Function extractResponseText

packages/opencode/src/cli/cmd/github.shared.ts:10–18

(parts: SessionV1.Part[])

 * Throws only for truly empty responses.
 */
export function extractResponseText(parts: SessionV1.Part[]): string | null {
  const textPart = parts.findLast((p) => p.type === "text")
  if (textPart) return textPart.text

  // Non-text parts (tools, reasoning, step-start/step-finish, etc.) - signal summary needed
  if (parts.length > 0) return null

  throw new Error("Failed to parse response: no parts returned")
}

/**
 * Formats a PROMPT_TOO_LARGE error message with details about files in the prompt.