Add temporal-tool-registry module with AgenticSession support

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: lex00

gradle/linting.gradle

@@ -9,7 +9,7 @@ subprojects {
             target 'src/*/java/**/*.java'
             targetExclude '**/generated/*'
             targetExclude '**/.idea/**'
-            googleJavaFormat('1.24.0')
+            googleJavaFormat('1.25.2')
         }
 
         kotlin {

settings.gradle

@@ -5,6 +5,7 @@ include 'temporal-sdk'
 include 'temporal-testing'
 include 'temporal-test-server'
 include 'temporal-opentracing'
+include 'temporal-tool-registry'
 include 'temporal-kotlin'
 include 'temporal-spring-boot-autoconfigure'
 include 'temporal-spring-boot-starter'

temporal-tool-registry/README.md

@@ -0,0 +1,202 @@
+# temporal-tool-registry
+
+LLM tool-calling primitives for Temporal activities — define tools once, use with
+Anthropic or OpenAI.
+
+## Before you start
+
+A Temporal Activity is a function that Temporal monitors and retries automatically on failure. Temporal streams progress between retries via heartbeats — that's the mechanism `AgenticSession` uses to resume a crashed LLM conversation mid-turn.
+
+`ToolRegistry.runToolLoop` works standalone in any function — no Temporal server needed. Add `AgenticSession` only when you need crash-safe resume inside a Temporal activity.
+
+`AgenticSession` requires a running Temporal worker — it reads and writes heartbeat state from the active activity context. Use `ToolRegistry.runToolLoop` standalone for scripts, one-off jobs, or any code that runs outside a Temporal worker.
+
+New to Temporal? → https://docs.temporal.io/develop
+
+## Install
+
+Add to your `build.gradle`:
+
+```groovy
+dependencies {
+    // Replace VERSION with the latest release from https://search.maven.org
+    implementation 'io.temporal:temporal-tool-registry:VERSION'
+    // Add only the LLM SDK(s) you use:
+    implementation 'com.anthropic:anthropic-java:VERSION'  // Anthropic
+    implementation 'com.openai:openai-java:VERSION'        // OpenAI
+}
+```
+
+## Quickstart
+
+Tool definitions use [JSON Schema](https://json-schema.org/understanding-json-schema/) for `inputSchema`. The quickstart uses a single string field; for richer schemas refer to the JSON Schema docs.
+
+```java
+import io.temporal.toolregistry.*;
+
+@ActivityMethod
+public List<String> analyze(String prompt) throws Exception {
+    List<String> issues = new ArrayList<>();
+    ToolRegistry registry = new ToolRegistry();
+    registry.register(
+        ToolDefinition.builder()
+            .name("flag_issue")
+            .description("Flag a problem found in the analysis")
+            .inputSchema(Map.of(
+                "type", "object",
+                "properties", Map.of("description", Map.of("type", "string")),
+                "required", List.of("description")))
+            .build(),
+        (Map<String, Object> input) -> {
+            issues.add((String) input.get("description"));
+            return "recorded"; // this string is sent back to the LLM as the tool result
+        });
+
+    AnthropicConfig cfg = AnthropicConfig.builder()
+        .apiKey(System.getenv("ANTHROPIC_API_KEY"))
+        .build();
+    Provider provider = new AnthropicProvider(cfg, registry,
+        "You are a code reviewer. Call flag_issue for each problem you find.");
+
+    ToolRegistry.runToolLoop(provider, registry, "" /* system prompt: "" defers to provider default */, prompt);
+    return issues;
+}
+```
+
+### Selecting a model
+
+The default model is `"claude-sonnet-4-6"` (Anthropic) or `"gpt-4o"` (OpenAI). Override with the `model()` builder method:
+
+```java
+AnthropicConfig cfg = AnthropicConfig.builder()
+    .apiKey(System.getenv("ANTHROPIC_API_KEY"))
+    .model("claude-3-5-sonnet-20241022")
+    .build();
+```
+
+Model IDs are defined by the provider — see Anthropic or OpenAI docs for current names.
+
+### OpenAI
+
+```java
+OpenAIConfig cfg = OpenAIConfig.builder()
+    .apiKey(System.getenv("OPENAI_API_KEY"))
+    .build();
+Provider provider = new OpenAIProvider(cfg, registry, "your system prompt");
+ToolRegistry.runToolLoop(provider, registry, "" /* system prompt: "" defers to provider default */, prompt);
+```
+
+## Crash-safe agentic sessions
+
+For multi-turn LLM conversations that must survive activity retries, use
+`AgenticSession.runWithSession`. It saves conversation history via
+`Activity.getExecutionContext().heartbeat()` on every turn and restores it on retry.
+
+```java
+@ActivityMethod
+public List<Object> longAnalysis(String prompt) throws Exception {
+    List<Object> issues = new ArrayList<>();
+
+    AgenticSession.runWithSession(session -> {
+        ToolRegistry registry = new ToolRegistry();
+        registry.register(
+            ToolDefinition.builder().name("flag").description("...").inputSchema(Map.of("type", "object")).build(),
+            input -> { session.addIssue(input); return "ok"; /* sent back to LLM */ });
+
+        AnthropicConfig cfg = AnthropicConfig.builder()
+            .apiKey(System.getenv("ANTHROPIC_API_KEY")).build();
+        Provider provider = new AnthropicProvider(cfg, registry, "your system prompt");
+
+        session.runToolLoop(provider, registry, "your system prompt", prompt);
+        issues.addAll(session.getIssues()); // capture after loop completes
+    });
+
+    return issues;
+}
+```
+
+## Testing without an API key
+
+```java
+import io.temporal.toolregistry.testing.*;
+
+@Test
+public void testAnalyze() throws Exception {
+    ToolRegistry registry = new ToolRegistry();
+    registry.register(
+        ToolDefinition.builder().name("flag").description("d")
+            .inputSchema(Map.of("type", "object")).build(),
+        input -> "ok");
+
+    MockProvider provider = new MockProvider(
+        MockResponse.toolCall("flag", Map.of("description", "stale API")),
+        MockResponse.done("analysis complete"));
+
+    List<Map<String, Object>> msgs =
+        ToolRegistry.runToolLoop(provider, registry, "sys", "analyze");
+    assertTrue(msgs.size() > 2);
+}
+```
+
+## Integration testing with real providers
+
+To run the integration tests against live Anthropic and OpenAI APIs:
+
+```bash
+RUN_INTEGRATION_TESTS=1 \
+  ANTHROPIC_API_KEY=sk-ant-... \
+  OPENAI_API_KEY=sk-proj-... \
+  ./gradlew test --tests "*.ToolRegistryTest.testIntegration*"
+```
+
+Tests skip automatically when `RUN_INTEGRATION_TESTS` is unset. Real API calls
+incur billing — expect a few cents per full test run.
+
+## Storing application results
+
+`session.getIssues()` accumulates application-level
+results during the tool loop. Elements are serialized to JSON inside each heartbeat
+checkpoint — they must be plain maps/dicts with JSON-serializable values. A non-serializable
+value raises a non-retryable `ApplicationError` at heartbeat time rather than silently
+losing data on the next retry.
+
+### Storing typed results
+
+Convert your domain type to a plain dict at the tool-call site and back after the session:
+
+```java
+record Issue(String type, String file) {}
+
+// Inside tool handler:
+session.addIssue(Map.of("type", "smell", "file", "Foo.java"));
+
+// After session (using Jackson for convenient mapping):
+// requires jackson-databind in your build.gradle:
+// implementation 'com.fasterxml.jackson.core:jackson-databind:VERSION'
+ObjectMapper mapper = new ObjectMapper();
+List<Issue> issues = session.getIssues().stream()
+    .map(m -> mapper.convertValue(m, Issue.class))
+    .toList();
+```
+
+## Per-turn LLM timeout
+
+Individual LLM calls inside the tool loop are unbounded by default. A hung HTTP
+connection holds the activity open until Temporal's `ScheduleToCloseTimeout`
+fires — potentially many minutes. Set a per-turn timeout on the provider client:
+
+```java
+AnthropicConfig cfg = AnthropicConfig.builder()
+    .apiKey(System.getenv("ANTHROPIC_API_KEY"))
+    .timeout(Duration.ofSeconds(30))
+    .build();
+Provider provider = new AnthropicProvider(cfg, registry, "your system prompt");
+// provider now enforces 30s per turn
+```
+
+Recommended timeouts:
+
+| Model type | Recommended |
+|---|---|
+| Standard (Claude 3.x, GPT-4o) | 30 s |
+| Reasoning (o1, o3, extended thinking) | 300 s |

temporal-tool-registry/build.gradle

@@ -0,0 +1,34 @@
+description = '''Temporal Java SDK Tool Registry - LLM tool-calling primitives for Temporal activities'''
+
+// Both Anthropic and OpenAI Java SDKs require Java 11+, so this module targets Java 11.
+// The core SDK supports Java 8+, but this contrib module is explicitly Java 11+.
+afterEvaluate {
+    compileJava.options.compilerArgs.removeAll { it == '8' }
+    compileJava.options.compilerArgs.removeAll { it == '--release' }
+    compileJava.options.compilerArgs.addAll(['--release', '11'])
+
+    compileTestJava.options.compilerArgs.removeAll { it == '8' }
+    compileTestJava.options.compilerArgs.removeAll { it == '--release' }
+    compileTestJava.options.compilerArgs.addAll(['--release', '11'])
+}
+
+ext {
+    anthropicVersion = '2.24.0'  // com.anthropic:anthropic-java
+    openaiVersion    = '4.31.0'  // com.openai:openai-java
+}
+
+dependencies {
+    // Not bundled — consumers provide temporal-sdk themselves, just like temporal-opentracing.
+    compileOnly project(':temporal-sdk')
+
+    // LLM providers are optional compile-time deps; users add only what they use.
+    compileOnly "com.anthropic:anthropic-java:$anthropicVersion"
+    compileOnly "com.openai:openai-java:$openaiVersion"
+
+    testImplementation project(':temporal-testing')
+    testImplementation "junit:junit:${junitVersion}"
+    testImplementation "org.mockito:mockito-core:${mockitoVersion}"
+    testImplementation "com.anthropic:anthropic-java:$anthropicVersion"
+    testImplementation "com.openai:openai-java:$openaiVersion"
+    testRuntimeOnly "ch.qos.logback:logback-classic:${logbackVersion}"
+}