earendil-works/pi · error · Error

Agent run completed without an assistant message.

Error message

Agent run completed without an assistant message.

What it means

Error "Agent run completed without an assistant message." thrown in earendil-works/pi.

Source

Thrown at packages/evals/src/pi-harness.ts:98

				toolCallId: message.toolCallId,
				name: message.toolName,
				content: message.content.every((part) => part.type === "text") ? text : toJsonValue(message.content),
				...(message.isError ? { error: { message: text || "Tool failed" } } : {}),
			});
		}
	}
	return events;
}

async function promptAgent(session: AgentSession, input: string, signal: AbortSignal | undefined): Promise<string> {
	signal?.throwIfAborted();
	const previousMessageCount = session.messages.length;
	await session.prompt(input);
	const assistant = session.messages
		.slice(previousMessageCount)
		.reverse()
		.find((message) => message.role === "assistant");
	if (!assistant) throw new Error("Agent run completed without an assistant message.");
	if (assistant.stopReason !== "stop") {
		throw new Error(
			assistant.errorMessage ?? `Agent run ended with unexpected stop reason: ${assistant.stopReason}.`,
		);
	}
	const output = session.getLastAssistantText();
	if (!output) throw new Error("Agent run produced no assistant text.");
	return output;
}

async function runPiCodingAgent<TOutput extends JsonValue>(
	input: PiCodingAgentInput,
	signal: AbortSignal | undefined,
	setArtifact: HarnessContext["setArtifact"],
	options: PiCodingAgentHarnessOptions | PiCodingAgentHarnessWithOutput<TOutput>,
): Promise<SimpleHarnessResult<string | TOutput>> {
	const startedAt = performance.now();
	signal?.throwIfAborted();

View on GitHub (pinned to 4af9d21d3b)

When it happens

Trigger: Thrown at packages/evals/src/pi-harness.ts:98 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/173d81b50e007ccf. Report an issue: GitHub.