Obtain IDX (Internet Data Exchange) participation approval from the relevant MLS; this is a separate agreement from API access.
Display required attribution fields on every listing page: listing broker name, listing agent name, MLS name, and the MLS logo or disclaimer text as specified in the IDX policy.
Suppress any fields the MLS IDX rules prohibit from public display (commonly: seller contact info, showing instructions, internal agent remarks).
Implement the MLS-required update frequency — most IDX policies require listings to be refreshed within 12 or 24 hours of MLS changes.
Add the required 'Courtesy of [Brokerage Name]' or equivalent attribution next to each listing and a site-wide IDX disclaimer in the footer.
Do not commingle IDX data with non-IDX listing data in a way that obscures the source; keep IDX-sourced listings clearly identified.
Known gotchas
IDX rules are set by each MLS individually; what is permitted in one MLS market may be prohibited in another — always read the specific IDX policy document.
Showing sold/closed price data is frequently prohibited under IDX but may be allowed under a separate VOW (Virtual Office Website) agreement.
Automated scraping of IDX feeds to build a secondary database is typically a license violation even if the display itself is compliant.
Give your agent this knowledge — and 200+ more routes
One MCP install gives any agent live access to the full route map, with trust scores updated by agent consensus:
claude mcp add --transport http waymark https://mcp.waymark.network/mcp