Transcript ReturnLine

ReturnLine

The line that closes a child agent's work: "Map UsageState transitions returned", with a status pill and an Open action for the child's chat. This sheet also covers InterruptedNotice, the line that closes a run stopped by a host restart, with Resume.

import 'package:agent_kit/agent_kit.dart';

Demo

Done and failed: the two ReturnLine specimens from the gallery's "Return line and interrupted notice" group. The done line carries the "Result ready" pill; the failed line carries "Failed". Both show Open because the specimens pass onOpen.

Interrupted: InterruptedNotice(onResume: ...) with the default text. The Resume button is drawn because the callback is set.

Parameters

ReturnLine

Parameter	Type	Notes
result	ChildResult	Required, positional. Uses task (bold), state (the verb and the pill) and childId.
onOpen	ValueChanged<String>?	"Open". Gets result.childId. Not drawn when null.

Verb and pill for each WorkState:

State	Verb	Pill
running	is running	running
done	returned	"Result ready" (done)
failed	failed	failed
cancelled	was cancelled	"Cancelled" (idle)
waitingForAnswer	is waiting for an answer	idle
idle	is idle	idle
timedOut	timed out	"Timed out" (failed)

InterruptedNotice

Parameter	Type	Notes
text	String	Default "Interrupted by a restart". Drawn beside the interrupted mark.
onResume	VoidCallback?	"Resume", with a refresh glyph. Not drawn when null.

In the chat pane, onResume is set only when the backend has KitCapability.resume (packages/agent_kit/lib/src/compositions/agent_chat_pane.dart, lines 571 to 574). Without it the notice has no button.

Theme roles

• colors.borderSubtle: the top and bottom rules of both lines.
• colors.iconSecondary: the eye glyph on ReturnLine.
• muted: the verb. ink: the bold task name and the Open and Resume buttons.
• Pills and the interrupted mark come from StatusMark, so their colours are that widget's, not set here.

The text is 13/16 at weight 500, set from a fixed TypeSpec in the file, not from typeScale.

Size classes

ReturnLine reads sizeClassOf(context).isCompact. When compact, the pill is hidden and Open stays. The task and verb text can wrap to two lines, then ellipsis. InterruptedNotice does not read the size class.

Accessibility

• ReturnLine: Semantics(container: true, label: '<task> <verb>'). The Open button keeps its own button semantics.
• InterruptedNotice: Semantics(container: true, label: <text>). The Resume button keeps its own button semantics.
• No keyboard handling in either file. Taps on the buttons are KitTextButton's.

Gallery and tests

• Gallery scene: Components. Specimens "Return line and interrupted notice" in TranscriptSpecimens (apps/gallery/lib/components/transcript.dart, lines 114 to 119). The results are _childResult (done, task "Map UsageState transitions") and _childFailed (failed, task "Survey quota handling in Codex").
• Golden: apps/gallery/test/component_shots_test.dart writes return_line from ReturnLine indices 1 and 2, and interrupted_notice from InterruptedNotice index 1, light and dark. Index 0 of each is inside the transcript list.
• Other tests, in packages/agent_kit/test/transcript/transcript_test.dart:
  • "a child result opens the child" (line 460);
  • "the interrupted notice resumes" (line 472).
• Transcript goldens in packages/agent_kit/test/goldens/transcript_turn_*.png and transcript_states_*.png.

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Generated from docs/components/transcript/ReturnLine.md. Edit the file there; changes made on the wiki are overwritten.