Switching Providers - Pollack AI Lab

The Problem

You want to run the same agent task with different providers without changing your Java code.

Solution: Maven Profiles

Define one Maven profile per provider. Each profile puts a different starter on the classpath. Your Java code uses only the portable AgentClient API.

1. Define Profiles in pom.xml

<profiles>
    <profile>
        <id>claude</id>
        <activation>
            <activeByDefault>true</activeByDefault>
        </activation>
        <dependencies>
            <dependency>
                <groupId>io.github.markpollack</groupId>
                <artifactId>agent-starter-claude</artifactId>
                <version>${agent-client.version}</version>
            </dependency>
        </dependencies>
    </profile>
    <profile>
        <id>codex</id>
        <dependencies>
            <dependency>
                <groupId>io.github.markpollack</groupId>
                <artifactId>agent-starter-codex</artifactId>
                <version>${agent-client.version}</version>
            </dependency>
        </dependencies>
    </profile>
    <profile>
        <id>gemini</id>
        <dependencies>
            <dependency>
                <groupId>io.github.markpollack</groupId>
                <artifactId>agent-starter-gemini</artifactId>
                <version>${agent-client.version}</version>
            </dependency>
        </dependencies>
    </profile>
</profiles>

2. Add Per-Provider Configuration

Create profile-specific YAML files alongside your main application.yml:

application-claude.yml
application-codex.yml
application-gemini.yml

agent-client:
  claude:
    model: claude-sonnet-4-5
    yolo: true

agent-client:
  codex:
    model: gpt-5-codex
    full-auto: true

agent-client:
  gemini:
    model: gemini-2.5-flash
    yolo: true

Activate the matching Spring profile in your main application.yml:

spring:
  profiles:
    active: claude   # Matches the Maven profile

3. Run with a Specific Provider

# Claude (default profile)
./mvnw spring-boot:run

# Codex
./mvnw spring-boot:run -Pcodex -P'!claude' \
  -Dspring-boot.run.arguments="--spring.profiles.active=codex"

# Gemini
./mvnw spring-boot:run -Pgemini -P'!claude' \
  -Dspring-boot.run.arguments="--spring.profiles.active=gemini"

Use -P'!claude' to deactivate the default Claude profile when switching to another provider. Only one provider starter should be on the classpath.

Your Java Code Stays the Same

The key design principle: your Java code never imports provider-specific classes. It only uses:

AgentClient / AgentClient.Builder
AgentClientResponse
AgentOptions (for portable options)

Provider selection happens entirely through Maven profiles and Spring configuration.

Working Example

See samples/create-file-multi-provider for a complete working example, or the agent-client-tutorial for progressive examples.

​The Problem

​Solution: Maven Profiles

​1. Define Profiles in pom.xml

​2. Add Per-Provider Configuration

​3. Run with a Specific Provider

​Your Java Code Stays the Same

​Working Example

The Problem

Solution: Maven Profiles

1. Define Profiles in pom.xml

2. Add Per-Provider Configuration

3. Run with a Specific Provider

Your Java Code Stays the Same

Working Example