[google-adk-spring-ai] SpringAI beans are never auto-configured: @ConditionalOnBean(ChatModel) is evaluated before Spring AI model auto-configurations (missing ordering declaration)

Environment

Minimal reproduction

pom.xml (relevant parts):

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>4.0.2</version>
</parent>

<properties>
    <java.version>25</java.version>
    <spring-ai.version>2.0.1</spring-ai.version>
    <adk.version>1.9.0</adk.version>
</properties>

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter</artifactId>
    </dependency>
    <dependency>
        <groupId>com.google.adk</groupId>
        <artifactId>google-adk</artifactId>
        <version>${adk.version}</version>
    </dependency>
    <dependency>
        <groupId>com.google.adk</groupId>
        <artifactId>google-adk-spring-ai</artifactId>
        <version>${adk.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.ai</groupId>
        <artifactId>spring-ai-starter-model-openai</artifactId>
    </dependency>
</dependencies>

<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework.ai</groupId>
            <artifactId>spring-ai-bom</artifactId>
            <version>${spring-ai.version}</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

Application.java:

@SpringBootApplication
public class DemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }

    @Bean
    LlmAgent agent(SpringAI springAI) {
        return LlmAgent.builder()
                .name("demo-agent")
                .model(springAI)
                .instruction("You are a helpful assistant.")
                .build();
    }
}

application.yaml (dummy values are enough — the failure happens at bean-definition processing, before any remote call):

spring:
  ai:
    openai:
      base-url: https://api.openai.com
      api-key: dummy
      chat:
        model: gpt-4o-mini

Run: mvn spring-boot:run

Actual behavior

Application fails to start:

***************************
APPLICATION FAILED TO START
***************************

Description:

Parameter 0 of method agent in com.example.demo.DemoApplication required a bean
of type 'com.google.adk.models.springai.SpringAI' that could not be found.

Action:

Consider defining a bean of type 'com.google.adk.models.springai.SpringAI' in your configuration.

Running with --debug shows the root cause — the OpenAI ChatModel bean definition is registered, but SpringAIAutoConfiguration is processed before it, so all three SpringAI @Bean methods are skipped:

OpenAiChatAutoConfiguration matched:
   - @ConditionalOnProperty (spring.ai.model.chat=openai) matched
OpenAiChatAutoConfiguration#openAiChatModel matched:
   - @ConditionalOnMissingBean ... did not find any beans (OnBeanCondition)

SpringAIAutoConfiguration#springAIWithBothModels:
   Did not match:
      - @ConditionalOnBean (types: ...ChatModel, ...StreamingChatModel) did not find any beans
SpringAIAutoConfiguration#springAIWithChatModel:
   Did not match:
      - @ConditionalOnBean (types: ...ChatModel) did not find any beans of type ...ChatModel (OnBeanCondition)
SpringAIAutoConfiguration#springAIWithStreamingModel:
   Did not match:
      - @ConditionalOnBean (types: ...StreamingChatModel) did not find any beans

Note springAIEmbedding has the same problem (@ConditionalOnBean(EmbeddingModel.class)) — it fails silently (no bean, no error), which makes it even harder to notice.

Expected behavior

SpringAIAutoConfiguration registers a SpringAI bean whenever a ChatModel (and/or StreamingChatModel) is defined by Spring AI model auto-configurations, regardless of which provider starter is used.

Root cause

SpringAIAutoConfiguration guards its @Bean methods with @ConditionalOnBean(...), but declares no ordering relative to the auto-configurations that may provide those beans. Per the Spring Boot reference documentation, the result of @ConditionalOnBean depends on what has been processed so far, so an auto-configuration relying on it must be ordered after the configurations that register the matched beans.

google-adk-spring-ai 1.9.0 is built against Spring AI 2.x / Boot 4 (its POM depends on spring-ai-model:2.0.1 and spring-boot-autoconfigure:4.0.2), and since it compiles only against spring-ai-model (no provider modules), the Class-based after = ... attribute is not usable here — the string-based afterName attribute exists exactly for this case (non-existent class names are silently ignored by the sorter).

Suggested fix

Add an afterName list covering the Spring AI model auto-configurations, mirroring what Spring AI 1.x's own ChatClientAutoConfiguration did for the identical scenario (@ConditionalOnBean(ChatModel) with an unpredictable provider):

-@AutoConfiguration
+@AutoConfiguration(afterName = {
+    "org.springframework.ai.model.openai.autoconfigure.OpenAiChatAutoConfiguration",
+    "org.springframework.ai.model.openai.autoconfigure.OpenAiEmbeddingAutoConfiguration",
+    // remaining Spring AI 2.x model auto-configurations, e.g.:
+    // org.springframework.ai.model.anthropic.autoconfigure.AnthropicChatAutoConfiguration
+    // org.springframework.ai.model.ollama.autoconfigure.OllamaChatAutoConfiguration
+    // ... (package pattern: org.springframework.ai.model.<provider>.autoconfigure.*)
+})
 @ConditionalOnClass({SpringAI.class, ChatModel.class})
 @ConditionalOnProperty(prefix = "adk.spring-ai.auto-configuration", name = "enabled",
     havingValue = "true", matchIfMissing = true)
 @EnableConfigurationProperties({SpringAIProperties.class})
 public class SpringAIAutoConfiguration {

(Verified against Spring AI 2.0.1: org.springframework.ai.model.openai.autoconfigure.OpenAiChatAutoConfiguration / OpenAiEmbeddingAutoConfiguration. The other provider names above follow the 2.x package pattern and should be double-checked against the current source.)

An alternative design — the one Spring AI 2.0 itself adopted — is to drop the @ConditionalOnBean guards entirely and take ChatModel/StreamingChatModel as @Bean method parameters, which removes the ordering sensitivity altogether. The afterName fix is the smaller, backward-compatible change, though.

Workaround (for users on 1.9.0)

Define the SpringAI bean in application code — user-defined beans are processed before auto-configurations, and ADK's @ConditionalOnMissingBean(SpringAI.class) then backs off:

@Bean
SpringAI springAI(ChatModel chatModel) {
    return new SpringAI(chatModel, "gpt-4o-mini");
}

This works with any provider (it consumes the ChatModel abstraction), but every project using ADK + Spring AI has to copy it, so it is not a substitute for the upstream fix.

References

• Spring Boot reference — Creating your own auto-configuration / condition annotations: ordering matters for @ConditionalOnBean
• Spring AI 1.x ChatClientAutoConfiguration: same pattern solved with afterName over all provider auto-configurations
• Spring AI 2.0.1 ChatClientAutoConfiguration: same problem avoided via @Bean parameter injection instead of @ConditionalOnBean