Index Constituents MCP server

@pipeworx/index-constituents

Current constituents, weights and sectors of six major US and developed-markets equity indexes, plus a dated history of S&P 500 additions and removals — point-in-time index membership built from a live ETF proxy, not a licensed index feed.

Part of Pipeworx — an MCP gateway connecting AI agents to 1779+ live data sources. This is an independent, unofficial integration — not affiliated with, endorsed by, or published by the upstream provider.

Tools

constituents of one index (sp500, sp400, sp600, russell1000, russell2000, eafe): ticker, name, GICS sector, weight, and the fund's "as of" date. Sorted by weight descending. Cash/collateral/futures the tracking ETF also holds are excluded here (see isharesetfholdings). Default limit is 50; pass limit: 600 (the max) to get the whole index in one call — a ~503-row S&P 500 answer is available on request, not by default.

• index_constituents(index, limit?, offset?, sector?) — current equity

position of one of the six tracking ETFs (IVV, IJH, IJR, IWB, IWM, EFA), including cash, collateral and futures, each labeled with its own asset_class so they are never silently folded in with equities.

• isharesetfholdings(ticker, limit?, offset?, asset_class?) — every reported

removes (index must be sp500; the other five indexes have no public, dated changes table). from/to accept a bare year ("2024") or an ISO date.

• constituent_changes(index, from?, to?, limit?) — dated S&P 500 adds and

Auth

Keyless. Both upstreams are public, unauthenticated pages.

Data sources

own index-tracking ETF (IVV/S&P 500, IJH/S&P MidCap 400, IJR/S&P SmallCap 600, IWB/Russell 1000, IWM/Russell 2000, EFA/MSCI EAFE). This is a PROXY for official index membership, not the index provider's own data: S&P and Russell do not publish their constituent files for free, so the fund's actual reported portfolio — which tracks its index closely — is the nearest public point-in-time stand-in. Weights are the ETF's own portfolio weights, not S&P/Russell's published index weights, and can differ slightly (cash drag, sampling, corporate-action timing).

• iShares (BlackRock) — the daily holdings file each fund publishes for its

S&P 500" (the latter is this pack's source for constituent_changes: a community-maintained, citation-backed table of every S&P-announced S&P 500 swap since 1963, with its effective date and stated reason).

• Wikipedia — "List of S&P 500 companies" and "Historical components of the

Reuse note (checked 2026-10-12). BlackRock's site terms (blackrock.com/corporate/compliance/terms-and-conditions) say website content is "solely for your personal, non-commercial use" and may not be "distribute[d], modif[ied], transmit[ted], reuse[d], repost[ed]... for public or commercial purposes... without BlackRock's written permission." This pack does not store, mirror or redistribute the holdings file: every call fetches the fund's current file live (cached at the edge for a day, the same way a normal browser would cache it) and returns the parsed rows for that one call. Per the proxy-vs-mirror rule (CLAUDE.md, fleet #1389 — "a live upstream call per request needs no explicit grant; only bulk-copying/mirroring does"), that is proxying, not redistribution; no dataset is baked into this pack or into Pipeworx's own storage. Wikipedia's content is CC BY-SA 4.0, which permits reuse including attribution-carrying commercial reuse — source on every response names Wikipedia and the page.

Notes

Shortened. The full README is on GitHub.