Skip to content

refactor!: remove support for legacy transferToAgent, superseded by transfer_to_agent #939

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
copybara-service merged 1 commit into from
Mar 4, 2026
Merged

refactor!: remove support for legacy transferToAgent, superseded by transfer_to_agent #939

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
25 changes: 3 additions & 22 deletions core/src/main/java/com/google/adk/flows/llmflows/AgentTransfer.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -55,22 +55,17 @@ public Single<RequestProcessor.RequestProcessingResult> processRequest(
.appendInstructions(
ImmutableList.of(buildTargetAgentsInstructions(agent, transferTargets)));

// Note: this tool is not exposed to the LLM in GenerateContent request. It is there only to
// serve as a backwards-compatible instance for users who depend on the exact name of
// "transferToAgent".
builder.appendTools(ImmutableList.of(createTransferToAgentTool("legacyTransferToAgent")));

FunctionTool agentTransferTool = createTransferToAgentTool("transferToAgent");
FunctionTool agentTransferTool = createTransferToAgentTool();
agentTransferTool.processLlmRequest(builder, ToolContext.builder(context).build());
return Single.just(
RequestProcessor.RequestProcessingResult.create(builder.build(), ImmutableList.of()));
}

private FunctionTool createTransferToAgentTool(String methodName) {
private FunctionTool createTransferToAgentTool() {
Method transferToAgentMethod;
try {
transferToAgentMethod =
AgentTransfer.class.getMethod(methodName, String.class, ToolContext.class);
AgentTransfer.class.getMethod("transferToAgent", String.class, ToolContext.class);
} catch (NoSuchMethodException e) {
throw new IllegalStateException(e);
}
Expand Down Expand Up @@ -169,18 +164,4 @@ public static void transferToAgent(
EventActions eventActions = toolContext.eventActions();
toolContext.setActions(eventActions.toBuilder().transferToAgent(agentName).build());
}

/**
* Backwards compatible transferToAgent that uses camel-case naming instead of the ADK's
* snake_case convention.
*
* <p>It exists only to support users who already use literal "transferToAgent" function call to
* instruct ADK to transfer the question to another agent.
*/
@Schema(name = "transferToAgent")
public static void legacyTransferToAgent(
@Schema(name = "agentName") String agentName,
@Schema(optional = true) ToolContext toolContext) {
transferToAgent(agentName, toolContext);
}
}
8 changes: 1 addition & 7 deletions core/src/main/java/com/google/adk/flows/llmflows/BaseLlmFlow.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -577,13 +577,7 @@ public void onError(Throwable e) {
.get()
.content(event.content().get());
}
if (functionResponses.stream()
.anyMatch(
functionResponse ->
functionResponse
.name()
.orElse("")
.equals("transferToAgent"))
if (event.actions().transferToAgent().isPresent()
|| event.actions().endInvocation().orElse(false)) {
sendTask.dispose();
connection.close();
Expand Down
127 changes: 47 additions & 80 deletions core/src/test/java/com/google/adk/flows/llmflows/AgentTransferTest.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -24,12 +24,13 @@
import static com.google.common.truth.Truth.assertThat;

import com.google.adk.agents.InvocationContext;
import com.google.adk.agents.LiveRequest;
import com.google.adk.agents.LiveRequestQueue;
import com.google.adk.agents.LlmAgent;
import com.google.adk.agents.LoopAgent;
import com.google.adk.agents.RunConfig;
import com.google.adk.agents.SequentialAgent;
import com.google.adk.events.Event;
import com.google.adk.models.LlmRequest;
import com.google.adk.runner.InMemoryRunner;
import com.google.adk.runner.Runner;
import com.google.adk.sessions.Session;
Expand All @@ -44,6 +45,7 @@
import com.google.genai.types.Schema;
import io.reactivex.rxjava3.core.Flowable;
import io.reactivex.rxjava3.core.Single;
import io.reactivex.rxjava3.subscribers.TestSubscriber;
import java.util.List;
import java.util.Map;
import java.util.Optional;
Expand Down Expand Up @@ -97,6 +99,50 @@ public void exitLoopTool_exitsLoop() {
// TODO: b/413488103 - complete when LoopAgent is implemented.
}

@Test
public void runLive_transferToAgent_closesConnection() throws Exception {
// Arrange
Content transferCallContent = Content.fromParts(createTransferCallPart("sub_agent_1"));
Content response1 = Content.fromParts(Part.fromText("response1"));

TestLlm testLlm =
createTestLlm(
Flowable.just(createLlmResponse(transferCallContent)),
Flowable.just(createLlmResponse(response1)));

LlmAgent subAgent1 = createTestAgentBuilder(testLlm).name("sub_agent_1").build();
LlmAgent rootAgent =
createTestAgentBuilder(testLlm)
.name("root_agent")
.subAgents(ImmutableList.of(subAgent1))
.build();
InvocationContext invocationContext = createInvocationContext(rootAgent);

Runner runner = getRunnerAndCreateSession(rootAgent, invocationContext.session());
LiveRequestQueue liveRequestQueue = new LiveRequestQueue();

// Act
TestSubscriber<Event> testSubscriber =
runner
.runLive(invocationContext.session(), liveRequestQueue, RunConfig.builder().build())
.test();
liveRequestQueue.content(Content.fromParts(Part.fromText("hi")));
testSubscriber.await();

// Assert
testSubscriber.assertComplete();
assertThat(simplifyEvents(testSubscriber.values()))
.containsExactly(
"root_agent: FunctionCall(name=transfer_to_agent, args={agent_name=sub_agent_1})",
"root_agent: FunctionResponse(name=transfer_to_agent, response={})",
"sub_agent_1: response1")
.inOrder();

long closedConnectionsCount =
testLlm.getLiveRequestHistory().stream().filter(LiveRequest::shouldClose).count();
assertThat(closedConnectionsCount).isEqualTo(1);
}

@Test
public void testAutoToAuto() {
Content transferCallContent = Content.fromParts(createTransferCallPart("sub_agent_1"));
Expand Down Expand Up @@ -412,85 +458,6 @@ public void testAutoToLoop() {
assertThat(simplifyEvents(actualEvents)).containsExactly("root_agent: response5");
}

@Test
public void testLegacyTransferToAgent() {
Content transferCallContent =
Content.fromParts(
Part.fromFunctionCall("transferToAgent", ImmutableMap.of("agentName", "sub_agent_1")));
Content response1 = Content.fromParts(Part.fromText("response1"));
Content response2 = Content.fromParts(Part.fromText("response2"));

TestLlm testLlm =
createTestLlm(
Flowable.just(createLlmResponse(transferCallContent)),
Flowable.just(createLlmResponse(response1)),
Flowable.just(createLlmResponse(response2)));

LlmAgent subAgent1 = createTestAgentBuilder(testLlm).name("sub_agent_1").build();
LlmAgent rootAgent =
createTestAgentBuilder(testLlm)
.name("root_agent")
.subAgents(ImmutableList.of(subAgent1))
.build();
InvocationContext invocationContext = createInvocationContext(rootAgent);

Runner runner = getRunnerAndCreateSession(rootAgent, invocationContext.session());
List<Event> actualEvents = runRunner(runner, invocationContext);

assertThat(simplifyEvents(actualEvents))
.containsExactly(
"root_agent: FunctionCall(name=transferToAgent, args={agentName=sub_agent_1})",
"root_agent: FunctionResponse(name=transferToAgent, response={})",
"sub_agent_1: response1")
.inOrder();

actualEvents = runRunner(runner, invocationContext);

assertThat(simplifyEvents(actualEvents)).containsExactly("sub_agent_1: response2");
}

@Test
public void testAgentTransferDoesNotExposeLegacyTransferToAgent() {
Content transferCallContent =
Content.fromParts(
Part.fromFunctionCall("transferToAgent", ImmutableMap.of("agentName", "sub_agent_1")));
Content response1 = Content.fromParts(Part.fromText("response1"));
Content response2 = Content.fromParts(Part.fromText("response2"));
TestLlm testLlm =
createTestLlm(
Flowable.just(createLlmResponse(transferCallContent)),
Flowable.just(createLlmResponse(response1)),
Flowable.just(createLlmResponse(response2)));
LlmAgent subAgent1 = createTestAgentBuilder(testLlm).name("sub_agent_1").build();
LlmAgent rootAgent =
createTestAgentBuilder(testLlm)
.name("root_agent")
.subAgents(ImmutableList.of(subAgent1))
.build();
InvocationContext invocationContext = createInvocationContext(rootAgent);
AgentTransfer processor = new AgentTransfer();
LlmRequest request = LlmRequest.builder().build();

var processed = processor.processRequest(invocationContext, request);

assertThat(processed.blockingGet().updatedRequest().config().get().tools()).isPresent();
assertThat(processed.blockingGet().updatedRequest().config().get().tools().get()).hasSize(1);
assertThat(
processed
.blockingGet()
.updatedRequest()
.config()
.get()
.tools()
.get()
.get(0)
.functionDeclarations()
.get()
.get(0)
.name())
.hasValue("transfer_to_agent");
}

private Runner getRunnerAndCreateSession(LlmAgent agent, Session session) {
Runner runner = new InMemoryRunner(agent, session.appName());
// Ensure the session exists before running the agent.
Expand Down