Google Gen AI llm event refactor

Author: amychisholm03

lib/llm-events-new/base.js

@@ -19,7 +19,7 @@ const { makeId } = require('../util/hashes')
  * @property {string} response.model Model name from response
  * @property {string} vendor Lowercased vendor name, e.g. "openai"
  * @property {string} ingest_source Always set to 'Node'
- * @property {boolean|undefined} error set to `true` if an error occurred during creation call, omitted if no error occurred
+ * @property {boolean|undefined} error Set to `true` if an error occurred during creation call, omitted if no error occurred
  */
 class LlmEvent {
   ingest_source = 'Node'
@@ -33,20 +33,24 @@ class LlmEvent {
    * @param {string} params.vendor Lowercase vendor name, e.g. "openai"
    * @param {string} params.responseModel Model name from response
    * @param {string} params.requestId ID from request/response headers
-   * @param {boolean} [params.error] set to `true` if an error occurred during creation call, omitted if no error occurred
+   * @param {boolean} [params.error] Set to `true` if an error occurred during creation call, omitted if no error occurred
    */
-  constructor({ agent, segment, transaction, vendor, responseModel, requestId, error = null }) {
+  constructor({ agent, segment, transaction, vendor, responseModel, requestId, error }) {
     this.id = makeId(36)
-    this.request_id = requestId
     this.span_id = segment?.id
     this.trace_id = transaction?.traceId
-    this['response.model'] = responseModel
     this.vendor = vendor
     this.metadata = agent
 
+    // Omit `error` property if no error occurred
     if (error === true) {
       this.error = error
     }
+
+    // If a certain attribute value is not accessible via instrumentation,
+    // it can be omitted from the event.
+    if (requestId) this.request_id = requestId
+    if (responseModel) this['response.model'] = responseModel
   }
 
   // eslint-disable-next-line accessor-pairs

lib/llm-events-new/chat-summary.js

@@ -45,8 +45,8 @@ class LlmChatCompletionSummary extends LlmEvent {
     this['request.max_tokens'] = maxTokens
     this['request.temperature'] = temperature
     this['response.number_of_messages'] = numMsgs
-    this['response.choices.finish_reason'] = finishReason
-    this['response.organization'] = responseOrg
+    if (finishReason) this['response.choices.finish_reason'] = finishReason
+    if (responseOrg) this['response.organization'] = responseOrg
     this.timestamp = segment.timer.start
     this.duration = segment.getDurationInMillis()
   }

lib/llm-events-new/embedding.js

@@ -33,9 +33,9 @@ class LlmEmbedding extends LlmEvent {
    */
   constructor({ agent, segment, transaction, requestId, requestInput, requestModel, responseModel, responseOrg, vendor, error }) {
     super({ agent, segment, requestId, responseModel, transaction, vendor, error })
-    this['request.model'] = requestModel
-    this['response.organization'] = responseOrg
-    this.duration = segment?.getDurationInMillis()
+    if (requestModel) this['request.model'] = requestModel
+    if (responseOrg) this['response.organization'] = responseOrg
+    this.duration = segment.getDurationInMillis()
 
     if (agent.config.ai_monitoring.record_content.enabled === true) {
       this.input = requestInput

lib/llm-events-new/google-genai/chat-message.js

@@ -0,0 +1,66 @@
+/*
+ * Copyright 2026 New Relic Corporation. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+const LlmChatCompletionMessage = require('../chat-message')
+const { getUsageTokens } = require('./utils')
+
+/**
+ * Encapsulates a Google Gen AI LlmChatCompletionMessage.
+ */
+class GoogleGenAiLlmChatCompletionMessage extends LlmChatCompletionMessage {
+  constructor({ agent,
+    segment,
+    transaction,
+    request = {},
+    response = {},
+    sequence = 0,
+    content, role,
+    completionId,
+    isResponse }) {
+    super({ agent,
+      segment,
+      transaction,
+      vendor: 'gemini',
+      sequence,
+      content,
+      role,
+      completionId,
+      isResponse,
+      responseModel: response?.modelVersion })
+
+    this.setTokenCount(agent, request, response)
+  }
+
+  setTokenCount(agent, request, response) {
+    const tokenCB = agent.llm?.tokenCountCallback
+
+    if (tokenCB) {
+      const promptContent = typeof request?.contents === 'string'
+        ? request?.contents
+        : request?.contents?.join(' ')
+
+      const responseContent = response?.candidates?.[0]?.content?.parts
+      const completionContent = responseContent?.map((content) => content.text).join(' ')
+
+      if (promptContent && completionContent) {
+        this.setTokenFromCallback(
+          {
+            tokenCB,
+            reqModel: request.model,
+            resModel: this['response.model'],
+            promptContent,
+            completionContent
+          }
+        )
+      }
+      return
+    }
+
+    const tokens = getUsageTokens(response)
+    this.setTokenInCompletionMessage(tokens)
+  }
+}
+
+module.exports = GoogleGenAiLlmChatCompletionMessage

lib/llm-events-new/google-genai/chat-summary.js

@@ -0,0 +1,67 @@
+/*
+ * Copyright 2026 New Relic Corporation. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+const LlmChatCompletionSummary = require('../chat-summary')
+const { getUsageTokens } = require('./utils')
+
+/**
+ * Encapsulates a Google Gen AI LlmChatCompletionSummary.
+ */
+class GoogleGenAiLlmChatCompletionSummary extends LlmChatCompletionSummary {
+  constructor({ agent, segment, transaction, request, response, error }) {
+    super({ agent,
+      segment,
+      transaction,
+      responseModel: response?.modelVersion,
+      requestModel: request?.model,
+      finishReason: response?.candidates?.[0]?.finishReason,
+      maxTokens: request.config?.maxOutputTokens,
+      temperature: request.config?.temperature,
+      vendor: 'gemini',
+      error })
+
+    let requestMessagesLength = 0
+    if (Array.isArray(request?.contents)) {
+      requestMessagesLength = request.contents.length
+    } else if (typeof request?.contents === 'string') {
+      requestMessagesLength = 1
+    }
+    this['response.number_of_messages'] = requestMessagesLength + (response?.candidates?.length || 0)
+
+    this.setTokens(agent, request, response)
+  }
+
+  setTokens(agent, request, response) {
+    const tokenCB = agent.llm?.tokenCountCallback
+
+    // Prefer callback for prompt and completion tokens; if unavailable, fall back to response data.
+    if (tokenCB) {
+      const promptContent = typeof request?.contents === 'string'
+        ? request?.contents
+        : request?.contents?.join(' ')
+
+      const responseContent = response?.candidates?.[0]?.content?.parts
+      const completionContent = responseContent?.map((content) => content.text).join(' ')
+
+      if (promptContent && completionContent) {
+        this.setTokenUsageFromCallback(
+          {
+            tokenCB,
+            reqModel: request.model,
+            resModel: this['response.model'],
+            promptContent,
+            completionContent
+          }
+        )
+      }
+      return
+    }
+
+    const tokens = getUsageTokens(response)
+    this.setTokensInResponse(tokens)
+  }
+}
+
+module.exports = GoogleGenAiLlmChatCompletionSummary

lib/llm-events-new/google-genai/embedding.js

@@ -0,0 +1,24 @@
+/*
+ * Copyright 2026 New Relic Corporation. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+const LlmEmbedding = require('../embedding')
+
+/**
+ * Encapsulates a Google Gen AI LlmEmbedding.
+ */
+class GoogleGenAiLlmEmbedding extends LlmEmbedding {
+  constructor({ agent, segment, transaction, request = {}, response = {}, error }) {
+    super({ agent,
+      segment,
+      transaction,
+      requestInput: request?.contents,
+      requestModel: request?.model,
+      responseModel: response?.modelVersion,
+      vendor: 'gemini',
+      error })
+  }
+}
+
+module.exports = GoogleGenAiLlmEmbedding

lib/llm-events-new/google-genai/index.js

@@ -0,0 +1,16 @@
+/*
+ * Copyright 2026 New Relic Corporation. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+'use strict'
+
+const LlmChatCompletionMessage = require('./chat-message')
+const LlmChatCompletionSummary = require('./chat-summary')
+const LlmEmbedding = require('./embedding')
+
+module.exports = {
+  LlmChatCompletionMessage,
+  LlmChatCompletionSummary,
+  LlmEmbedding
+}

lib/llm-events-new/google-genai/utils.js

@@ -0,0 +1,13 @@
+/*
+ * Copyright 2026 New Relic Corporation. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+function getUsageTokens(response) {
+  const promptTokens = Number(response?.usageMetadata?.promptTokenCount)
+  const completionTokens = Number(response?.usageMetadata?.candidatesTokenCount)
+  const totalTokens = Number(response?.usageMetadata?.totalTokenCount)
+  return { promptTokens, completionTokens, totalTokens }
+}
+
+module.exports = { getUsageTokens }

lib/llm-events/google-genai/embedding.js

@@ -7,12 +7,10 @@
 
 const LlmChatCompletionSummary = require('./chat-completion-summary')
 const LlmChatCompletionMessage = require('./chat-completion-message')
-const LlmEmbedding = require('./embedding')
 const LlmErrorMessage = require('../error-message')
 
 module.exports = {
   LlmChatCompletionMessage,
   LlmChatCompletionSummary,
-  LlmEmbedding,
   LlmErrorMessage
 }