MCP server exposing 3 tools for index-constituents.
This URL is a JSON-RPC 2.0 endpoint over HTTP. Issue POST requests with a JSON-RPC body. Browsers and search crawlers land here on GET.
POST https://gateway.pipeworx.io/index-constituents/mcp
Content-Type: application/json
{"jsonrpc":"2.0","id":1,"method":"tools/list"}index_constituents — Current constituents of a major US or developed-markets equity index — ticker, name, GICS sector, and weight — sourced from the matching iShares index-tracking ETF's daily holdings file (the closest free, point-in-time proxy for official index membership and weights; S&P/Russell do not publish those for free). Answers "what's in the S&P 500 right now", "top holdings of the Russell 2000 by weight", "which sectors make up the S&P MidCap 400". Cash, collateral and futures positions the ETF holds are excluded here — use ishares_etf_holdings for those.ishares_etf_holdings — Full reported holdings of one of six iShares index-tracking ETFs (IVV, IJH, IJR, IWB, IWM, EFA) as of the fund's own "as of" date — every position including cash, collateral and futures, each labeled with its asset class so they are never silently mixed in with equities. Answers "what does IVV actually hold today", "how much cash does this ETF carry". For just the equity index membership, use index_constituents instead.constituent_changes — Dated additions and removals from the S&P 500, sourced from Wikipedia's maintained "Historical components of the S&P 500" table (every S&P-announced swap since 1963, each with its effective date, the ticker/company added, the ticker/company removed, and the stated reason). Answers "what changed in the S&P 500 in 2024", "when was X removed from the S&P 500 and what replaced it". Only sp500 is covered — the iShares-backed indexes above have no equivalent public, dated changes table.Code samples (curl / TypeScript / one-click client install), schemas, and the live playground are on the pack page:
https://pipeworx.io/packs/index-constituents/
Pipeworx is an open MCP gateway connecting AI agents to live data. pipeworx.io