:           types.RelayFormatGemini,
+		SourceLength:     2,
+		RegularPositions: []int{0},
+		Items: []HostedResponseItem{{
+			Kind:       KindWebSearch,
+			NativeType: "googleSearch",
+			ID:         fmt.Sprintf("ws_%s", kitutil.GetUUID()),
+			Status:     "completed",
+			Position:   1,
+			Action:     action,
+		}},
+	}
+	return source, set, nil
+}
+
+func attachOpenAIHostedResponse(response any, set HostedResponseSet) (any, []types.ConversionDiagnostic, error) {
+	target, ok := response.(*dto.OpenAIResponsesResponse)
+	if !ok || target == nil {
+		return nil, nil, fmt.Errorf("expected OpenAI Responses response, got %T", response)
+	}
+	var diagnostics []types.ConversionDiagnostic
+	hostedOutput := make([]positionedResponsesOutput, 0, len(set.Items))
+	convertedByID := make(map[string]int, len(set.Items)*2)
+	for index, item := range set.Items {
+		if set.Source == types.RelayFormatOpenAIResponses && len(item.Raw) > 0 {
+			var output dto.ResponsesOutput
+			if err := kitutil.Unmarshal(item.Raw, &output); err != nil {
+				return nil, diagnostics, fmt.Errorf("hosted_tools[%d]: %w", index, err)
+			}
+			hostedOutput = append(hostedOutput, positionedResponsesOutput{position: item.Position, output: output})
+			continue
+		}
+		outputType := responsesTypeFromHostedKind(item.Kind)
+		if outputType == "" {
+			diagnostics = append(diagnostics, responseSemanticLoss(
+				fmt.Sprintf("hosted_tools[%d]", index),
+				"hosted_tool_unrepresentable",
+				fmt.Sprintf("OpenAI Responses has no lossless response mapping for %q", item.NativeType),
+			))
+			continue
+		}
+		if isClaudeHostedResult(item.NativeType) {
+			outputIndex, exists := convertedByID[item.CallID]
+			if !exists {
+				diagnostics = append(diagnostics, responseSemanticLoss(
+					fmt.Sprintf("hosted_tools[%d].tool_use_id", index),
+					"hosted_tool_result_orphaned",
+					fmt.Sprintf("hosted-tool result references unknown call %q", item.CallID),
+				))
+				continue
+			}
+			output := &hostedOutput[outputIndex].output
+			output.Status = hostedCompletionStatus(item)
+			if item.Kind == KindMCP {
+				failed := hostedItemFailed(item)
+				var (
+					encoded    json.RawMessage
+					normalized bool
+					err        error
+				)
+				if failed {
+					encoded, normalized, err = responsesMCPErrorFromClaudeContent(item.Results, item.ErrorCode)
+				} else {
+					encoded, normalized, err = responsesMCPStringFromClaudeContent(item.Results)
+				}
+				if err != nil {
+					diagnostics = append(diagnostics, responseSemanticLoss(
+						fmt.Sprintf("hosted_tools[%d].content", index),
+						"mcp_result_unrepresentable",
+						err.Error(),
+					))
+					continue
+				}
+				if failed {
+					output.Output = nil
+					output.ItemError = encoded
+				} else {
+					output.Output = encoded
+					output.ItemError = nil
+				}
+				if normalized {
+					diagnostics = append(diagnostics, responsePresentationLoss(
+						fmt.Sprintf("hosted_tools[%d].content", index),
+						"mcp_text_result_normalized",
+						"Claude's single MCP text block was normalized to a Responses output string",
+					))
+				}
+			} else if item.Kind == KindWebSearch && rawJSONPresent(item.Results) {
+				diagnostics = append(diagnostics, responsePresentationLoss(
+					fmt.Sprintf("hosted_tools[%d].content", index),
+					"web_search_result_omitted",
+					"Claude web-search result content is provider-private and has no field on an OpenAI Responses web_search_call; completion status and citations remain available",
+				))
+			}
+			continue
+		}
+		output := dto.ResponsesOutput{
+			Type:   outputType,
+			ID:     firstNonEmpty(item.ID, item.CallID),
+			Status: hostedCompletionStatus(item),
+		}
+		switch item.Kind {
+		case KindWebSearch:
+			action, err := dto.NormalizeResponsesWebSearchAction(item.Action)
+			if err != nil {
+				return nil, diagnostics, fmt.Errorf("hosted_tools[%d].action: %w", index, err)
+			}
+			output.Action = action
+		case KindMCP:
+			if strings.TrimSpace(item.Name) == "" || strings.TrimSpace(item.ServerName) == "" {
+				diagnostics = append(diagnostics, responseSemanticLoss(
+					fmt.Sprintf("hosted_tools[%d]", index),
+					"mcp_identity_missing",
+					"Claude MCP output requires both name and server_name for Responses mapping",
+				))
+				continue
+			}
+			output.CallId = item.CallID
+			output.Name = item.Name
+			output.Caller = append(json.RawMessage(nil), item.Caller...)
+			output.ServerLabel = item.ServerName
+			output.ApprovalRequestID = item.ApprovalRequestID
+			output.MCPTools = append(json.RawMessage(nil), item.Tools...)
+			arguments := item.Arguments
+			if len(arguments) == 0 {
+				arguments = item.Action
+			}
+			encodedArguments, argumentErr := responsesMCPArgumentsFromClaude(arguments)
+			if argumentErr != nil {
+				diagnostics = append(diagnostics, responseSemanticLoss(
+					fmt.Sprintf("hosted_tools[%d].input", index),
+					"mcp_arguments_unrepresentable",
+					argumentErr.Error(),
+				))
+				continue
+			}
+			output.Arguments = encodedArguments
+		}
+		outputIndex := len(hostedOutput)
+		for _, key := range []string{item.ID, item.CallID} {
+			if key != "" {
+				convertedByID[key] = outputIndex
+			}
+		}
+		hostedOutput = append(hostedOutput, positionedResponsesOutput{position: item.Position, output: output})
+		if set.Source != types.RelayFormatOpenAIResponses {
+			diagnostics = append(diagnostics, responsePresentationLoss(
+				fmt.Sprintf("hosted_tools[%d]", index),
+				"hosted_tool_result_approximated",
+				"hosted-tool execution is preserved, but provider-specific result fields may differ",
+			))
+		}
+	}
+	merged, orderingDiagnostics := mergeResponsesOutput(target.Output, hostedOutput, set)
+	diagnostics = append(diagnostics, orderingDiagnostics...)
+	target.Output = merged
+	return target, diagnostics, nil
+}
+
+func attachClaudeHostedResponse(response any, set HostedResponseSet) (any, []types.ConversionDiagnostic, error) {
+	target, ok := response.(*dto.ClaudeResponse)
+	if !ok || target == nil {
+		return nil, nil, fmt.Errorf("expected Claude response, got %T", response)
+	}
+	var diagnostics []types.ConversionDiagnostic
+	hostedContent := make([]positionedClaudeBlocks, 0, len(set.Items))
+	for index, item := range set.Items {
+		if set.Source == types.RelayFormatClaude && len(item.Raw) > 0 {
+			var block dto.ClaudeMediaMessage
+			if err := kitutil.Unmarshal(item.Raw, &block); err != nil {
+				return nil, diagnostics, fmt.Errorf("hosted_tools[%d]: %w", index, err)
+			}
+			hostedContent = append(hostedContent, positionedClaudeBlocks{position: item.Position, blocks: []dto.ClaudeMediaMessage{block}})
+			continue
+		}
+		if set.Source == types.RelayFormatOpenAIResponses && item.Kind == KindWebSearch {
+			diagnostics = append(diagnostics, responseSemanticLoss(
+				fmt.Sprintf("hosted_tools[%d]", index),
+				"web_search_response_unrepresentable",
+				"Responses web-search execution cannot reconstruct Claude's required encrypted web_search_tool_result continuation state",
+			))
+			continue
+		}
+		name := claudeNameFromHostedKind(item.Kind)
+		if item.Kind == KindMCP {
+			name = item.Name
+		}
+		if name == "" {
+			diagnostics = append(diagnostics, responseSemanticLoss(
+				fmt.Sprintf("hosted_tools[%d]", index),
+				"hosted_tool_unrepresentable",
+				fmt.Sprintf("Claude has no lossless response mapping for %q", item.NativeType),
+			))
+			continue
+		}
+		var input any = map[string]any{}
+		if item.Kind == KindWebSearch {
+			webInput, inputErr := claudeWebSearchInputFromResponses(item.Action)
+			if inputErr != nil {
+				diagnostics = append(diagnostics, responseSemanticLoss(
+					fmt.Sprintf("hosted_tools[%d].action", index),
+					"web_search_action_unrepresentable",
+					inputErr.Error(),
+				))
+				continue
+			}
+			input = webInput
+		} else if item.Kind == KindMCP {
+			mcpInput, inputErr := claudeMCPInputFromResponses(item.Arguments)
+			if inputErr != nil {
+				diagnostics = append(diagnostics, responseSemanticLoss(
+					fmt.Sprintf("hosted_tools[%d].arguments", index),
+					"mcp_arguments_unrepresentable",
+					inputErr.Error(),
+				))
+				continue
+			}
+			input = mcpInput
+		} else if len(item.Action) > 0 {
+			if err := kitutil.Unmarshal(item.Action, &input); err != nil {
+				return nil, diagnostics, fmt.Errorf("hosted_tools[%d].action: %w", index, err)
+			}
+		}
+		callType := "server_tool_use"
+		if item.Kind == KindMCP {
+			callType = "mcp_tool_use"
+		}
+		blocks := []dto.ClaudeMediaMessage{{
+			Type:       callType,
+			Id:         item.ID,
+			Name:       name,
+			Input:      input,
+			Caller:     append(json.RawMessage(nil), item.Caller...),
+			ServerName: item.ServerName,
+		}}
+		result := item.Results
+		if item.Kind == KindMCP {
+			result = item.Output
+			if hostedItemFailed(item) && rawJSONPresent(item.Error) {
+				result = item.Error
+			}
+		} else if len(result) == 0 {
+			result = item.Sources
+		}
+		if len(result) > 0 && !(set.Source == types.RelayFormatOpenAIResponses && item.Kind == KindWebSearch) {
+			var content any
+			if item.Kind == KindMCP {
+				decoded, resultErr := claudeMCPContentFromResponsesString(result)
+				if resultErr != nil {
+					diagnostics = append(diagnostics, responseSemanticLoss(
+						fmt.Sprintf("hosted_tools[%d].output", index),
+						"mcp_result_unrepresentable",
+						resultErr.Error(),
+					))
+					continue
+				}
+				content = decoded
+			} else if err := kitutil.Unmarshal(result, &content); err != nil {
+				return nil, diagnostics, fmt.Errorf("hosted_tools[%d].results: %w", index, err)
+			}
+			isError := hostedItemFailed(item)
+			blocks = append(blocks, dto.ClaudeMediaMessage{
+				Type:      claudeResultTypeFromHostedKind(item.Kind),
+				ToolUseId: item.ID,
+				Content:   content,
+				IsError:   &isError,
+				ErrorCode: item.ErrorCode,
+			})
+		} else if len(result) > 0 && item.Kind == KindWebSearch {
+			diagnostics = append(diagnostics, responsePresentationLoss(
+				fmt.Sprintf("hosted_tools[%d].results", index),
+				"web_search_result_omitted",
+				"Responses web-search source metadata cannot reconstruct Claude's encrypted web_search_tool_result",
+			))
+		} else if item.Kind == KindMCP && (item.Status == "completed" || item.Status == "failed") {
+			diagnostics = append(diagnostics, responseSemanticLoss(
+				fmt.Sprintf("hosted_tools[%d]", index),
+				"mcp_result_missing",
+				fmt.Sprintf("Responses MCP output has status %q but no output or error", item.Status),
+			))
+		}
+		hostedContent = append(hostedContent, positionedClaudeBlocks{position: item.Position, blocks: blocks})
+		if set.Source != types.RelayFormatClaude {
+			diagnostics = append(diagnostics, responsePresentationLoss(
+				fmt.Sprintf("hosted_tools[%d]", index),
+				"hosted_tool_result_approximated",
+				"hosted-tool execution is preserved, but provider-specific result fields may differ",
+			))
+		}
+	}
+	merged, orderingDiagnostics := mergeClaudeContent(target.Content, hostedContent, set)
+	diagnostics = append(diagnostics, orderingDiagnostics...)
+	target.Content = merged
+	return target, diagnostics, nil
+}
+
+func mergeResponsesOutput(regular []dto.ResponsesOutput, hosted []positionedResponsesOutput, set HostedResponseSet) ([]dto.ResponsesOutput, []types.ConversionDiagnostic) {
+	if len(hosted) == 0 {
+		return regular, nil
+	}
+	if len(regular) == len(set.RegularPositions) {
+		byPosition := make(map[int][]dto.ResponsesOutput, len(hosted))
+		for _, item := range hosted {
+			byPosition[item.position] = append(byPosition[item.position], item.output)
+		}
+		regularByPosition := make(map[int]dto.ResponsesOutput, len(regular))
+		for index, position := range set.RegularPositions {
+			regularByPosition[position] = regular[index]
+		}
+		merged := make([]dto.ResponsesOutput, 0, len(regular)+len(hosted))
+		for position := 0; position < set.SourceLength; position++ {
+			merged = append(merged, byPosition[position]...)
+			if output, exists := regularByPosition[position]; exists {
+				merged = append(merged, output)
+			}
+		}
+		return merged, nil
+	}
+	before, after, exact := hostedOutsideRegularRange(hostedPositions(hosted), set.RegularPositions)
+	if exact {
+		merged := make([]dto.ResponsesOutput, 0, len(regular)+len(hosted))
+		for _, item := range before {
+			merged = append(merged, hosted[item].output)
+		}
+		merged = append(merged, regular...)
+		for _, item := range after {
+			merged = append(merged, hosted[item].output)
+		}
+		return merged, nil
+	}
+	merged := make([]dto.ResponsesOutput, 0, len(regular)+len(hosted))
+	for _, item := range hosted {
+		merged = append(merged, item.output)
+	}
+	merged = append(merged, regular...)
+	return merged, []types.ConversionDiagnostic{responseSemanticLoss(
+		"output",
+		"hosted_tool_order_unrepresentable",
+		"hosted-tool items were interleaved with content that the target converter coalesced, so their original order cannot be reconstructed",
+	)}
+}
+
+func mergeClaudeContent(regular []dto.ClaudeMediaMessage, hosted []positionedClaudeBlocks, set HostedResponseSet) ([]dto.ClaudeMediaMessage, []types.ConversionDiagnostic) {
+	if len(hosted) == 0 {
+		return regular, nil
+	}
+	if len(regular) == len(set.RegularPositions) {
+		byPosition := make(map[int][]dto.ClaudeMediaMessage, len(hosted))
+		for _, item := range hosted {
+			byPosition[item.position] = append(byPosition[item.position], item.blocks...)
+		}
+		regularByPosition := make(map[int]dto.ClaudeMediaMessage, len(regular))
+		for index, position := range set.RegularPositions {
+			regularByPosition[position] = regular[index]
+		}
+		merged := make([]dto.ClaudeMediaMessage, 0, len(regular)+len(hosted)*2)
+		for position := 0; position < set.SourceLength; position++ {
+			merged = append(merged, byPosition[position]...)
+			if block, exists := regularByPosition[position]; exists {
+				merged = append(merged, block)
+			}
+		}
+		return merged, nil
+	}
+	before, after, exact := hostedOutsideRegularRange(claudeHostedPositions(hosted), set.RegularPositions)
+	if exact {
+		merged := make([]dto.ClaudeMediaMessage, 0, len(regular)+len(hosted)*2)
+		for _, item := range before {
+			merged = append(merged, hosted[item].blocks...)
+		}
+		merged = append(merged, regular...)
+		for _, item := range after {
+			merged = append(merged, hosted[item].blocks...)
+		}
+		return merged, nil
+	}
+	merged := make([]dto.ClaudeMediaMessage, 0, len(regular)+len(hosted)*2)
+	for _, item := range hosted {
+		merged = append(merged, item.blocks...)
+	}
+	merged = append(merged, regular...)
+	return merged, []types.ConversionDiagnostic{responseSemanticLoss(
+		"content",
+		"hosted_tool_order_unrepresentable",
+		"hosted-tool blocks were interleaved with content that the target converter coalesced, so their original order cannot be reconstructed",
+	)}
+}
+
+func hostedPositions(items []positionedResponsesOutput) []int {
+	positions := make([]int, len(items))
+	for index := range items {
+		positions[index] = items[index].position
+	}
+	return positions
+}
+
+func claudeHostedPositions(items []positionedClaudeBlocks) []int {
+	positions := make([]int, len(items))
+	for index := range items {
+		positions[index] = items[index].position
+	}
+	return positions
+}
+
+func hostedOutsideRegularRange(hosted []int, regular []int) (before []int, after []int, exact bool) {
+	if len(regular) == 0 {
+		indices := make([]int, len(hosted))
+		for index := range hosted {
+			indices[index] = index
+		}
+		return indices, nil, true
+	}
+	firstRegular, lastRegular := regular[0], regular[len(regular)-1]
+	for index, position := range hosted {
+		switch {
+		case position < firstRegular:
+			before = append(before, index)
+		case position > lastRegular:
+			after = append(after, index)
+		default:
+			return nil, nil, false
+		}
+	}
+	return before, after, true
+}
+
+func hostedKindFromClaudeCall(blockType string, name string) Kind {
+	if blockType == "mcp_tool_use" {
+		return KindMCP
+	}
+	switch strings.TrimSpace(name) {
+	case "web_search":
+		return KindWebSearch
+	case "web_fetch":
+		return KindWebFetch
+	case "code_execution":
+		return KindCodeExecution
+	default:
+		return KindNative
+	}
+}
+
+func hostedKindFromClaudeResult(blockType string) Kind {
+	switch strings.TrimSuffix(blockType, "_tool_result") {
+	case "web_search":
+		return KindWebSearch
+	case "web_fetch":
+		return KindWebFetch
+	case "code_execution":
+		return KindCodeExecution
+	case "mcp":
+		return KindMCP
+	default:
+		return KindNative
+	}
+}
+
+func hostedKindFromResponsesType(outputType string) Kind {
+	normalized := strings.TrimSpace(outputType)
+	normalized = strings.TrimSuffix(normalized, "_output")
+	normalized = strings.TrimSuffix(normalized, "_call")
+	switch normalized {
+	case "web_search":
+		return KindWebSearch
+	case "file_search":
+		return KindFileSearch
+	case "code_interpreter", "local_shell":
+		return KindCodeExecution
+	case "computer":
+		return KindComputerUse
+	case "image_generation":
+		return KindImage
+	case "mcp":
+		return KindMCP
+	default:
+		return KindNative
+	}
+}
+
+func responsesTypeFromHostedKind(kind Kind) string {
+	switch kind {
+	case KindWebSearch:
+		return "web_search_call"
+	case KindMCP:
+		return "mcp_call"
+	default:
+		return ""
+	}
+}
+
+func claudeNameFromHostedKind(kind Kind) string {
+	switch kind {
+	case KindWebSearch:
+		return "web_search"
+	case KindWebFetch:
+		return "web_fetch"
+	case KindCodeExecution:
+		return ""
+	case KindMCP:
+		return "mcp"
+	default:
+		return ""
+	}
+}
+
+func isClaudeHostedResult(nativeType string) bool {
+	return nativeType == "mcp_tool_result" || strings.HasSuffix(nativeType, "_tool_result")
+}
+
+func hostedCompletionStatus(item HostedResponseItem) string {
+	if hostedItemFailed(item) {
+		return "failed"
+	}
+	if item.Status != "" && item.Status != "in_progress" || len(item.Results) > 0 || len(item.Output) > 0 {
+		return "completed"
+	}
+	return "in_progress"
+}
+
+func hostedItemFailed(item HostedResponseItem) bool {
+	return item.Status == "failed" || item.ErrorCode != "" || rawJSONPresent(item.Error) || item.IsError != nil && *item.IsError
+}
+
+func hostedErrorValue(item HostedResponseItem) json.RawMessage {
+	if len(item.Error) > 0 {
+		return append(json.RawMessage(nil), item.Error...)
+	}
+	if item.ErrorCode == "" {
+		return nil
+	}
+	encoded, _ := kitutil.Marshal(item.ErrorCode)
+	return encoded
+}
+
+func firstNonEmpty(values ...string) string {
+	for _, value := range values {
+		if value != "" {
+			return value
+		}
+	}
+	return ""
+}
+
+func rawJSONPresent(value json.RawMessage) bool {
+	normalized := strings.TrimSpace(string(value))
+	return normalized != "" && normalized != "null"
+}
+
+func claudeResultTypeFromHostedKind(kind Kind) string {
+	name := claudeNameFromHostedKind(kind)
+	if name == "mcp" {
+		return "mcp_tool_result"
+	}
+	return name + "_tool_result"
+}