- Tool calls
+ Tool calls{longOutput ? ` (${turnLineCount(pretty)} lines)` : ""}
{pretty}
diff --git a/src/web/runDetailUtils.test.ts b/src/web/runDetailUtils.test.ts
new file mode 100644
index 0000000..353269e
--- /dev/null
+++ b/src/web/runDetailUtils.test.ts
@@ -0,0 +1,122 @@
+import { describe, expect, it } from "vitest";
+import type { ApiEvent } from "./api.js";
+import {
+ ASSISTANT_LINE_THRESHOLD,
+ TOOL_LINE_THRESHOLD,
+ collapsedSummary,
+ findErrorEvents,
+ shouldCollapseTurn,
+ stepCursor,
+ turnLineCount,
+ turnLineThreshold,
+} from "./runDetailUtils.js";
+
+function ev(id: number, eventType: string): ApiEvent {
+ return {
+ id,
+ runId: "r",
+ turnId: null,
+ eventType,
+ issueId: null,
+ payload: null,
+ ts: "2026-05-03T00:00:00.000Z",
+ };
+}
+
+describe("turnLineCount", () => {
+ it("returns 0 for empty content", () => {
+ expect(turnLineCount("")).toBe(0);
+ });
+ it("counts a single line as 1", () => {
+ expect(turnLineCount("hello")).toBe(1);
+ });
+ it("counts trailing newlines", () => {
+ expect(turnLineCount("a\nb\n")).toBe(3);
+ });
+});
+
+describe("turnLineThreshold", () => {
+ it("uses the tool threshold for tool turns", () => {
+ expect(turnLineThreshold("tool")).toBe(TOOL_LINE_THRESHOLD);
+ });
+ it("uses the assistant threshold for assistant turns", () => {
+ expect(turnLineThreshold("assistant")).toBe(ASSISTANT_LINE_THRESHOLD);
+ });
+ it("falls back to the assistant threshold for unknown roles", () => {
+ expect(turnLineThreshold("user")).toBe(ASSISTANT_LINE_THRESHOLD);
+ });
+});
+
+describe("shouldCollapseTurn", () => {
+ it("does not collapse short content", () => {
+ expect(shouldCollapseTurn("a\nb\nc", ASSISTANT_LINE_THRESHOLD)).toBe(false);
+ });
+ it("collapses content above the threshold", () => {
+ const long = Array.from({ length: ASSISTANT_LINE_THRESHOLD + 1 }, (_, i) => `line ${i}`).join(
+ "\n",
+ );
+ expect(shouldCollapseTurn(long, ASSISTANT_LINE_THRESHOLD)).toBe(true);
+ });
+ it("does not collapse exactly at the threshold", () => {
+ const exact = Array.from({ length: ASSISTANT_LINE_THRESHOLD }, (_, i) => `line ${i}`).join(
+ "\n",
+ );
+ expect(shouldCollapseTurn(exact, ASSISTANT_LINE_THRESHOLD)).toBe(false);
+ });
+ it("collapses any multi-line tool content above the tool threshold", () => {
+ expect(shouldCollapseTurn("a\nb", TOOL_LINE_THRESHOLD)).toBe(true);
+ });
+});
+
+describe("collapsedSummary", () => {
+ it("returns the full content when under the threshold", () => {
+ const out = collapsedSummary("a\nb", ASSISTANT_LINE_THRESHOLD);
+ expect(out).toEqual({ head: "a\nb", remaining: 0 });
+ });
+ it("returns the first N lines and the remaining count", () => {
+ const long = Array.from({ length: 20 }, (_, i) => `line ${i}`).join("\n");
+ const out = collapsedSummary(long, 5);
+ expect(out.head.split("\n")).toHaveLength(5);
+ expect(out.head).toBe("line 0\nline 1\nline 2\nline 3\nline 4");
+ expect(out.remaining).toBe(15);
+ });
+ it("collapses tool output to the first line when threshold is 1", () => {
+ const out = collapsedSummary("first\nsecond\nthird", TOOL_LINE_THRESHOLD);
+ expect(out).toEqual({ head: "first", remaining: 2 });
+ });
+});
+
+describe("findErrorEvents", () => {
+ it("matches eventType containing 'error' case-insensitively", () => {
+ const events = [
+ ev(1, "runStarted"),
+ ev(2, "error"),
+ ev(3, "rate_limit_error"),
+ ev(4, "TURN_ERROR"),
+ ev(5, "runFinished"),
+ ];
+ expect(findErrorEvents(events).map((e) => e.id)).toEqual([2, 3, 4]);
+ });
+ it("returns empty when none match", () => {
+ expect(findErrorEvents([ev(1, "tick")])).toEqual([]);
+ });
+});
+
+describe("stepCursor", () => {
+ it("returns -1 when there are no items", () => {
+ expect(stepCursor(0, -1, 1)).toBe(-1);
+ expect(stepCursor(0, 5, -1)).toBe(-1);
+ });
+ it("seeds forward to 0 from the unset cursor", () => {
+ expect(stepCursor(3, -1, 1)).toBe(0);
+ });
+ it("seeds backward to the last index from the unset cursor", () => {
+ expect(stepCursor(3, -1, -1)).toBe(2);
+ });
+ it("wraps forward at the end", () => {
+ expect(stepCursor(3, 2, 1)).toBe(0);
+ });
+ it("wraps backward at the start", () => {
+ expect(stepCursor(3, 0, -1)).toBe(2);
+ });
+});
diff --git a/src/web/runDetailUtils.ts b/src/web/runDetailUtils.ts
new file mode 100644
index 0000000..fe63f56
--- /dev/null
+++ b/src/web/runDetailUtils.ts
@@ -0,0 +1,42 @@
+import type { ApiEvent } from "./api.js";
+
+export const ASSISTANT_LINE_THRESHOLD = 12;
+export const TOOL_LINE_THRESHOLD = 1;
+
+export function turnLineThreshold(role: string): number {
+ return role === "tool" ? TOOL_LINE_THRESHOLD : ASSISTANT_LINE_THRESHOLD;
+}
+
+export function turnLineCount(content: string): number {
+ if (content.length === 0) return 0;
+ return content.split("\n").length;
+}
+
+export function shouldCollapseTurn(content: string, threshold: number): boolean {
+ return turnLineCount(content) > threshold;
+}
+
+export function collapsedSummary(
+ content: string,
+ threshold: number,
+): { head: string; remaining: number } {
+ const lines = content.split("\n");
+ if (lines.length <= threshold) return { head: content, remaining: 0 };
+ return { head: lines.slice(0, threshold).join("\n"), remaining: lines.length - threshold };
+}
+
+const ERROR_EVENT_RE = /error/i;
+
+export function findErrorEvents(events: ReadonlyArray): ApiEvent[] {
+ return events.filter((e) => ERROR_EVENT_RE.test(e.eventType));
+}
+
+export function stepCursor(total: number, current: number, dir: 1 | -1): number {
+ if (total <= 0) return -1;
+ if (current < 0) return dir === 1 ? 0 : total - 1;
+ return (current + dir + total) % total;
+}
+
+export function eventDomId(eventId: number): string {
+ return `event-${eventId}`;
+}