feat(core): enable retryFetchErrors by default and add user notifications

packages/core/src/config/config.ts

@@ -1018,7 +1018,7 @@ export class Config implements McpContext, AgentLoopContext {
           params.gemmaModelRouter?.classifier?.model ?? 'gemma3-1b-gpu-custom',
       },
     };
-    this.retryFetchErrors = params.retryFetchErrors ?? false;
+    this.retryFetchErrors = params.retryFetchErrors ?? true;
     this.maxAttempts = Math.min(
       params.maxAttempts ?? DEFAULT_MAX_ATTEMPTS,
       DEFAULT_MAX_ATTEMPTS,

packages/core/src/core/baseLlmClient.ts

@@ -21,6 +21,8 @@ import { getErrorMessage } from '../utils/errors.js';
 import { logMalformedJsonResponse } from '../telemetry/loggers.js';
 import { MalformedJsonResponseEvent, LlmRole } from '../telemetry/types.js';
 import { retryWithBackoff } from '../utils/retry.js';
+import { coreEvents } from '../utils/events.js';
+import { getDisplayString } from '../config/models.js';
 import type { ModelConfigKey } from '../services/modelConfigService.js';
 import {
   applyModelSelection,
@@ -327,6 +329,17 @@ export class BaseLlmClient {
           : undefined,
         authType:
           this.authType ?? this.config.getContentGeneratorConfig()?.authType,
+        retryFetchErrors: this.config.getRetryFetchErrors(),
+        onRetry: (attempt, error, delayMs) => {
+          coreEvents.emitRetryAttempt({
+            attempt,
+            maxAttempts:
+              availabilityMaxAttempts ?? maxAttempts ?? DEFAULT_MAX_ATTEMPTS,
+            delayMs,
+            error: error instanceof Error ? error.message : String(error),
+            model: getDisplayString(currentModel),
+          });
+        },
       });
     } catch (error) {
       if (abortSignal?.aborted) {

packages/core/src/core/client.ts

@@ -29,6 +29,8 @@ import { getCoreSystemPrompt } from './prompts.js';
 import { checkNextSpeaker } from '../utils/nextSpeakerChecker.js';
 import { reportError } from '../utils/errorReporting.js';
 import { GeminiChat } from './geminiChat.js';
+import { coreEvents, CoreEvent } from '../utils/events.js';
+import { getDisplayString , resolveModel, isGemini2Model } from '../config/models.js';
 import {
   retryWithBackoff,
   type RetryAvailabilityContext,
@@ -69,9 +71,7 @@ import {
   applyModelSelection,
   createAvailabilityContextProvider,
 } from '../availability/policyHelpers.js';
-import { resolveModel, isGemini2Model } from '../config/models.js';
 import { partToString } from '../utils/partUtils.js';
-import { coreEvents, CoreEvent } from '../utils/events.js';
 
 const MAX_TURNS = 100;
 
@@ -1088,7 +1088,18 @@ export class GeminiClient {
         onValidationRequired: onValidationRequiredCallback,
         authType: this.config.getContentGeneratorConfig()?.authType,
         maxAttempts: availabilityMaxAttempts,
+        retryFetchErrors: this.config.getRetryFetchErrors(),
         getAvailabilityContext,
+        onRetry: (attempt, error, delayMs) => {
+          coreEvents.emitRetryAttempt({
+            attempt,
+            maxAttempts:
+              availabilityMaxAttempts ?? this.config.getMaxAttempts(),
+            delayMs,
+            error: error instanceof Error ? error.message : String(error),
+            model: getDisplayString(currentAttemptModel),
+          });
+        },
       });
 
       return result;

packages/core/src/tools/web-fetch.ts

@@ -29,6 +29,7 @@ import {
 import { LlmRole } from '../telemetry/llmRole.js';
 import { WEB_FETCH_TOOL_NAME } from './tool-names.js';
 import { debugLogger } from '../utils/debugLogger.js';
+import { coreEvents } from '../utils/events.js';
 import { retryWithBackoff } from '../utils/retry.js';
 import { WEB_FETCH_DEFINITION } from './definitions/coreTools.js';
 import { resolveToolDeclaration } from './definitions/resolver.js';
@@ -212,6 +213,15 @@ class WebFetchToolInvocation extends BaseToolInvocation<
         },
         {
           retryFetchErrors: this.config.getRetryFetchErrors(),
+          onRetry: (attempt, error, delayMs) => {
+            coreEvents.emitRetryAttempt({
+              attempt,
+              maxAttempts: this.config.getMaxAttempts(),
+              delayMs,
+              error: error instanceof Error ? error.message : String(error),
+              model: 'Web Fetch',
+            });
+          },
         },
       );
 
@@ -405,6 +415,15 @@ ${textContent}
         },
         {
           retryFetchErrors: this.config.getRetryFetchErrors(),
+          onRetry: (attempt, error, delayMs) => {
+            coreEvents.emitRetryAttempt({
+              attempt,
+              maxAttempts: this.config.getMaxAttempts(),
+              delayMs,
+              error: error instanceof Error ? error.message : String(error),
+              model: 'Web Fetch',
+            });
+          },
         },
       );