fix

Author: icecrasher321

apps/sim/lib/logs/execution/trace-spans/span-factory.ts

@@ -1,4 +1,5 @@
 import { createLogger } from '@sim/logger'
+import { isRecordLike } from '@sim/utils/object'
 import type { ProviderTiming, TraceSpan } from '@/lib/logs/types'
 import {
   isConditionBlockType,
@@ -17,6 +18,12 @@ const logger = createLogger('SpanFactory')
 /** A BlockLog that has already passed the id/type validity check. */
 type ValidBlockLog = BlockLog & { blockType: string }
 
+/** Converts arbitrary tool results to the object shape expected by trace spans. */
+function normalizeTraceOutput(value: unknown): Record<string, unknown> | undefined {
+  if (value === undefined) return undefined
+  return isRecordLike(value) ? value : { value }
+}
+
 /**
  * Creates a TraceSpan from a BlockLog. Returns null for invalid logs.
  *
@@ -190,6 +197,7 @@ function buildChildrenFromTimeSegments(
       const currentIndex = toolCallIndices.get(normalizedName) ?? 0
       const match = callsForName[currentIndex]
       toolCallIndices.set(normalizedName, currentIndex + 1)
+      const output = normalizeTraceOutput(match?.result ?? match?.output)
 
       const toolChild: TraceSpan = {
         id: `${span.id}-segment-${index}`,
@@ -200,9 +208,7 @@ function buildChildrenFromTimeSegments(
         endTime: segmentEndTime,
         status: match?.error || segment.errorMessage ? 'error' : 'success',
         input: match?.arguments ?? match?.input,
-        output: match?.error
-          ? { error: match.error, ...(match.result ?? match.output ?? {}) }
-          : (match?.result ?? match?.output),
+        output: match?.error ? { error: match.error, ...output } : output,
       }
       if (segment.toolCallId) toolChild.toolCallId = segment.toolCallId
       if (segment.errorType) toolChild.errorType = segment.errorType
@@ -269,6 +275,7 @@ function buildChildrenFromToolCalls(span: TraceSpan, log: ValidBlockLog): TraceS
   return toolCalls.map((tc, index) => {
     const startTime = tc.startTime ?? log.startedAt
     const endTime = tc.endTime ?? log.endedAt
+    const output = normalizeTraceOutput(tc.result ?? tc.output)
     return {
       id: `${span.id}-tool-${index}`,
       name: stripCustomToolPrefix(tc.name ?? 'unnamed-tool'),
@@ -278,9 +285,7 @@ function buildChildrenFromToolCalls(span: TraceSpan, log: ValidBlockLog): TraceS
       endTime,
       status: tc.error ? 'error' : 'success',
       input: tc.arguments ?? tc.input,
-      output: tc.error
-        ? { error: tc.error, ...(tc.result ?? tc.output ?? {}) }
-        : (tc.result ?? tc.output),
+      output: tc.error ? { error: tc.error, ...output } : output,
     }
   })
 }

apps/sim/lib/logs/execution/trace-spans/trace-spans.test.ts

@@ -196,6 +196,34 @@ describe('buildTraceSpans', () => {
     expect(secondToolCall.output).toEqual({ status: 200, data: 'response' })
   })
 
+  it.concurrent('normalizes scalar tool results only at the trace display boundary', () => {
+    const mockExecutionResult: ExecutionResult = {
+      success: true,
+      output: { content: 'Final output' },
+      logs: [
+        {
+          blockId: 'agent-scalar',
+          blockName: 'Scalar Agent',
+          blockType: 'agent',
+          startedAt: '2024-01-01T10:00:00.000Z',
+          endedAt: '2024-01-01T10:00:01.000Z',
+          durationMs: 1000,
+          success: true,
+          output: {
+            toolCalls: {
+              list: [{ name: 'boolean_tool', result: false }],
+              count: 1,
+            },
+          },
+        },
+      ],
+    }
+
+    const { traceSpans } = buildTraceSpans(mockExecutionResult)
+
+    expect(traceSpans[0].children?.[0].output).toEqual({ value: false })
+  })
+
   it.concurrent(
     'extracts tool calls from agent block output with direct toolCalls array format',
     () => {