feat: add agentic react agent example

adk/intro/http-sse-service/go.mod

@@ -5,7 +5,7 @@ go 1.24.9
 replace github.com/cloudwego/eino-examples => ../../..
 
 require (
-	github.com/cloudwego/eino v0.7.14
+	github.com/cloudwego/eino v0.9.0-alpha.2
 	github.com/cloudwego/eino-examples v0.0.0-00010101000000-000000000000
 	github.com/cloudwego/hertz v0.10.3
 	github.com/hertz-contrib/sse v0.1.0
@@ -51,7 +51,7 @@ require (
 	github.com/tidwall/sjson v1.2.5 // indirect
 	github.com/twitchyliquid64/golang-asm v0.15.1 // indirect
 	github.com/volcengine/volc-sdk-golang v1.0.199 // indirect
-	github.com/volcengine/volcengine-go-sdk v1.1.44 // indirect
+	github.com/volcengine/volcengine-go-sdk v1.2.4 // indirect
 	github.com/wk8/go-ordered-map/v2 v2.1.8 // indirect
 	github.com/yargevad/filepathx v1.0.0 // indirect
 	golang.org/x/arch v0.19.0 // indirect

adk/intro/http-sse-service/go.sum

@@ -79,8 +79,8 @@ github.com/bugsnag/panicwrap v1.2.0/go.mod h1:D/8v3kj0zr8ZAKg1AQ6crr+5VwKN5eIywR
 github.com/bytedance/gopkg v0.1.1/go.mod h1:576VvJ+eJgyCzdjS+c4+77QF3p7ubbtiKARP3TxducM=
 github.com/bytedance/gopkg v0.1.3 h1:TPBSwH8RsouGCBcMBktLt1AymVo2TVsBVCY4b6TnZ/M=
 github.com/bytedance/gopkg v0.1.3/go.mod h1:576VvJ+eJgyCzdjS+c4+77QF3p7ubbtiKARP3TxducM=
-github.com/bytedance/mockey v1.2.14 h1:KZaFgPdiUwW+jOWFieo3Lr7INM1P+6adO3hxZhDswY8=
-github.com/bytedance/mockey v1.2.14/go.mod h1:1BPHF9sol5R1ud/+0VEHGQq/+i2lN+GTsr3O2Q9IENY=
+github.com/bytedance/mockey v1.4.1 h1:M61HE/wajTkOHPKgBUKUUViaRoaMok26/ZqOSyq7ZtQ=
+github.com/bytedance/mockey v1.4.1/go.mod h1:1BPHF9sol5R1ud/+0VEHGQq/+i2lN+GTsr3O2Q9IENY=
 github.com/bytedance/sonic v1.14.2 h1:k1twIoe97C1DtYUo+fZQy865IuHia4PR5RPiuGPPIIE=
 github.com/bytedance/sonic v1.14.2/go.mod h1:T80iDELeHiHKSc0C9tubFygiuXoGzrkjKzX2quAx980=
 github.com/bytedance/sonic/loader v0.4.0 h1:olZ7lEqcxtZygCK9EKYKADnpQoYkRQxaeY2NYzevs+o=
@@ -104,11 +104,8 @@ github.com/clbanning/mxj v1.8.4/go.mod h1:BVjHeAH+rl9rs6f+QIpeRl0tfu10SXn1pUSa5P
 github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
 github.com/cloudwego/base64x v0.1.6 h1:t11wG9AECkCDk5fMSoxmufanudBtJ+/HemLstXDLI2M=
 github.com/cloudwego/base64x v0.1.6/go.mod h1:OFcloc187FXDaYHvrNIjxSe8ncn0OOM8gEHfghB2IPU=
-github.com/cloudwego/eino v0.7.8 h1:3a2j1UKZZuQ3SzqDToOI5g6lrlJ7xZEtMlNQkTgIvaI=
-github.com/cloudwego/eino v0.7.8/go.mod h1:nA8Vacmuqv3pqKBQbTWENBLQ8MmGmPt/WqiyLeB8ohQ=
-github.com/cloudwego/eino v0.7.11/go.mod h1:nA8Vacmuqv3pqKBQbTWENBLQ8MmGmPt/WqiyLeB8ohQ=
-github.com/cloudwego/eino v0.7.14-0.20251225084034-ff42791c540f/go.mod h1:nA8Vacmuqv3pqKBQbTWENBLQ8MmGmPt/WqiyLeB8ohQ=
-github.com/cloudwego/eino v0.7.14/go.mod h1:nA8Vacmuqv3pqKBQbTWENBLQ8MmGmPt/WqiyLeB8ohQ=
+github.com/cloudwego/eino v0.9.0-alpha.2 h1:YdNHQ1XqPnAe1EEy3Hm5oDzOnoPwizHCjaSdnF7iHjw=
+github.com/cloudwego/eino v0.9.0-alpha.2/go.mod h1:2gsj+xyPFnmZfz7jtnbA6VghaaJsThYh2appzPeslRE=
 github.com/cloudwego/eino-ext/components/model/ark v0.1.45 h1:LWvSHJVlvS1S/IxN9XUKNw/MI0I7YPePt3LMNxyCrZ0=
 github.com/cloudwego/eino-ext/components/model/ark v0.1.45/go.mod h1:e8P5dGVI/JMQ1FYNgmu5EFRWA8fivBc6NwNJ9g8FBK8=
 github.com/cloudwego/eino-ext/components/model/openai v0.1.5 h1:+yvGbTPw93li9GSmdm6Rix88Yy8AXg5NNBcRbWx3CQU=
@@ -515,8 +512,8 @@ github.com/urfave/cli/v2 v2.3.0/go.mod h1:LJmUH05zAU44vOAcrfzZQKsZbVcdbOG8rtL3/X
 github.com/volcengine/volc-sdk-golang v1.0.23/go.mod h1:AfG/PZRUkHJ9inETvbjNifTDgut25Wbkm2QoYBTbvyU=
 github.com/volcengine/volc-sdk-golang v1.0.199 h1:zv9QOqTl/IsLwtfC37GlJtcz6vMAHi+pjq8ILWjLYUc=
 github.com/volcengine/volc-sdk-golang v1.0.199/go.mod h1:stZX+EPgv1vF4nZwOlEe8iGcriUPRBKX8zA19gXycOQ=
-github.com/volcengine/volcengine-go-sdk v1.1.44 h1:WLoLlzt67ZlJeow55PPx65/Mh52DewVXqkHcFSodM9w=
-github.com/volcengine/volcengine-go-sdk v1.1.44/go.mod h1:oxoVo+A17kvkwPkIeIHPVLjSw7EQAm+l/Vau1YGHN+A=
+github.com/volcengine/volcengine-go-sdk v1.2.4 h1:smBdDwwkXoXldCuumuZDJQASlAgVUIeL/RQ26D0OgI4=
+github.com/volcengine/volcengine-go-sdk v1.2.4/go.mod h1:oxoVo+A17kvkwPkIeIHPVLjSw7EQAm+l/Vau1YGHN+A=
 github.com/wk8/go-ordered-map/v2 v2.1.8 h1:5h/BUHu93oj4gIdvHHHGsScSTMijfx5PeYkE/fJgbpc=
 github.com/wk8/go-ordered-map/v2 v2.1.8/go.mod h1:5nJHM5DyteebpVlHnWMV0rPz6Zp7+xBAnxjb1X5vnTw=
 github.com/x-cray/logrus-prefixed-formatter v0.5.2 h1:00txxvfBM9muc0jiLIEAkAcIMJzfthRT6usrui8uGmg=

flow/agent/react/agentic/callback.go

@@ -0,0 +1,179 @@
+/*
+ * Copyright 2026 CloudWeGo Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package main
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"strings"
+
+	"github.com/bytedance/sonic"
+	"github.com/cloudwego/eino-examples/internal/logs"
+	"github.com/cloudwego/eino-ext/components/model/agenticark"
+	"github.com/cloudwego/eino/callbacks"
+	"github.com/cloudwego/eino/components/model"
+	"github.com/cloudwego/eino/schema"
+	"github.com/volcengine/volcengine-go-sdk/service/arkruntime/model/responses"
+)
+
+func newAgenticModelCallback() *agenticModelCallback {
+	return &agenticModelCallback{}
+}
+
+type agenticModelCallback struct{}
+
+func (a *agenticModelCallback) OnEndWithStreamOutput(ctx context.Context, runInfo *callbacks.RunInfo,
+	output *schema.StreamReader[*model.AgenticCallbackOutput]) context.Context {
+
+	printHeader(fmt.Sprintf("AgenticModel Name: %s", runInfo.Name), "\033[36m")
+
+	go func() {
+		var (
+			lastBlockType schema.ContentBlockType
+			lineLength    int
+		)
+
+		for {
+			chunk, err := output.Recv()
+			if err != nil {
+				if errors.Is(err, io.EOF) {
+					break
+				}
+				logs.Errorf("read streaming output failed, err: %v", err)
+				return
+			}
+
+			if chunk.Message == nil {
+				continue
+			}
+
+			for _, block := range chunk.Message.ContentBlocks {
+				switch block.Type {
+				case schema.ContentBlockTypeReasoning:
+					if lastBlockType != block.Type {
+						printHeader("reasoning", "\033[33m")
+						lineLength = 0
+					}
+
+					lineLength = printWrapped(block.Reasoning.Text, lineLength)
+
+					lastBlockType = block.Type
+
+				case schema.ContentBlockTypeFunctionToolCall:
+					if lastBlockType != block.Type {
+						printHeader(fmt.Sprintf("call function tool: %s", block.FunctionToolCall.Name), "\033[35m")
+						lineLength = 0
+					}
+
+					lineLength = printWrapped(block.FunctionToolCall.Arguments, lineLength)
+
+					lastBlockType = block.Type
+
+				case schema.ContentBlockTypeServerToolCall:
+					if lastBlockType != block.Type {
+						printHeader(fmt.Sprintf("call server tool: %s", block.ServerToolCall.Name), "\033[35m")
+						lineLength = 0
+					}
+
+					status, ok := agenticark.GetItemStatus(block)
+					if ok && status != responses.ItemStatus_completed.String() {
+						fmt.Print(status + "...\n\n")
+					}
+					if block.ServerToolCall.Arguments != nil {
+						fmt.Print(responses.ItemStatus_completed.String() + "!\n\n")
+						args, _ := sonic.MarshalIndent(block.ServerToolCall.Arguments, "", "  ")
+						fmt.Println(string(args))
+						lineLength = 0
+					}
+
+					lastBlockType = block.Type
+
+				case schema.ContentBlockTypeServerToolResult:
+					if lastBlockType != block.Type {
+						printHeader(fmt.Sprintf("server tool result: %s", block.ServerToolResult.Name), "\033[32m")
+						lineLength = 0
+					}
+					if block.ServerToolResult.Result != nil {
+						res, _ := sonic.MarshalIndent(block.ServerToolResult.Result, "", "  ")
+						fmt.Println(string(res))
+						lineLength = 0
+					}
+
+					lastBlockType = block.Type
+
+				case schema.ContentBlockTypeAssistantGenText:
+					if lastBlockType != block.Type {
+						printHeader("assistant generated text", "\033[36m")
+						lineLength = 0
+					}
+
+					lineLength = printWrapped(block.AssistantGenText.Text, lineLength)
+
+					lastBlockType = block.Type
+				}
+			}
+		}
+	}()
+
+	return ctx
+}
+
+func printWrapped(content string, currentLength int) int {
+	for _, r := range content {
+		if r == '\n' {
+			currentLength = 0
+			fmt.Print(string(r))
+			continue
+		}
+
+		w := 1
+		if r > 127 {
+			w = 2
+		}
+
+		if currentLength+w > 120 {
+			fmt.Print("\n")
+			currentLength = 0
+		}
+
+		fmt.Print(string(r))
+		currentLength += w
+	}
+	return currentLength
+}
+
+func printHeader(content string, color string) {
+	const lineLength = 60
+	separator := strings.Repeat("=", lineLength)
+
+	contentLength := len(content)
+	if contentLength >= lineLength {
+		// Content too long, just print it within separators
+		fmt.Printf("\n\n%s%s\n%s\n%s\033[0m\n\n", color, separator, content, separator)
+		return
+	}
+
+	padding := lineLength - contentLength
+	leftPad := padding / 2
+
+	// Create padding string with spaces
+	padStr := strings.Repeat(" ", leftPad)
+
+	fmt.Printf("\n\n%s%s\n%s%s\n%s\033[0m\n\n", color, separator, padStr, content, separator)
+}

flow/agent/react/agentic/main.go

@@ -0,0 +1,130 @@
+/*
+ * Copyright 2026 CloudWeGo Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package main
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"log"
+	"os"
+
+	"github.com/bytedance/sonic"
+	"github.com/cloudwego/eino-ext/components/model/agenticark"
+	"github.com/cloudwego/eino/components/tool"
+	"github.com/cloudwego/eino/compose"
+	"github.com/cloudwego/eino/schema"
+	"github.com/cloudwego/eino/utils/callbacks"
+	"github.com/volcengine/volcengine-go-sdk/service/arkruntime/model/responses"
+)
+
+func main() {
+	ctx := context.Background()
+
+	am, err := agenticark.New(ctx, &agenticark.Config{
+		Model:  os.Getenv("ARK_MODEL_ID"),
+		APIKey: os.Getenv("ARK_API_KEY"),
+		Thinking: &responses.ResponsesThinking{
+			Type: responses.ThinkingType_enabled.Enum(),
+		},
+		ServerTools: []*agenticark.ServerToolConfig{
+			{
+				WebSearch: &responses.ToolWebSearch{
+					Type: responses.ToolType_web_search,
+				},
+			},
+		},
+		Reasoning: &responses.ResponsesReasoning{
+			Effort: responses.ReasoningEffort_low,
+		},
+	})
+	if err != nil {
+		log.Fatalf("failed to create agentic model, err=%v", err)
+	}
+
+	r, err := NewAgent(ctx, &AgentConfig{
+		Model: am,
+		ToolsConfig: compose.ToolsNodeConfig{
+			Tools: []tool.BaseTool{
+				&SummarizeNewsTool{},
+				&GetUserLocationTool{},
+			},
+		},
+		ToolReturnDirectly: map[string]struct{}{
+			summarizeNewsToolName: {},
+		},
+	})
+	if err != nil {
+		log.Fatalf("failed to create agent, err=%v", err)
+	}
+
+	input := []*schema.AgenticMessage{
+		schema.SystemAgenticMessage("You are a news assistant that helps users search for recent news. " +
+			"Before using the `summarize_news` tool, " +
+			"You MUST use the `get_user_location` tool to get the user's country." +
+			"You MUST use the `summarize_news` tool to summarize the news and return the result."),
+		schema.UserAgenticMessage("What news has been happening in the last three days?"),
+	}
+
+	cb := callbacks.NewHandlerHelper().AgenticModel(&callbacks.AgenticModelCallbackHandler{
+		OnEndWithStreamOutput: newAgenticModelCallback().OnEndWithStreamOutput,
+	}).Handler()
+
+	sr, err := r.Stream(ctx, input, WithComposeOptions(compose.WithCallbacks(cb)))
+	if err != nil {
+		log.Fatalf("failed to stream, err=%v", err)
+	}
+
+	var msgs []*schema.AgenticMessage
+	for {
+		msg, err := sr.Recv()
+		if err != nil {
+			if err == io.EOF {
+				break
+			}
+			log.Fatalf("failed to recv, err=%v", err)
+		}
+		msgs = append(msgs, msg)
+	}
+
+	msg, err := schema.ConcatAgenticMessages(msgs)
+	if err != nil {
+		log.Fatalf("failed to concat messages, err=%v", err)
+	}
+
+	printHeader("final output", "\033[36m")
+
+	for _, block := range msg.ContentBlocks {
+		switch block.Type {
+		case schema.ContentBlockTypeFunctionToolResult:
+			var res *SummarizeNewsToolInput
+			if err = sonic.UnmarshalString(block.FunctionToolResult.Result, &res); err != nil {
+				log.Fatalf("failed to unmarshal function tool result, err=%v", err)
+			}
+
+			b, err := sonic.MarshalIndent(res.News, "", "  ")
+			if err != nil {
+				log.Fatalf("failed to marshal function tool result, err=%v", err)
+			}
+
+			fmt.Println(string(b))
+
+		default:
+			fmt.Println(fmt.Sprintf("%s", block))
+		}
+	}
+}