geminixiang · Oct 26, 2026 · Oct 26, 2026 · Oct 26, 2026
diff --git a/src/events/index.ts b/src/events/index.ts
@@ -164,6 +164,21 @@ function isValidIsoTimestampWithOffset(value: string): boolean {
   );
 }
 
+const EVENT_RUN_ID_PREFIX = "event:";
+
+export function eventRunId(filename: string): string {
+  return `${EVENT_RUN_ID_PREFIX}${filename.replace(/\.json$/i, "")}`;
+}
+
+export function isEventRunId(id: string): boolean {
+  return id.startsWith(EVENT_RUN_ID_PREFIX);
+}
+
+export function eventRunName(id: string): string | undefined {
+  if (!isEventRunId(id)) return undefined;
+  return id.slice(EVENT_RUN_ID_PREFIX.length).split(":")[0] || undefined;
+}
+
 export function parseEventPayload(content: string, filename: string): EventFilePayload {
   const data: EventFileData = parseJsonSchemaValue(content, EventFileSchema, (detail, kind) =>
     kind === "shape"

diff --git a/src/events/scheduler.ts b/src/events/scheduler.ts
@@ -9,6 +9,7 @@ import { reportUserFacingError } from "../observability/index.js";
 import { inferConversationKind } from "../sessions/session-key.js";
 import type { OfficeAddress } from "../types.js";
 import {
+  eventRunId,
   officeEventsDir,
   parseEventPayload,
   type EventRecord,
@@ -182,7 +183,7 @@ export class EventScheduler implements EventScheduleSink {
         conversationKind: event.conversationKind,
         user: event.userId ?? "EVENT",
         text: buildEventPrompt(event),
-        ts: `event:${filename.replace(/\.json$/i, "")}`,
+        ts: eventRunId(filename),
       }),
     );
     if (!enqueued) {

diff --git a/src/harness/mcp.ts b/src/harness/mcp.ts
@@ -17,7 +17,7 @@ import {
 import { defineTool, type ToolRegistration } from "@earendil-works/pi-durable";
 import { guardMcpToolResult } from "./mcp-result.js";
 import { TOOL_SEARCH_TOOL_NAME as TOOL_SEARCH_TOOL } from "@earendil-works/pi-durable/tool-search";
-import { LABEL_PARAMETER } from "./tools/host-fn-tool.js";
+import { withLabelParameter, withoutLabel } from "./tools/host-fn-tool.js";
 import { Type, type TSchema } from "typebox";
 
 import { readStandardEnv } from "../env-manifest.js";
@@ -239,7 +239,12 @@ async function connectServer(
         callers: exposure === "codemode" ? ["tools"] : undefined,
         deferred: exposure === "deferred" ? true : undefined,
         description: mcpTool.description ?? `${mcpTool.name} (MCP server "${name}")`,
-        parameters: ownsLabel ? mcpTool.inputSchema : withLabelParameter(mcpTool.inputSchema),
+        parameters: ownsLabel
+          ? mcpTool.inputSchema
+          : withLabelParameter<McpInputSchema>(
+              { ...mcpTool.inputSchema, type: "object" },
+              "required",
+            ),
         structuredOutputSchema: mcpResultSchema(mcpTool.outputSchema),
         execute: async (params, api, context) => {
           const result = await client.callTool(
@@ -269,22 +274,6 @@ function schemaProperties(schema: McpInputSchema): Record<string, unknown> {
   return isRecord(schema.properties) ? schema.properties : {};
 }
 
-function withLabelParameter(schema: McpInputSchema): McpInputSchema {
-  const required = Array.isArray(schema.required) ? schema.required : [];
-  return {
-    ...schema,
-    type: "object",
-    properties: { label: LABEL_PARAMETER, ...schemaProperties(schema) },
-    required: ["label", ...required],
-  };
-}
-
-function withoutLabel(params: unknown): Record<string, unknown> {
-  if (!isRecord(params)) return {};
-  const { label: _label, ...rest } = params;
-  return rest;
-}
-
 function mcpResultSchema(structuredContent: Record<string, unknown> | undefined): TSchema {
   return Type.Object({
     content: Type.Array(Type.Object({})),

diff --git a/src/harness/presenter.ts b/src/harness/presenter.ts
@@ -28,7 +28,7 @@ import {
 import { appendTriggerAttribution } from "./prompt.js";
 import { START_TASK_TOOL, TASK_STATUS_TOOL } from "./tools/task.js";
 import { JEV_BROWSER_TOOL } from "./tools/jev-browser.js";
-import { toRunEvent, toolResultText } from "./run-events.js";
+import { toRunEvent, toolLabel, toolResultText } from "./run-events.js";
 import { REACT_TOOL } from "./tools/react.js";
 
 import * as log from "../log.js";
@@ -72,7 +72,7 @@ function endOutstandingOperationSpans(runState: RunnerSessionState): void {
   operationSpans.delete(runState);
 }
 
-function createRunStateDefaults(): RunnerSessionState {
+export function createRunState(): RunnerSessionState {
   return {
     responder: null,
     logCtx: null,
@@ -105,16 +105,12 @@ function createRunStateDefaults(): RunnerSessionState {
   };
 }
 
-export function createRunState(): RunnerSessionState {
-  return createRunStateDefaults();
-}
-
 export function activateRunPresentation(
   runState: RunnerSessionState,
   context: RunPresentationContext,
 ): RunPresentation {
   endOutstandingOperationSpans(runState);
-  Object.assign(runState, createRunStateDefaults(), {
+  Object.assign(runState, createRunState(), {
     responder: context.responder,
     logCtx: {
       conversationId: context.sessionConversation,
@@ -161,10 +157,6 @@ export function getFinalAssistantText(session: MikanAgentSession): string {
   return contentText(lastAssistant?.content ?? []);
 }
 
-export function isEventTriggerAttribution(triggerAttribution: string | undefined): boolean {
-  return triggerAttribution?.startsWith("[event:") === true;
-}
-
 function formatToolProgress(runState: RunnerSessionState): string {
   const lines = Array.from(runState.toolProgress.values()).map((item) => {
     const marker = item.status === "running" ? "•" : item.status === "error" ? "✗" : "✓";
@@ -432,11 +424,6 @@ type LifecycleEvent = Extract<
   { type: "compaction_start" | "compaction_end" | "auto_retry_start" | "budget_exceeded" }
 >;
 
-function toolLabel(args: unknown, toolName: string): string {
-  const label = isRecord(args) && typeof args.label === "string" ? args.label.trim() : "";
-  return label || toolName;
-}
-
 function runningTools(runState: RunnerSessionState): ToolTiming[] {
   const now = Date.now();
   return [...runState.pendingTools.values()]
@@ -795,17 +782,21 @@ function presentThinking(thinking: string, context: FrontProjectionContext): voi
   );
 }
 
-function presentFinalText(text: string, context: FrontProjectionContext): void {
-  log.logResponse(context.logCtx, text);
-}
-
 function presentAssistantMessage(
   event: RunEventOf<"assistant_message">,
   context: FrontProjectionContext,
 ): void {
   for (const thinking of event.thinking) presentThinking(thinking, context);
   if (!event.text.trim() || event.callsTools || context.runState.finalResponseHandledByTool) return;
-  presentFinalText(event.text, context);
+  log.logResponse(context.logCtx, event.text);
+}
+
+function presentNotice(notice: string, errorContext: string, context: FrontProjectionContext) {
+  context.runState.notice = notice;
+  context.queue.enqueue(
+    () => replaceResponseWithToolProgress(context.responder, context.runState),
+    errorContext,
+  );
 }
 
 function presentRunEvent(event: RunEvent, context: FrontProjectionContext): void {
@@ -823,20 +814,11 @@ function presentRunEvent(event: RunEvent, context: FrontProjectionContext): void
       presentAssistantMessage(event, context);
       return;
     case "compaction_started":
-      context.runState.notice = "_Compacting context..._";
-      context.queue.enqueue(
-        () => replaceResponseWithToolProgress(context.responder, context.runState),
-        "compaction start",
-      );
+      presentNotice("_Compacting context..._", "compaction start", context);
       return;
-    case "retry_started": {
-      context.runState.notice = `_Retrying (${event.attempt}/${event.maxAttempts})..._`;
-      context.queue.enqueue(
-        () => replaceResponseWithToolProgress(context.responder, context.runState),
-        "retry",
-      );
+    case "retry_started":
+      presentNotice(`_Retrying (${event.attempt}/${event.maxAttempts})..._`, "retry", context);
       return;
-    }
     case "budget_exceeded": {
       const text = formatBudgetStop({
         reason: event.reason,

diff --git a/src/harness/prompt.ts b/src/harness/prompt.ts
@@ -11,6 +11,7 @@ import type { BuildSystemPromptOptions, ScratchListing } from "./types.js";
 import { pinDirectoryNoFollow, readTextFileNoFollowIfExists } from "../file-guards.js";
 import type { PinnedDirectory } from "../file-guards.js";
 import * as log from "../log.js";
+import { eventRunName } from "../events/index.js";
 
 const IMAGE_MIME_TYPES: Record<string, string> = {
   jpg: "image/jpeg",
@@ -178,8 +179,8 @@ function buildEnvDescription(sandboxType: SandboxConfig["type"], workspaceRoot:
 export function resolveTriggerAttribution(
   message: Pick<ConversationMessage, "id" | "text" | "userName">,
 ): string | undefined {
-  const eventIdMatch = message.id.match(/^event:([^:]+)/);
-  if (eventIdMatch) return `[event: ${eventIdMatch[1]}]`;
+  const eventName = eventRunName(message.id);
+  if (eventName !== undefined) return `[event: ${eventName}]`;
   if (message.userName) return `@${message.userName}`;
   return undefined;
 }

diff --git a/src/harness/run-events.ts b/src/harness/run-events.ts
@@ -2,14 +2,16 @@ import { JEV_TOOL } from "./tools/jev.js";
 import { JEV_BROWSER_TOOL } from "./tools/jev-browser.js";
 import type { OfficeAddress } from "../types.js";
 import * as log from "../log.js";
-import { errorMessage } from "../unknown-values.js";
+import { errorMessage, isRecord } from "../unknown-values.js";
 import type { HarnessEvent, RunEvent, RunEventListener } from "./types.js";
 
-const TOOL_CALL_PART_TYPES = new Set(["tool_use", "toolCall", "tool-call"]);
+export function toolLabel(args: unknown, toolName: string): string {
+  const label = isRecord(args) && typeof args.label === "string" ? args.label.trim() : "";
+  return label || toolName;
+}
 
 function toolDisplayLabel(toolName: string, args: unknown): string {
-  const label = (args as { label?: unknown } | undefined)?.label;
-  const text = typeof label === "string" ? label.trim() || toolName : toolName;
+  const text = toolLabel(args, toolName);
   if ((toolName === JEV_TOOL || toolName === JEV_BROWSER_TOOL) && text !== toolName) {
     return `${toolName} · ${text}`;
   }
@@ -44,7 +46,7 @@ function assistantMessageParts(message: Extract<AssistantMessageEvent, { role: "
   for (const part of message.content) {
     if (part.type === "thinking") thinking.push(part.thinking);
     else if (part.type === "text") text.push(part.text);
-    if (TOOL_CALL_PART_TYPES.has((part as { type?: string }).type ?? "")) callsTools = true;
+    else if (part.type === "toolCall") callsTools = true;
   }
   return { thinking, text: text.join("\n"), callsTools };
 }