AI with Java/Autonomous Agents

    Autonomous AI Agents

    Build AI systems that can reason, plan, and execute complex multi-step tasks independently. Agents go beyond simple Q&A—they take action in the real world.

    Autonomous agents are AI systems that can independently pursue goals by breaking them into subtasks, using tools, and iterating until the objective is achieved. Instead of asking "What's the weather?", an agent can "Plan my weekend trip to somewhere sunny, book the cheapest flight, and add it to my calendar"—handling all the steps automatically.

    With Spring AI, you can build agents that leverage function calling, memory, and reasoning patterns like ReAct and Chain-of-Thought to accomplish sophisticated tasks that would be impossible with simple prompt-response patterns.

    What Makes an Agent?

    Reasoning

    Breaks down complex goals into actionable steps

    Tool Use

    Invokes external APIs, databases, and services

    Iteration

    Loops until the goal is achieved or limits hit

    Observation

    Evaluates results and adjusts strategy

    Agent vs Chatbot

    Chatbot

    • • Single prompt → Single response
    • • User drives the conversation
    • • Limited to answering questions
    • • May call 1-2 functions per turn
    • • Stateless or simple memory

    Autonomous Agent

    • • Single goal → Many steps automatically
    • • Agent drives toward objective
    • • Takes actions and makes decisions
    • • Chains many function calls
    • • Rich memory and context tracking

    The ReAct Pattern

    ReAct (Reason + Act) is the most popular agent pattern. The model alternates between reasoning about what to do next and taking actions via tools.

    1

    Thought

    "I need to find flights to warm destinations first"

    2

    Action

    Call getWeather(["Miami", "Phoenix", "LA"])

    3

    Observation

    Phoenix is 95°F, Miami is 85°F, LA is 72°F

    4

    Thought

    "Phoenix is warmest. Now I'll search for flights."

    5

    Action

    Call searchFlights(destination: "Phoenix")

    ... continues until goal achieved ...

    Building an Agent with Spring AI

    Agent Loop Implementation

    Core pattern for an autonomous agent

    TravelPlannerAgent.java
    @ServicepublicclassTravelPlannerAgent{privatefinalChatClient chatClient;privatestaticfinalintMAX_ITERATIONS=10;publicTravelPlannerAgent(ChatClient.Builder builder,WeatherFunction weatherFunction,FlightSearchFunction flightFunction,CalendarFunction calendarFunction){this.chatClient = builder
    .defaultSystem("""
    You are a travel planning agent. Your goal is to help users
    plan trips by finding destinations, booking flights, and
    managing their calendar.
    Think step by step. After each action, evaluate the result
    and decide what to do next. When the goal is complete,
    respond with "TASK_COMPLETE:" followed by a summary.
    """).defaultFunctions(weatherFunction, flightFunction, calendarFunction).build();}publicAgentResultexecute(String userGoal){List<String> steps =newArrayList<>();String currentContext = userGoal;for(int i =0; i <MAX_ITERATIONS; i++){// Agent thinks and actsString response = chatClient.prompt().user(currentContext).call().content();
    steps.add("Step "+(i +1)+": "+ response);// Check if goal is completeif(response.contains("TASK_COMPLETE:")){returnnewAgentResult(true, steps,extractSummary(response));}// Update context for next iteration
    currentContext ="Previous result: "+ response +"\n\nContinue working toward the goal: "+ userGoal;}returnnewAgentResult(false, steps,"Max iterations reached");}}recordAgentResult(boolean success,List<String> steps,String summary){}

    Designing Agent Tools

    Agents are only as good as their tools. Well-designed tools have clear descriptions, handle errors gracefully, and return structured, actionable data.

    FlightSearchFunction.java
    @Component@JsonClassDescription("Search for available flights between cities")publicclassFlightSearchFunctionimplementsFunction<FlightQuery,FlightResults>{privatefinalFlightApiClient flightApi;@OverridepublicFlightResultsapply(FlightQuery query){try{List<Flight> flights = flightApi.search(
    query.origin(),
    query.destination(),
    query.departureDate());// Return structured data the agent can reason aboutreturnnewFlightResults(true,
    flights.size(),
    flights.stream().sorted(Comparator.comparing(Flight::getPrice)).limit(5).toList(),null);}catch(Exception e){// Agents need to know when things failreturnnewFlightResults(false,0,List.of(), e.getMessage());}}}recordFlightQuery(@JsonProperty(required =true, description ="Origin city or airport code")String origin,@JsonProperty(required =true, description ="Destination city or airport code")String destination,@JsonProperty(description ="Departure date in YYYY-MM-DD format")String departureDate
    ){}recordFlightResults(boolean success,int totalFound,List<Flight> topFlights,String error
    ){}

    Agent Memory Patterns

    Short-Term Memory

    Tracks the current task's context, actions taken, and observations. Cleared after each goal is complete.

    Java Example
    List<Message> scratchpad =newArrayList<>();
    scratchpad.add(newUserMessage(goal));
    scratchpad.add(newAssistantMessage(thought));
    scratchpad.add(newToolMessage(result));

    Long-Term Memory

    Persists user preferences, past interactions, and learned patterns across sessions using vector stores.

    Java Example
    // Store important facts
    vectorStore.add(newDocument("User prefers window seats",Map.of("type","preference")));// Retrieve relevant context
    vectorStore.similaritySearch(goal);

    Agent Safety & Guardrails

    Iteration Limits

    Always cap the agent loop (10-20 iterations max). Infinite loops are expensive and dangerous.

    Cost Controls

    Track token usage per run. Set budget limits and abort if exceeded.

    Action Approval

    Require human confirmation for high-stakes actions (payments, deletions, external comms).

    Sandboxing

    Restrict tool capabilities. An agent shouldn't have production write access during testing.

    Agent Use Cases

    Research Agents

    Gather information from multiple sources, synthesize findings, and produce reports.

    DevOps Agents

    Monitor systems, diagnose issues, and execute remediation playbooks automatically.

    Task Automation

    Handle multi-step workflows like onboarding, data migration, or report generation.

    Build Your First Agent

    Start with a simple ReAct loop and 2-3 tools. Add complexity as you learn. Remember: agents are powerful but require careful guardrails.