1 files changed, 191 insertions, 0 deletions
diff --git a/packages/core/src/telemetry/loggers.ts b/packages/core/src/telemetry/loggers.ts
new file mode 100644
index 00000000..ccab12ff
--- /dev/null
+++ b/packages/core/src/telemetry/loggers.ts
@@ -0,0 +1,191 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { logs, LogRecord, LogAttributes } from '@opentelemetry/api-logs';
+import { SemanticAttributes } from '@opentelemetry/semantic-conventions';
+import { Config } from '../config/config.js';
+import {
+  EVENT_API_ERROR,
+  EVENT_API_REQUEST,
+  EVENT_API_RESPONSE,
+  EVENT_CLI_CONFIG,
+  EVENT_TOOL_CALL,
+  EVENT_USER_PROMPT,
+  SERVICE_NAME,
+} from './constants.js';
+import {
+  ApiErrorEvent,
+  ApiRequestEvent,
+  ApiResponseEvent,
+  ToolCallEvent,
+  UserPromptEvent,
+} from './types.js';
+import {
+  recordApiErrorMetrics,
+  recordApiRequestMetrics,
+  recordApiResponseMetrics,
+  recordToolCallMetrics,
+} from './metrics.js';
+import { isTelemetrySdkInitialized } from './sdk.js';
+
+const shouldLogUserPrompts = (config: Config): boolean =>
+  config.getTelemetryLogUserPromptsEnabled() ?? false;
+
+export function logCliConfiguration(config: Config): void {
+  if (!isTelemetrySdkInitialized()) return;
+
+  const attributes: LogAttributes = {
+    'event.name': EVENT_CLI_CONFIG,
+    'event.timestamp': new Date().toISOString(),
+    model: config.getModel(),
+    sandbox_enabled:
+      typeof config.getSandbox() === 'string' ? true : config.getSandbox(),
+    core_tools_enabled: (config.getCoreTools() ?? []).join(','),
+    approval_mode: config.getApprovalMode(),
+    vertex_ai_enabled: config.getVertexAI() ?? false,
+    log_user_prompts_enabled: config.getTelemetryLogUserPromptsEnabled(),
+    file_filtering_respect_git_ignore:
+      config.getFileFilteringRespectGitIgnore(),
+    file_filtering_allow_build_artifacts:
+      config.getFileFilteringAllowBuildArtifacts(),
+  };
+  const logger = logs.getLogger(SERVICE_NAME);
+  const logRecord: LogRecord = {
+    body: 'CLI configuration loaded.',
+    attributes,
+  };
+  logger.emit(logRecord);
+}
+
+export function logUserPrompt(
+  config: Config,
+  event: Omit<UserPromptEvent, 'event.name' | 'event.timestamp' | 'prompt'> & {
+    prompt: string;
+  },
+): void {
+  if (!isTelemetrySdkInitialized()) return;
+  const { prompt, ...restOfEventArgs } = event;
+  const attributes: LogAttributes = {
+    ...restOfEventArgs,
+    'event.name': EVENT_USER_PROMPT,
+    'event.timestamp': new Date().toISOString(),
+  };
+  if (shouldLogUserPrompts(config)) {
+    attributes.prompt = prompt;
+  }
+  const logger = logs.getLogger(SERVICE_NAME);
+  const logRecord: LogRecord = {
+    body: `User prompt. Length: ${event.prompt_char_count}`,
+    attributes,
+  };
+  logger.emit(logRecord);
+}
+
+export function logToolCall(
+  event: Omit<ToolCallEvent, 'event.name' | 'event.timestamp'>,
+): void {
+  if (!isTelemetrySdkInitialized()) return;
+  const attributes: LogAttributes = {
+    ...event,
+    'event.name': EVENT_TOOL_CALL,
+    'event.timestamp': new Date().toISOString(),
+    function_args: JSON.stringify(event.function_args),
+  };
+  if (event.error) {
+    attributes['error.message'] = event.error;
+    if (event.error_type) {
+      attributes['error.type'] = event.error_type;
+    }
+  }
+  const logger = logs.getLogger(SERVICE_NAME);
+  const logRecord: LogRecord = {
+    body: `Tool call: ${event.function_name}. Success: ${event.success}. Duration: ${event.duration_ms}ms.`,
+    attributes,
+  };
+  logger.emit(logRecord);
+  recordToolCallMetrics(event.function_name, event.duration_ms, event.success);
+}
+
+export function logApiRequest(
+  event: Omit<ApiRequestEvent, 'event.name' | 'event.timestamp'>,
+): void {
+  if (!isTelemetrySdkInitialized()) return;
+  const attributes: LogAttributes = {
+    ...event,
+    'event.name': EVENT_API_REQUEST,
+    'event.timestamp': new Date().toISOString(),
+  };
+  const logger = logs.getLogger(SERVICE_NAME);
+  const logRecord: LogRecord = {
+    body: `API request to ${event.model}. Tokens: ${event.prompt_token_count}.`,
+    attributes,
+  };
+  logger.emit(logRecord);
+  recordApiRequestMetrics(event.model, event.prompt_token_count);
+}
+
+export function logApiError(
+  event: Omit<ApiErrorEvent, 'event.name' | 'event.timestamp'>,
+): void {
+  if (!isTelemetrySdkInitialized()) return;
+  const attributes: LogAttributes = {
+    ...event,
+    'event.name': EVENT_API_ERROR,
+    'event.timestamp': new Date().toISOString(),
+    ['error.message']: event.error,
+  };
+
+  if (event.error_type) {
+    attributes['error.type'] = event.error_type;
+  }
+  if (typeof event.status_code === 'number') {
+    attributes[SemanticAttributes.HTTP_STATUS_CODE] = event.status_code;
+  }
+
+  const logger = logs.getLogger(SERVICE_NAME);
+  const logRecord: LogRecord = {
+    body: `API error for ${event.model}. Error: ${event.error}. Duration: ${event.duration_ms}ms.`,
+    attributes,
+  };
+  logger.emit(logRecord);
+  recordApiErrorMetrics(
+    event.model,
+    event.duration_ms,
+    event.status_code,
+    event.error_type,
+  );
+}
+
+export function logApiResponse(
+  event: Omit<ApiResponseEvent, 'event.name' | 'event.timestamp'>,
+): void {
+  if (!isTelemetrySdkInitialized()) return;
+  const attributes: LogAttributes = {
+    ...event,
+    'event.name': EVENT_API_RESPONSE,
+    'event.timestamp': new Date().toISOString(),
+  };
+  if (event.error) {
+    attributes['error.message'] = event.error;
+  } else if (event.status_code) {
+    if (typeof event.status_code === 'number') {
+      attributes[SemanticAttributes.HTTP_STATUS_CODE] = event.status_code;
+    }
+  }
+
+  const logger = logs.getLogger(SERVICE_NAME);
+  const logRecord: LogRecord = {
+    body: `API response from ${event.model}. Status: ${event.status_code || 'N/A'}. Duration: ${event.duration_ms}ms.`,
+    attributes,
+  };
+  logger.emit(logRecord);
+  recordApiResponseMetrics(
+    event.model,
+    event.duration_ms,
+    event.status_code,
+    event.error,
+  );
+}