/**
* Structured Output Tool
*
* Demonstrates `terminate: true` so the agent can end on a tool call
* without paying for an extra follow-up LLM turn.
*/
import { defineTool, type ExtensionAPI } from "@earendil-works/pi-coding-agent";
import { Text } from "@earendil-works/pi-tui";
import { Type } from "typebox";
interface StructuredOutputDetails {
headline: string;
summary: string;
actionItems: string[];
}
const structuredOutputTool = defineTool({
name: "structured_output",
label: "Structured Output",
description:
"Return a final structured answer. Use this as your last action when the user asks for structured output or a machine-readable summary.",
promptSnippet: "Emit a final structured answer as a terminating tool result",
promptGuidelines: [
"Use structured_output as your final action when the user asks for structured output, JSON-like output, or a machine-readable summary.",
"After calling structured_output, do not emit another assistant response in the same turn.",
],
parameters: Type.Object({
headline: Type.String({ description: "Short title for the result" }),
summary: Type.String({ description: "One-paragraph summary" }),
actionItems: Type.Array(Type.String(), { description: "Concrete next steps or key bullets" }),
}),
async execute(_toolCallId, params) {
return {
content: [{ type: "text", text: `Saved structured output: ${params.headline}` }],
details: {
headline: params.headline,
summary: params.summary,
actionItems: params.actionItems,
} satisfies StructuredOutputDetails,
terminate: true,
};
},
renderResult(result, _options, theme) {
const details = result.details as StructuredOutputDetails | undefined;
if (!details) {
const text = result.content[0];
return new Text(text?.type === "text" ? text.text : "", 0, 0);
}
const lines = [
theme.fg("toolTitle", theme.bold(details.headline)),
theme.fg("text", details.summary),
"",
...details.actionItems.map((item, index) => theme.fg("muted", `${index + 1}. ${item}`)),
];
return new Text(lines.join("\n"), 0, 0);
},
});
export default function (pi: ExtensionAPI) {
pi.registerTool(structuredOutputTool);
}