Forward dropped SDK events to ACP clients

src/acp-agent.ts

@@ -486,7 +486,6 @@ export class ClaudeAcpAgent implements Agent {
       cachedReadTokens: 0,
       cachedWriteTokens: 0,
     };
-
     let lastAssistantTotalUsage: number | null = null;
     let lastAssistantModel: string | null = null;
     let lastContextWindowSize: number = 200000;
@@ -602,9 +601,26 @@ export class ClaudeAcpAgent implements Agent {
               case "task_notification":
               case "task_progress":
               case "elicitation_complete":
-              case "api_retry":
-                // Todo: process via status api: https://docs.claude.com/en/docs/claude-code/hooks#hook-output
                 break;
+              case "api_retry": {
+                // Forward API retry events via extNotification so clients can observe
+                // transient failures including HTTP status code and typed error category.
+                const retryMsg = message as any;
+                this.logger.error(
+                  `API retry: attempt=${retryMsg.attempt}/${retryMsg.max_retries}, ` +
+                  `httpStatus=${retryMsg.error_status}, error=${retryMsg.error}, ` +
+                  `delay=${retryMsg.retry_delay_ms}ms`,
+                );
+                await this.client.extNotification("_claude/api-retry", {
+                  sessionId: params.sessionId,
+                  httpStatus: retryMsg.error_status ?? null,
+                  errorType: retryMsg.error ?? "unknown",
+                  attempt: retryMsg.attempt ?? 0,
+                  maxRetries: retryMsg.max_retries ?? 0,
+                  retryDelayMs: retryMsg.retry_delay_ms ?? 0,
+                });
+                break;
+              }
               default:
                 unreachable(message, this.logger);
                 break;
@@ -835,11 +851,57 @@ export class ClaudeAcpAgent implements Agent {
             }
             break;
           }
-          case "tool_progress":
-          case "tool_use_summary":
+          case "tool_progress": {
+            // Forward tool execution progress via extNotification so clients can
+            // show elapsed time for long-running tools without polluting tool output.
+            const toolUseId = "tool_use_id" in message ? (message as any).tool_use_id : undefined;
+            if (toolUseId) {
+              await this.client.extNotification("_claude/tool-progress", {
+                sessionId: params.sessionId,
+                toolUseId,
+                toolName: (message as any).tool_name ?? null,
+                elapsedTimeSeconds: (message as any).elapsed_time_seconds ?? 0,
+              });
+            }
+            break;
+          }
+          case "tool_use_summary": {
+            // Forward collapsed tool-use summaries via extNotification so clients
+            // can display a high-level overview of tool activity.
+            const summary = "summary" in message ? (message as any).summary : undefined;
+            if (summary) {
+              await this.client.extNotification("_claude/tool-use-summary", {
+                sessionId: params.sessionId,
+                summary,
+                precedingToolUseIds:
+                  "preceding_tool_use_ids" in message
+                    ? (message as any).preceding_tool_use_ids ?? []
+                    : [],
+              });
+            }
+            break;
+          }
+          case "rate_limit_event": {
+            // Forward rate limit info via extNotification so clients can detect
+            // approaching limits and rejections without parsing error message strings.
+            const info = "rate_limit_info" in message ? (message as any).rate_limit_info : undefined;
+            if (info) {
+              await this.client.extNotification("_claude/rate-limit", {
+                sessionId: params.sessionId,
+                status: info.status ?? "unknown",
+                resetsAt: info.resetsAt ?? null,
+                rateLimitType: info.rateLimitType ?? null,
+                utilization: info.utilization ?? null,
+                overageStatus: info.overageStatus ?? null,
+                overageDisabledReason: info.overageDisabledReason ?? null,
+                isUsingOverage: info.isUsingOverage ?? false,
+                surpassedThreshold: info.surpassedThreshold ?? null,
+              });
+            }
+            break;
+          }
           case "auth_status":
           case "prompt_suggestion":
-          case "rate_limit_event":
             break;
           default:
             unreachable(message);

src/tests/acp-agent.test.ts

@@ -1337,6 +1337,7 @@ describe("stop reason propagation", () => {
         availableModels: [],
       },
       settingsManager: { dispose: vi.fn() } as any,
+
       accumulatedUsage: {
         inputTokens: 0,
         outputTokens: 0,
@@ -1476,6 +1477,7 @@ describe("stop reason propagation", () => {
         availableModels: [],
       },
       settingsManager: { dispose: vi.fn() } as any,
+
       accumulatedUsage: {
         inputTokens: 0,
         outputTokens: 0,
@@ -1549,6 +1551,7 @@ describe("session/close", () => {
         availableModels: [],
       },
       settingsManager: { dispose: vi.fn() } as any,
+
       accumulatedUsage: {
         inputTokens: 0,
         outputTokens: 0,
@@ -1719,6 +1722,7 @@ describe("usage_update computation", () => {
         availableModels: [],
       },
       settingsManager: {} as any,
+
       accumulatedUsage: {
         inputTokens: 0,
         outputTokens: 0,