Merge pull request #98 from langchain-ai/jacob/prompts

feat: Adds prompt pulling helpers
2026-08-24 12:22:55 -04:00 · 2026-03-25 09:01:29 -07:00
parent 3a1a72f559
commit 8cdc61ab86
19 changed files with 3637 additions and 0 deletions
@@ -0,0 +1,103 @@
+package com.langchain.smith.example
+
+import com.langchain.smith.client.okhttp.LangsmithOkHttpClient
+import com.langchain.smith.prompts.PromptClient
+import com.langchain.smith.prompts.convertToAnthropicParams
+import com.langchain.smith.prompts.convertToOpenAIParams
+
+/**
+ * Demonstrates pulling prompts from the LangSmith hub and converting them
+ * to OpenAI and Anthropic API formats.
+ *
+ * This example shows the simplified high-level prompt API, which mirrors
+ * the experience in the Python and TypeScript SDKs:
+ *
+ * ```java
+ * Prompt prompt = promptClient.pull("jacob/joke-generator");
+ * PromptValue formattedPrompt = prompt.invoke(Map.of("topic", "cats"));
+ * ChatCompletion completion = openai.chat().completions().create(
+ *     convertToOpenAIParams(formattedPrompt).model(ChatModel.GPT_4_1_MINI).build());
+ * ```
+ *
+ * Prerequisites:
+ * - `LANGSMITH_API_KEY`: Your LangSmith API key
+ * - A prompt must already exist in your LangSmith hub (e.g., "joke-generator").
+ *   You can create one via the UI or using the PromptManagementExample.
+ *
+ * Running:
+ * ```bash
+ * ./gradlew :langsmith-java-example:run -Pexample=PromptPull
+ * ```
+ */
+fun main() {
+    println("=== LangSmith Prompt Pull Example ===\n")
+
+    val client = LangsmithOkHttpClient.fromEnv()
+    val promptClient = PromptClient.create(client)
+
+    try {
+        // -------------------------------------------------------
+        // 1. Pull a prompt (like hub.pull() in TS/Python)
+        // -------------------------------------------------------
+        val owner = System.getenv("LANGSMITH_OWNER")?.takeIf { it.isNotEmpty() } ?: "-"
+        val promptIdentifier = "$owner/joke-generator"
+
+        println("1. Pulling prompt: '$promptIdentifier'")
+        val prompt = promptClient.pull(promptIdentifier)
+        println("   ✓ Pulled prompt (commit: ${prompt.commitHash})")
+        println("   ✓ Input variables: ${prompt.inputVariables}")
+        if (prompt.hasOutputSchema()) {
+            println("   ✓ Has structured output schema")
+        }
+        println()
+
+        // -------------------------------------------------------
+        // 2. Invoke with variables (like prompt.invoke() in TS/Python)
+        // -------------------------------------------------------
+        println("2. Invoking prompt with topic='cats'...")
+        val formattedPrompt = prompt.invoke(mapOf("topic" to "cats"))
+        println("   ✓ Formatted ${formattedPrompt.messages.size} message(s):")
+        for (msg in formattedPrompt.messages) {
+            println("     [${msg.role}] ${msg.template}")
+        }
+        println()
+
+        // -------------------------------------------------------
+        // 3. Convert to OpenAI format
+        // -------------------------------------------------------
+        println("3. Use with OpenAI:")
+        println("   // ChatCompletion completion = openai.chat().completions().create(")
+        println("   //     convertToOpenAIParams(formattedPrompt)")
+        println("   //         .model(ChatModel.GPT_4_1_MINI)")
+        println("   //         .build());")
+        println()
+
+        // -------------------------------------------------------
+        // 4. Convert to Anthropic format
+        // -------------------------------------------------------
+        println("4. Use with Anthropic:")
+        println("   // Message message = anthropic.messages().create(")
+        println("   //     convertToAnthropicParams(formattedPrompt)")
+        println("   //         .model(Model.CLAUDE_SONNET_4_6)")
+        println("   //         .maxTokens(1024)")
+        println("   //         .build());")
+        println()
+
+        // -------------------------------------------------------
+        // Summary
+        // -------------------------------------------------------
+        println("=== Summary ===")
+        println("✓ Pulled prompt from hub")
+        println("✓ Invoked with variables (${formattedPrompt.messages.size} messages)")
+        if (formattedPrompt.hasOutputSchema()) {
+            println("✓ Includes structured output schema")
+        }
+
+    } catch (e: Exception) {
+        System.err.println("\nError: ${e.message}")
+        e.printStackTrace()
+        System.exit(1)
+    } finally {
+        client.close()
+    }
+}