Use when the user asks to look at, review, or analyze THEIR portfolio / holdings / positions — e.g. "analyze my portfolio", "how is my portfolio doing", "what's in my portfolio", "review my holdings", "how am I invested", "what should I improve". Fetches a deep snapshot of ONE of the signed-in user's portfolios: the summary (value, day change, total return), every holding (with position weight %, sector and return) and Bullrun's computed insights (benchmark comparison, concentration, diversification, dividend income). Pass a portfolioId from list_portfolios (call that first if the user hasn't named a portfolio). The response ALWAYS returns the complete holdings list with each position flagged matched/unmatched, plus a `coverage` summary: holdings that Bullrun can't link to its universe (ETFs, funds, untracked tickers) carry no weight, sector, insight or ML score, so weights/insights/ML below describe ONLY the matched subset. Read the coverage banner (the first text block) and never present matched-only figures as the whole portfolio. For risk/diversification math, correlations, factor exposure, or whether to add a specific stock, use get_portfolio_analytics instead. Requires OAuth (read:portfolios) and returns the caller's own data only. privacyMode defaults to "full" (absolute $ included); "weights_only" returns only relative figures. Read-only.