LangChain4j Agent

Since Camel 4.14

Only producer is supported

The LangChain4j Agent component provides comprehensive AI agent capabilities by integrating with the LangChain4j library. This component supports advanced AI agent patterns including tool calling, MCP (Model Context Protocol) integration, conversation memory, retrieval-augmented generation (RAG), and input/output guardrails.

Features

The LangChain4j Agent component offers the following key features:

  • Agent-Based Architecture: Flexible agent creation using the Agent API interface

  • Tool Integration: Seamless integration with Camel routes via the langchain4j-tools component

  • MCP Tools: Integration with Model Context Protocol (MCP) tools for external system access

  • Conversation Memory: Persistent chat memory for maintaining conversation context

  • RAG Support: Integration with retrieval systems for naive and advanced RAG

  • Guardrails: Input and output validation and transformation

  • Configuration Flexibility: Centralized agent configuration using AgentConfiguration

  • Multimodal Content: Support for images, PDFs, audio, video, and text files from file-based Camel components

Component Options

The component has been simplified to use only two main options:

  • agent: Reference to an Agent implementation registered in the Camel registry

  • tags: Tags for discovering and calling Camel route tools (optional)

All other configuration (chat models, memory, RAG, guardrails, custom tools, MCP clients) is now handled through the AgentConfiguration when creating agents.

URI format

langchain4j-agent:agentId[?options]

Where agentId is a unique identifier for the agent instance.

Configuring Options

Camel components are configured on two separate levels:

  • component level

  • endpoint level

Configuring Component Options

At the component level, you set general and shared configurations that are, then, inherited by the endpoints. It is the highest configuration level.

For example, a component may have security settings, credentials for authentication, urls for network connection and so forth.

Some components only have a few options, and others may have many. Because components typically have pre-configured defaults that are commonly used, then you may often only need to configure a few options on a component; or none at all.

You can configure components using:

  • the Component DSL.

  • in a configuration file (application.properties, *.yaml files, etc).

  • directly in the Java code.

Configuring Endpoint Options

You usually spend more time setting up endpoints because they have many options. These options help you customize what you want the endpoint to do. The options are also categorized into whether the endpoint is used as a consumer (from), as a producer (to), or both.

Configuring endpoints is most often done directly in the endpoint URI as path and query parameters. You can also use the Endpoint DSL and DataFormat DSL as a type safe way of configuring endpoints and data formats in Java.

A good practice when configuring options is to use Property Placeholders.

Property placeholders provide a few benefits:

  • They help prevent using hardcoded urls, port numbers, sensitive information, and other settings.

  • They allow externalizing the configuration from the code.

  • They help the code to become more flexible and reusable.

The following two sections list all the options, firstly for the component followed by the endpoint.

Component Options

The LangChain4j Agent component supports 6 options, which are listed below.

Name Description Default Type

agent (producer)

Autowired The agent to use for the component.

Agent

agentFactory (producer)

Autowired The agent factory to use for creating agents if no Agent is provided.

AgentFactory

configuration (producer)

The configuration.

LangChain4jAgentConfiguration

lazyStartProducer (producer)

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

false

boolean

tags (producer)

Tags for discovering and calling Camel route tools.

String

autowiredEnabled (advanced)

Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc.

true

boolean

Endpoint Options

The LangChain4j Agent endpoint is configured using URI syntax:

langchain4j-agent:agentId

With the following path and query parameters:

Path Parameters (1 parameters)

Name Description Default Type

agentId (producer)

Required The Agent id.

String

Query Parameters (4 parameters)

Name Description Default Type

agent (producer)

Autowired The agent to use for the component.

Agent

agentFactory (producer)

Autowired The agent factory to use for creating agents if no Agent is provided.

AgentFactory

tags (producer)

Tags for discovering and calling Camel route tools.

String

lazyStartProducer (producer (advanced))

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

false

boolean

Message Headers

The LangChain4j Agent component supports 4 message header(s), which is/are listed below:

Name Description Default Type

CamelLangChain4jAgentSystemMessage (producer)

Constant: SYSTEM_MESSAGE

The system prompt.

String

CamelLangChain4jAgentMemoryId (producer)

Constant: MEMORY_ID

Memory ID.

Object

CamelLangChain4jAgentUserMessage (producer)

Constant: USER_MESSAGE

The user message to accompany file content when using WrappedFile as input.

String

CamelLangChain4jAgentMediaType (producer)

Constant: MEDIA_TYPE

The media type (MIME type) of the file content. Overrides auto-detection from file extension.

String

Spring Boot Auto-Configuration

When using langchain4j-agent with Spring Boot make sure to use the following Maven dependency to have support for auto configuration:

<dependency>
  <groupId>org.apache.camel.springboot</groupId>
  <artifactId>camel-langchain4j-agent-starter</artifactId>
  <version>x.x.x</version>
  <!-- use the same version as your Camel core version -->
</dependency>

The component supports 7 options, which are listed below.

Name Description Default Type

camel.component.langchain4j-agent.agent

The agent to use for the component. The option is a org.apache.camel.component.langchain4j.agent.api.Agent type.

Agent

camel.component.langchain4j-agent.agent-factory

The agent factory to use for creating agents if no Agent is provided. The option is a org.apache.camel.component.langchain4j.agent.api.AgentFactory type.

AgentFactory

camel.component.langchain4j-agent.autowired-enabled

Whether autowiring is enabled. This is used for automatic autowiring options (the option must be marked as autowired) by looking up in the registry to find if there is a single instance of matching type, which then gets configured on the component. This can be used for automatic configuring JDBC data sources, JMS connection factories, AWS Clients, etc.

true

Boolean

camel.component.langchain4j-agent.configuration

The configuration. The option is a org.apache.camel.component.langchain4j.agent.LangChain4jAgentConfiguration type.

LangChain4jAgentConfiguration

camel.component.langchain4j-agent.enabled

Whether to enable auto configuration of the langchain4j-agent component. This is enabled by default.

Boolean

camel.component.langchain4j-agent.lazy-start-producer

Whether the producer should be started lazy (on the first message). By starting lazy you can use this to allow CamelContext and routes to startup in situations where a producer may otherwise fail during starting and cause the route to fail being started. By deferring this startup to be lazy then the startup failure can be handled during routing messages via Camel’s routing error handlers. Beware that when the first message is processed then creating and starting the producer may take a little time and prolong the total processing time of the processing.

false

Boolean

camel.component.langchain4j-agent.tags

Tags for discovering and calling Camel route tools.

String

Usage

Creating Custom Agents

Starting from Camel 4.14, the LangChain4j Agent component uses an agent-based architecture where agents are created by implementing the org.apache.camel.component.langchain4j.agent.api.Agent interface. The component provides two built-in agent implementations:

  • AgentWithMemory - For chat interactions with conversation history

  • AgentWithoutMemory - For stateless chat interactions

Agent Configuration

Agents are configured using the AgentConfiguration class which provides a fluent API for setting up:

  • Chat Model

  • Chat Memory Provider (for memory-enabled agents)

  • Retrieval Augmentor (for RAG functionality)

  • Input and Output Guardrails

Creating an Agent without Memory

// Create and configure the chat model
ChatModel chatModel = OpenAiChatModel.builder()
    .apiKey(openApiKey)
    .modelName(GPT_3_5_TURBO)
    .temperature(0.3)
    .timeout(ofSeconds(3000))
    .build();

// Create agent configuration
AgentConfiguration configuration = new AgentConfiguration()
    .withChatModel(chatModel)
    .withInputGuardrailClasses(List.of())
    .withOutputGuardrailClasses(List.of());

// Create the agent
Agent simpleAgent = new AgentWithoutMemory(configuration);

// Register the agent in the Camel context
context.getRegistry().bind("simpleAgent", simpleAgent);

Use the agent in your Camel route:

from("direct:chat")
    .to("langchain4j-agent:test?agent=#simpleAgent")

Creating an Agent with Memory

// Create chat model (same as above)
ChatModel chatModel = OpenAiChatModel.builder()...

// Create memory provider
ChatMemoryProvider memoryProvider = memoryId -> MessageWindowChatMemory.builder()
    .id(memoryId)
    .maxMessages(10)
    .chatMemoryStore(persistentStore) // Your persistent store implementation
    .build();

// Create agent configuration with memory
AgentConfiguration configuration = new AgentConfiguration()
    .withChatModel(chatModel)
    .withChatMemoryProvider(memoryProvider)
    .withInputGuardrailClasses(List.of())
    .withOutputGuardrailClasses(List.of());

// Create the agent
Agent memoryAgent = new AgentWithMemory(configuration);

// Register the agent
context.getRegistry().bind("memoryAgent", memoryAgent);

Add the camel-langchain4j-agent-api dependency to access the Agent API classes in your application:

<dependency>
    <groupId>org.apache.camel</groupId>
    <artifactId>camel-langchain4j-agent-api</artifactId>
    <version>x.x.x</version>
</dependency>

Basic Chat with only a userMessage

For simple chat interactions, you can use an agent without memory.

from("direct:chat")
    .to("langchain4j-agent:simple?agent=#simpleAgent")

The body can either contain the prompt as a String, or you can create an object of type org.apache.camel.component.langchain4j.agent.api.AiAgentBody containing the userMessage.

Usage example with a body as String:
var prompt = "What is Apache Camel";

String response = template.requestBody("direct:chat", prompt, String.class);
Usage example with a body as AiAgentBody:
var prompt = "What is Apache Camel";
AiAgentBody body = new AiAgentBody(prompt);

String response = template.requestBody("direct:chat", body, String.class);

Basic Chat with user and system messages

For chat interactions with system prompts, you can use an agent without memory.

from("direct:chat")
    .to("langchain4j-agent:simple?agent=#simpleAgent")

The body can either contain the user prompt as a String and specifying the CamelLangChain4jAgentSystemMessage header for the system prompt, or you can create an object of type org.apache.camel.component.langchain4j.agent.api.AiAgentBody containing both userMessage and systemMessage.

Usage example with a body as String:
var userPrompt = "Write a short story about a lost cat.";
var systemPrompt = "You are a whimsical storyteller. Your responses should be imaginative, descriptive, and always include a touch of magic. Start every story with 'Once upon a starlit night...";

String response = template.requestBodyAndHeader("direct:chat",
                userPrompt, "CamelLangChain4jAgentSystemMessage", systemPrompt , String.class);
Usage example with a body as AiAgentBody:
var userPrompt = "Write a short story about a lost cat.";
var systemPrompt = "You are a whimsical storyteller. Your responses should be imaginative, descriptive, and always include a touch of magic. Start every story with 'Once upon a starlit night...";

AiAgentBody body = new AiAgentBody()
                .withUserMessage(userPrompt)
                .withSystemMessage(systemPrompt);

String response = template.requestBody("direct:chat", body, String.class);

Chat with Tools

Integrate with Camel routes as tools. The LangChain4j Agent component integrates with Camel Routes defined using the Camel LangChain4j Tools component via the tags parameter.

// Define tool routes
from("langchain4j-tools:userDb?tags=users&description=Query user database&parameter.userId=string")
    .setBody(constant("{\"name\": \"John Doe\", \"id\": \"123\"}"));

from("langchain4j-tools:weather?tags=weather&description=Get weather information&parameter.city=string")
    .setBody(constant("{\"weather\": \"sunny\", \"temperature\": \"22°C\"}"));

// Agent with tools (using the created agent)
from("direct:chat")
    .to("langchain4j-agent:tools?agent=#simpleAgent&tags=users,weather");
Usage example :
var userPrompt = "Can you tell me the name of user 123 and the weather in New York?";
var systemPrompt = "You are a helpful assistant that can access user database and weather information. Use the available tools to provide accurate information.";

String response = template.requestBodyAndHeader("direct:chat",
                userPrompt, "CamelLangChain4jAgentSystemMessage", systemPrompt , String.class);

There’s no need to add Camel LangChain4j Tools component as a dependency when using the tools with LangChain4j Agent component.

Custom LangChain4j Tools

You can also add custom LangChain4j tools using the @Tool annotation. These tools are passed directly to the agent via the customTools configuration parameter.

Creating Custom LangChain4j Tools

Create a class with methods annotated with @Tool:

import dev.langchain4j.agent.tool.P;
import dev.langchain4j.agent.tool.Tool;

public class CalculatorTool {

    @Tool("Adds two numbers")
    public int add(@P("First number") int a, @P("Second number") int b) {
        return a + b;
    }

    @Tool("Multiplies two numbers")
    public int multiply(@P("First number") int a, @P("Second number") int b) {
        return a * b;
    }

    @Tool("Gets the square root of a number")
    public double sqrt(@P("Number") double x) {
        return Math.sqrt(x);
    }
}

Using Custom LangChain4j Tools with Agent

Pass your custom tool instances to the agent configuration:

// Create tool instances
CalculatorTool calculator = new CalculatorTool();
WeatherTool weather = new WeatherTool();

// Create agent configuration with custom tools
AgentConfiguration config = new AgentConfiguration()
    .withChatModel(chatModel)
    .withCustomTools(Arrays.asList(calculator, weather));

// Create agent
Agent agent = new AgentWithoutMemory(config);

// Register agent in Camel context
context.getRegistry().bind("customToolsAgent", agent);

Route Configuration

Use the agent with custom tools in your routes:

from("direct:chat")
    .to("langchain4j-agent:assistant?agent=#customToolsAgent")
    .to("mock:agent-response");

Usage Example

String response = template.requestBody("direct:chat",
    "Calculate 10 * 5 and tell me the weather in Paris", String.class);

Custom LangChain4j tools are executed directly by the LangChain4j framework. No additional configuration or tool Executor is needed for tool execution.

Mixed Tools (Camel Routes + Custom LangChain4j Tools)

You can combine both Camel route tools (via tags) and custom LangChain4j tools (via customTools) in the same agent:

// Define Camel route tools
from("langchain4j-tools:weatherService?tags=weather&description=Get current weather information&parameter.location=string")
    .setBody(constant("{\"weather\": \"sunny\", \"location\": \"Current Location\"}"));

// Create custom tool instances
CalculatorTool calculator = new CalculatorTool();
StringTool stringTool = new StringTool();

// Create agent configuration with both types of tools
AgentConfiguration config = new AgentConfiguration()
    .withChatModel(chatModel)
    .withCustomTools(Arrays.asList(calculator, stringTool));

// Create agent
Agent agent = new AgentWithMemory(config);

// Register agent in Camel context
context.getRegistry().bind("mixedToolsAgent", agent);

Route Configuration with Mixed Tools

from("direct:chat")
    .to("langchain4j-agent:assistant?agent=#mixedToolsAgent&tags=weather")
    .to("mock:agent-response");

Usage Example

String response = template.requestBody("direct:chat",
    "Calculate 10 * 5 and tell me the weather in London", String.class);

When using mixed tools, Camel route tools are discovered dynamically via the tags parameter, while custom LangChain4j tools are provided statically via the customTools configuration.

MCP (Model Context Protocol) Tools

The LangChain4j Agent component supports integration with MCP (Model Context Protocol) tools, allowing agents to interact with external systems and services through standardized protocols.

Configuring MCP Clients

To use MCP tools with your agent, you need to configure MCP clients in your AgentConfiguration:

// Create MCP transport for filesystem server
McpTransport filesystemTransport = new StdioMcpTransport.Builder()
    .command(Arrays.asList("npx", "-y", "@modelcontextprotocol/server-filesystem", "/path/to/directory"))
    .logEvents(true)
    .build();

// Create MCP client
McpClient filesystemClient = new DefaultMcpClient.Builder()
    .transport(filesystemTransport)
    .build();

// Create agent configuration with MCP clients
AgentConfiguration config = new AgentConfiguration()
    .withChatModel(chatModel)
    .withMcpClients(Arrays.asList(filesystemClient));

// Create agent
Agent agent = new AgentWithoutMemory(config);

MCP Tool Filtering

You can apply filters to control which MCP tools are available to your agent:

// Create security filter to only allow read operations
BiPredicate<McpClient, ToolSpecification> securityFilter = (client, toolSpec) -> {
    String toolName = toolSpec.name().toLowerCase();
    // Only allow read operations for safety
    return toolName.contains("read") || toolName.contains("list") || toolName.contains("get");
};

AgentConfiguration config = new AgentConfiguration()
    .withChatModel(chatModel)
    .withMcpClients(Arrays.asList(filesystemClient))
    .withMcpToolProviderFilter(securityFilter);

Complete MCP Example

Here’s a complete example showing how to use MCP tools with an agent:

// Create MCP client for filesystem access
McpTransport transport = new StdioMcpTransport.Builder()
    .command(Arrays.asList("npx", "-y", "@modelcontextprotocol/server-filesystem", "/tmp"))
    .logEvents(true)
    .build();

McpClient mcpClient = new DefaultMcpClient.Builder()
    .transport(transport)
    .build();

// Create agent with MCP tools
AgentConfiguration config = new AgentConfiguration()
    .withChatModel(chatModel)
    .withMcpClient(mcpClient);

Agent agent = new AgentWithoutMemory(config);

// Register agent in Camel context
context.getRegistry().bind("mcpAgent", agent);

Route Configuration with MCP Tools

from("direct:chat")
    .to("langchain4j-agent:assistant?agent=#mcpAgent")
    .to("mock:agent-response");

Usage Example with MCP Tools

String response = template.requestBody("direct:chat",
    "Can you list the files in the current directory and read the content of file.txt?", String.class);

RAG Integration

RAG (Retrieval-Augmented Generation) is supported by configuring a RetrievalAugmentor in the AgentConfiguration. Create an agent with RAG capabilities:

// Create the retrieval augmentor (shown below)
RetrievalAugmentor retrievalAugmentor = createRetrievalAugmentor();

// Create agent configuration with RAG
AgentConfiguration configuration = new AgentConfiguration()
    .withChatModel(chatModel)
    .withRetrievalAugmentor(retrievalAugmentor)
    .withInputGuardrailClasses(List.of())
    .withOutputGuardrailClasses(List.of());

Agent ragAgent = new AgentWithoutMemory(configuration);
context.getRegistry().bind("ragAgent", ragAgent);

// Use the RAG agent
from("direct:chat")
    .to("langchain4j-agent:rag?agent=#ragAgent")
Usage example with Retrieval Augmentor serving as naive RAG :
// creating the retrieval Augmentor
EmbeddingStoreContentRetriever contentRetriever = EmbeddingStoreContentRetriever.builder()
                .embeddingStore(embeddingStore) // the embedding store should be defined
                .embeddingModel(embeddingModel) // the embedding model should be defined
                .maxResults(3)
                .minScore(0.6)
                .build();

RetrievalAugmentor retrievalAugmentor = DefaultRetrievalAugmentor.builder()
                .contentRetriever(contentRetriever)
                // other options or steps can be included for Advanced RAG
                .build();

// bind the retrievalAugmentor in the context
context.getRegistry().bind("retrievalAugmentor", retrievalAugmentor);

// using the producer
String response = template.requestBody("direct:chat", body, String.class);

Chat with Memory

Memory functionality is supported by using AgentWithMemory and configuring a ChatMemoryProvider in the AgentConfiguration. The memory works for multiple users/sessions.

The component requires using a Chat Memory Provider that uses a persistent memory store.

The memory works for multiple users/sessions. For each context window, the users needs to set the memory ID: - By setting the Header CamelLangChain4jAgentMemoryId. This supposes that user is using a body as String. - By setting the AiAgentBody.memoryId field. This supposes that that user is using a body as AiAgentBody.

Example of Route with Memory Agent
from("direct:chat")
    .to("langchain4j-agent:memory?agent=#memoryAgent")
Example of usage with AiAgentBody
// Example of creating a Chat Memory Provider : Create a message window memory that keeps the last 10 messages
        ChatMemoryProvider chatMemoryProvider = memoryId -> MessageWindowChatMemory.builder()
                .id(memoryId)
                .maxMessages(10)
                .chatMemoryStore(store) // the Chat Memory store is previously created
                .build();

// bind the chat memory provider in the context
context.getRegistry().bind("chatMemoryProvider", chatMemoryProvider);


AiAgentBody request = new AiAgentBody("Hello!", null, "session-123");
String response = template.requestBody("direct:chat", request, String.class);

Input and Output Guardrails

Guardrails validate and filter AI interactions to ensure security and quality. The LangChain4j Agent component provides both custom guardrail support and a set of production-ready built-in guardrails.

Using Custom Guardrails

Create classes defining InputGuardrails and OutputGuardrails as defined in the LangChain4j Guardrails documentation page.

// Create agent configuration with custom guardrails
AgentConfiguration configuration = new AgentConfiguration()
    .withChatModel(chatModel)
    .withInputGuardrailClassesList("com.example.MyInputGuardrail")
    .withOutputGuardrailClassesList("com.example.MyOutputGuardrail1,com.example.MyOutputGuardrail2");

Agent safeAgent = new AgentWithoutMemory(configuration);
context.getRegistry().bind("safeAgent", safeAgent);

// Use the agent with guardrails
from("direct:agent-with-guardrails")
    .to("langchain4j-agent:safe?agent=#safeAgent")

The current version of the component returns a String as response. If the outputGuardrails extends JsonExtractorOutputGuardrail class, make sure to return a Json in String format.

Built-in Guardrails

The camel-langchain4j-agent-api module provides production-ready guardrails in the org.apache.camel.component.langchain4j.agent.api.guardrails package.

Available Input Guardrails
Guardrail Class Description

InputLengthGuardrail

Validates message length (min/max characters). Prevents excessively long inputs.

PiiDetectorGuardrail

Detects Personally Identifiable Information (email, phone, SSN, credit cards, IP addresses).

PromptInjectionGuardrail

Detects prompt injection attacks (role manipulation, jailbreaks, delimiter injection).

KeywordFilterGuardrail

Blocks messages containing specific keywords or patterns.

LanguageGuardrail

Validates the language/script of user messages. Can allow or block specific languages (English, Cyrillic, Chinese, Japanese, Korean, Arabic, Hebrew, Greek, Thai, Devanagari).

CodeInjectionGuardrail

Detects potential code injection attempts including shell commands, SQL injection, JavaScript, HTML/XSS, path traversal, command chaining, and template injection.

RegexPatternGuardrail

Flexible guardrail using custom regex patterns. Can define deny patterns (block if matched) and require patterns (must be present).

Available Output Guardrails
Guardrail Class Description

OutputLengthGuardrail

Validates response length with optional truncation support.

SensitiveDataOutputGuardrail

Detects and optionally redacts sensitive data (API keys, passwords, JWT tokens, AWS keys).

JsonFormatGuardrail

Validates JSON format, extracts JSON from text, and checks for required fields.

KeywordOutputFilterGuardrail

Blocks or redacts specific content in AI responses.

NotEmptyGuardrail

Ensures AI responses are not empty or contain only whitespace. Can optionally detect refusal patterns (e.g., "I cannot", "I’m unable to").

WordCountGuardrail

Validates the word count of AI responses. Can enforce minimum, maximum, or range constraints.

Quick Start with Default Guardrails

The Guardrails helper class provides convenient factory methods:

import org.apache.camel.component.langchain4j.agent.api.guardrails.Guardrails;

// Create agent with default security guardrails
AgentConfiguration configuration = new AgentConfiguration()
    .withChatModel(chatModel)
    .withInputGuardrailClasses(Guardrails.defaultInputGuardrails())
    .withOutputGuardrailClasses(Guardrails.defaultOutputGuardrails());

Agent secureAgent = new AgentWithoutMemory(configuration);
context.getRegistry().bind("secureAgent", secureAgent);

from("direct:secure-chat")
    .to("langchain4j-agent:chat?agent=#secureAgent");

The default guardrails include:

  • Input: InputLengthGuardrail, PiiDetectorGuardrail, PromptInjectionGuardrail

  • Output: OutputLengthGuardrail, SensitiveDataOutputGuardrail

Using the Fluent Builder

The Guardrails.configure() method provides a fluent API for building configurations:

import org.apache.camel.component.langchain4j.agent.api.guardrails.Guardrails;

AgentConfiguration configuration = Guardrails.configure()
    .withPiiDetection()
    .withPromptInjectionDetection()
    .withInputLengthValidation()
    .withSensitiveDataDetection()
    .withJsonFormatValidation()
    .build();

configuration.withChatModel(chatModel);

Agent agent = new AgentWithoutMemory(configuration);

Using Specific Guardrail Classes

You can specify exactly which guardrails to use:

import org.apache.camel.component.langchain4j.agent.api.guardrails.*;

AgentConfiguration configuration = new AgentConfiguration()
    .withChatModel(chatModel)
    .withInputGuardrailClasses(List.of(
        InputLengthGuardrail.class,
        PiiDetectorGuardrail.class,
        PromptInjectionGuardrail.class
    ))
    .withOutputGuardrailClasses(List.of(
        SensitiveDataOutputGuardrail.class,
        JsonFormatGuardrail.class
    ));

Guardrail Presets

The Guardrails class provides preset configurations for different security levels:

// Minimal protection (just length validation)
configuration.withInputGuardrailClasses(Guardrails.minimalInputGuardrails());

// Standard protection (length, PII, prompt injection)
configuration.withInputGuardrailClasses(Guardrails.defaultInputGuardrails());

// Strict protection (all input guardrails)
configuration.withInputGuardrailClasses(Guardrails.strictInputGuardrails());

Factory Methods for Individual Guardrails

The Guardrails class provides static factory methods to create guardrail instances:

// Input guardrails
InputLengthGuardrail lengthGuard = Guardrails.inputLength(5000);  // Max 5000 chars
PiiDetectorGuardrail piiGuard = Guardrails.piiDetector();
PromptInjectionGuardrail injectionGuard = Guardrails.promptInjectionStrict();
KeywordFilterGuardrail keywordGuard = Guardrails.keywordFilter("banned", "blocked");

// Output guardrails
OutputLengthGuardrail outputLength = Guardrails.outputLengthTruncating(10000);
SensitiveDataOutputGuardrail sensitiveData = Guardrails.sensitiveDataRedacting();
JsonFormatGuardrail jsonGuard = Guardrails.jsonFormatWithFields("name", "email");

Advanced Guardrail Configuration with Builders

Each guardrail provides a builder for custom configuration:

PII Detection Configuration
import org.apache.camel.component.langchain4j.agent.api.guardrails.PiiDetectorGuardrail;
import org.apache.camel.component.langchain4j.agent.api.guardrails.PiiDetectorGuardrail.PiiType;

// Detect only specific PII types
PiiDetectorGuardrail guardrail = PiiDetectorGuardrail.builder()
    .detectTypes(PiiType.EMAIL, PiiType.PHONE, PiiType.SSN)
    .blockOnDetection(true)
    .build();
Prompt Injection Detection Configuration
import org.apache.camel.component.langchain4j.agent.api.guardrails.PromptInjectionGuardrail;

// Strict mode: fail on any single pattern match
PromptInjectionGuardrail strictGuardrail = PromptInjectionGuardrail.strict();

// Custom patterns
PromptInjectionGuardrail customGuardrail = PromptInjectionGuardrail.builder()
    .strict(true)
    .addPattern(
        PromptInjectionGuardrail.InjectionCategory.JAILBREAK,
        Pattern.compile("(?i)custom\\s+attack\\s+pattern"))
    .build();
Sensitive Data Output Configuration
import org.apache.camel.component.langchain4j.agent.api.guardrails.SensitiveDataOutputGuardrail;
import org.apache.camel.component.langchain4j.agent.api.guardrails.SensitiveDataOutputGuardrail.*;

// Redact sensitive data instead of blocking
SensitiveDataOutputGuardrail guardrail = SensitiveDataOutputGuardrail.builder()
    .detectTypes(SensitiveDataType.API_KEY, SensitiveDataType.SECRET, SensitiveDataType.JWT)
    .action(Action.REDACT)
    .redactionText("***REDACTED***")
    .build();
JSON Format Validation Configuration
import org.apache.camel.component.langchain4j.agent.api.guardrails.JsonFormatGuardrail;

// Validate JSON with required fields
JsonFormatGuardrail guardrail = JsonFormatGuardrail.builder()
    .requireFields("id", "name", "email")
    .extractJson(true)      // Extract JSON from surrounding text
    .allowArray(false)      // Only allow objects, not arrays
    .build();
Keyword Filtering Configuration
import org.apache.camel.component.langchain4j.agent.api.guardrails.KeywordFilterGuardrail;
import org.apache.camel.component.langchain4j.agent.api.guardrails.KeywordOutputFilterGuardrail;

// Input keyword filter
KeywordFilterGuardrail inputFilter = KeywordFilterGuardrail.builder()
    .blockedWords("spam", "inappropriate", "banned")
    .blockedPattern("\\b(hack|exploit)\\b")
    .caseSensitive(false)
    .wholeWordMatch(true)
    .build();

// Output keyword filter with redaction
KeywordOutputFilterGuardrail outputFilter = KeywordOutputFilterGuardrail.builder()
    .blockedWords("confidential", "internal-only")
    .action(KeywordOutputFilterGuardrail.Action.REDACT)
    .redactionText("[REMOVED]")
    .build();
Language Validation Configuration
import org.apache.camel.component.langchain4j.agent.api.guardrails.LanguageGuardrail;
import org.apache.camel.component.langchain4j.agent.api.guardrails.LanguageGuardrail.Language;

// Allow only English input
LanguageGuardrail englishOnly = LanguageGuardrail.allowOnly(Language.ENGLISH);

// Allow English and Latin script languages (Spanish, French, German, etc.)
LanguageGuardrail latinLanguages = LanguageGuardrail.allowOnly(
    Language.ENGLISH, Language.LATIN_SCRIPT);

// Block specific languages
LanguageGuardrail blockCyrillic = LanguageGuardrail.block(Language.CYRILLIC);

// Custom configuration with mixed content control
LanguageGuardrail customLanguage = LanguageGuardrail.builder()
    .allowedLanguages(Language.ENGLISH, Language.LATIN_SCRIPT)
    .blockedLanguages(Language.CYRILLIC)
    .allowMixed(false)  // Don't allow mixed language content
    .build();
Code Injection Detection Configuration
import org.apache.camel.component.langchain4j.agent.api.guardrails.CodeInjectionGuardrail;
import org.apache.camel.component.langchain4j.agent.api.guardrails.CodeInjectionGuardrail.InjectionType;

// Default: detect all code injection types
CodeInjectionGuardrail defaultGuard = new CodeInjectionGuardrail();

// Strict mode: fail on any single pattern match
CodeInjectionGuardrail strictGuard = CodeInjectionGuardrail.strict();

// Detect only specific injection types
CodeInjectionGuardrail sqlAndShellOnly = CodeInjectionGuardrail.forTypes(
    InjectionType.SQL_INJECTION, InjectionType.SHELL_COMMAND);

// Custom configuration
CodeInjectionGuardrail customGuard = CodeInjectionGuardrail.builder()
    .detectTypes(InjectionType.SQL_INJECTION, InjectionType.JAVASCRIPT, InjectionType.PATH_TRAVERSAL)
    .strict(true)
    .build();
Regex Pattern Guardrail Configuration
import org.apache.camel.component.langchain4j.agent.api.guardrails.RegexPatternGuardrail;

// Block messages containing URLs
RegexPatternGuardrail noUrls = RegexPatternGuardrail.blocking(
    "https?://[^\\s]+", "URLs are not allowed in messages");

// Require messages to contain a ticket number
RegexPatternGuardrail requireTicket = RegexPatternGuardrail.requiring(
    "TICKET-\\d+", "Please include a ticket number (e.g., TICKET-123)");

// Complex configuration with multiple patterns
RegexPatternGuardrail customPatterns = RegexPatternGuardrail.builder()
    .denyPattern("https?://[^\\s]+", "URLs are not allowed")
    .denyPattern("\\b(password|secret)\\b", "Sensitive keywords are not allowed")
    .requirePattern("[A-Z]{2,4}-\\d+", "Please include a valid issue ID")
    .failOnFirstMatch(true)  // Stop checking after first failure
    .build();
Not Empty Guardrail Configuration
import org.apache.camel.component.langchain4j.agent.api.guardrails.NotEmptyGuardrail;

// Default: just ensure response is not empty
NotEmptyGuardrail notEmpty = new NotEmptyGuardrail();

// Also detect refusal patterns like "I cannot", "I'm unable to"
NotEmptyGuardrail withRefusalDetection = NotEmptyGuardrail.withRefusalDetection();

// Require minimum meaningful length
NotEmptyGuardrail minLength = NotEmptyGuardrail.withMinLength(50);

// Custom configuration
NotEmptyGuardrail customNotEmpty = new NotEmptyGuardrail(
    true,   // detectRefusals
    100     // minMeaningfulLength
);
Word Count Guardrail Configuration
import org.apache.camel.component.langchain4j.agent.api.guardrails.WordCountGuardrail;

// Require at least 10 words
WordCountGuardrail atLeast10 = WordCountGuardrail.atLeast(10);

// Limit to maximum 500 words
WordCountGuardrail atMost500 = WordCountGuardrail.atMost(500);

// Require between 50 and 200 words
WordCountGuardrail between = WordCountGuardrail.between(50, 200);

// Custom configuration
WordCountGuardrail custom = WordCountGuardrail.builder()
    .minWords(20)
    .maxWords(1000)
    .build();

Complete Example with Memory and Guardrails

import org.apache.camel.component.langchain4j.agent.api.*;
import org.apache.camel.component.langchain4j.agent.api.guardrails.*;
import dev.langchain4j.model.openai.OpenAiChatModel;
import dev.langchain4j.memory.chat.MessageWindowChatMemory;

public class SecureAgentRoute extends RouteBuilder {

    @Override
    public void configure() throws Exception {
        // Create chat model
        ChatModel chatModel = OpenAiChatModel.builder()
            .apiKey("{{openai.api.key}}")
            .modelName("gpt-4o")
            .build();

        // Create memory provider
        ChatMemoryProvider memoryProvider = memoryId ->
            MessageWindowChatMemory.withMaxMessages(20);

        // Create secure agent configuration
        AgentConfiguration configuration = new AgentConfiguration()
            .withChatModel(chatModel)
            .withChatMemoryProvider(memoryProvider)
            .withInputGuardrailClasses(Guardrails.defaultInputGuardrails())
            .withOutputGuardrailClasses(Guardrails.defaultOutputGuardrails());

        Agent secureAgent = new AgentWithMemory(configuration);
        getContext().getRegistry().bind("secureAgent", secureAgent);

        // Secure chat route with error handling
        from("direct:chat")
            .setHeader("CamelLangChain4jMemoryId", simple("${header.userId}"))
            .doTry()
                .to("langchain4j-agent:chat?agent=#secureAgent")
            .doCatch(dev.langchain4j.service.guardrail.GuardrailException.class)
                .log("Guardrail blocked request: ${exception.message}")
                .setBody(constant("Your message was blocked due to security policies."))
            .end();
    }
}

Spring Boot Configuration Example

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class AgentConfig {

    @Bean
    public ChatModel chatModel() {
        return OpenAiChatModel.builder()
            .apiKey(System.getenv("OPENAI_API_KEY"))
            .modelName("gpt-4o")
            .build();
    }

    @Bean("secureAgent")
    public Agent secureAgent(ChatModel chatModel) {
        AgentConfiguration config = new AgentConfiguration()
            .withChatModel(chatModel)
            .withInputGuardrailClasses(Guardrails.defaultInputGuardrails())
            .withOutputGuardrailClasses(Guardrails.defaultOutputGuardrails());

        return new AgentWithoutMemory(config);
    }
}

Guardrail Behavior Summary

Guardrail When Triggered Result

InputLengthGuardrail

Input too short/long

Blocks the request

PiiDetectorGuardrail

PII detected

Blocks the request

PromptInjectionGuardrail

Injection attempt detected

Blocks the request

KeywordFilterGuardrail

Blocked keyword found

Blocks the request

LanguageGuardrail

Disallowed language/script detected

Blocks the request

CodeInjectionGuardrail

Code injection pattern detected

Blocks the request

RegexPatternGuardrail

Deny pattern matched or require pattern missing

Blocks the request

OutputLengthGuardrail

Response too short/long

Retries LLM or truncates

SensitiveDataOutputGuardrail

Secrets in response

Blocks or redacts

JsonFormatGuardrail

Invalid JSON format

Retries LLM call

KeywordOutputFilterGuardrail

Blocked content in response

Blocks or redacts

NotEmptyGuardrail

Empty response or refusal detected

Retries LLM call

WordCountGuardrail

Word count outside allowed range

Retries LLM call

Multimodal Content Support

The LangChain4j Agent component supports multimodal content, allowing you to send images, PDFs, audio, video, and text files to AI models that support vision and document understanding capabilities.

Sending Multimodal Content via AiAgentBody

You can explicitly create an AiAgentBody with multimodal content:

// Load an image and create ImageContent
byte[] imageBytes = Files.readAllBytes(Path.of("image.png"));
String base64Image = Base64.getEncoder().encodeToString(imageBytes);
Image image = Image.builder()
    .base64Data(base64Image)
    .mimeType("image/png")
    .build();
ImageContent imageContent = ImageContent.from(image);

// Create request body with image content
AiAgentBody<ImageContent> body = new AiAgentBody<ImageContent>()
    .withUserMessage("What do you see in this image?")
    .withContent(imageContent);

String response = template.requestBody("direct:chat", body, String.class);

Automatic File Conversion from Camel Components

The agent component automatically converts files from various Camel components to multimodal content. This enables seamless integration with file-based sources.

Supported Input Types
Input Type Source Components MIME Type Detection

WrappedFile

file:, ftp:, sftp:, smb:

From file extension or headers

byte[]

aws2-s3:, azure-storage-blob:, google-storage:

From content type headers (required)

InputStream

Various streaming components

From content type headers (required)

Example: Processing Images from File Component
from("file:inbox/images?noop=true&include=.*\\.png")
    .setHeader("CamelLangChain4jAgentUserMessage", constant("Describe this image"))
    .to("langchain4j-agent:vision?agent=#visionAgent")
    .to("log:response");
Example: Processing Files from AWS S3
from("aws2-s3://my-bucket?prefix=images/&includeBody=true")
    .setHeader("CamelLangChain4jAgentUserMessage", constant("What do you see in this image?"))
    .to("langchain4j-agent:vision?agent=#visionAgent")
    .to("log:response");

When using byte[] or InputStream inputs, a MIME type header is required since the type cannot be auto-detected from the content. The component checks for MIME type in this priority order:

  1. CamelLangChain4jAgentMediaType header (highest priority - explicit override)

  2. CamelAwsS3ContentType header (from AWS S3)

  3. Content-Type header

  4. CamelFileContentType header (from file components)

Example: Overriding MIME Type
from("direct:process-file")
    .setHeader("CamelLangChain4jAgentUserMessage", constant("Analyze this document"))
    .setHeader("CamelLangChain4jAgentMediaType", constant("application/pdf"))
    .to("langchain4j-agent:analyzer?agent=#analyzerAgent");

Complete Multimodal Route Example

Here’s a complete example showing how to process images from a file system and send them to an AI agent for analysis:

// Create a vision-capable chat model
ChatModel chatModel = OpenAiChatModel.builder()
    .apiKey(apiKey)
    .modelName("gpt-4o")  // Vision-capable model
    .build();

// Create agent configuration
AgentConfiguration configuration = new AgentConfiguration()
    .withChatModel(chatModel);

Agent visionAgent = new AgentWithoutMemory(configuration);
context.getRegistry().bind("visionAgent", visionAgent);

// Route to process images
from("file:inbox/images?noop=true&include=.*\\.(png|jpg|jpeg)")
    .setHeader("CamelLangChain4jAgentUserMessage",
        constant("Describe what you see in this image. Be detailed but concise."))
    .to("langchain4j-agent:vision?agent=#visionAgent")
    .log("AI Response: ${body}")
    .to("file:outbox/descriptions");