earendil-works/pi · error · Error

Select a harness model explicitly or set both PI_PROVIDER an

Error message

Select a harness model explicitly or set both PI_PROVIDER and PI_MODEL as defaults.

What it means

Error "Select a harness model explicitly or set both PI_PROVIDER and PI_MODEL as defaults." thrown in earendil-works/pi.

Source

Thrown at packages/evals/src/pi-harness.ts:53

type PiCodingAgentHarnessOptions = {
	name?: string;
	model?: PiCodingAgentModelSelection;
	noTools?: CreateAgentSessionOptions["noTools"];
	transformSystemPrompt?: (defaultPrompt: string) => string;
};

type PiCodingAgentHarnessWithOutput<TOutput extends JsonValue> = PiCodingAgentHarnessOptions & {
	output: (args: { response: string; session: AgentSession }) => TOutput | Promise<TOutput>;
};

export function resolveModelSelection(
	explicitModel: PiCodingAgentModelSelection | undefined,
	environment: { PI_PROVIDER?: string; PI_MODEL?: string } = process.env,
): PiCodingAgentModelSelection {
	const provider = (explicitModel?.provider ?? environment.PI_PROVIDER)?.trim();
	const id = (explicitModel?.id ?? environment.PI_MODEL)?.trim();
	if (!provider || !id) {
		throw new Error("Select a harness model explicitly or set both PI_PROVIDER and PI_MODEL as defaults.");
	}
	return { provider, id };
}

function toTranscriptEvents(messages: AgentSession["messages"]): TranscriptEvent[] {
	const events: TranscriptEvent[] = [];
	for (const message of messages) {
		if (message.role === "user") {
			events.push({ type: "message", role: "user", content: contentText(message.content) });
		} else if (message.role === "assistant") {
			const text = contentText(message.content);
			if (text) events.push({ type: "message", role: "assistant", content: text });
			for (const part of message.content) {
				if (part.type === "toolCall") {
					events.push({
						type: "tool_call",
						id: part.id,
						name: part.name,

View on GitHub (pinned to 4af9d21d3b)

When it happens

Trigger: Thrown at packages/evals/src/pi-harness.ts:53 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of earendil-works/pi@4af9d21d3b (2026-08-24). Data as JSON: /api/errors/68fb6776a8faeb6e. Report an issue: GitHub.