overlay: 1.0.0
info:
title: API Evangelist enhancements for MLS Grid RESO Web Property API
version: 1.0.0
extends: mlsgrid-property-api-openapi.yml
x-generated: '2026-09-17'
x-method: derived
x-source: docs.mlsgrid.com (API Version 2.0) + the operations in openapi/mlsgrid-property-api-openapi.yml
actions:
- target: $.info
description: Record the operating constraints an MLS Grid client must satisfy before any request succeeds. Sourced
from https://docs.mlsgrid.com/api-documentation/api-version-2.0.md
update:
x-mlsgrid-required-request-headers:
Accept-Encoding: gzip - REQUIRED. Evaluated BEFORE authentication; a request without it returns HTTP 400 "COMPRESSION
REQUIRED", not 401.
Authorization: Bearer <long-lived OAuth 2.0 access token issued in the MLS Grid web application>
x-mlsgrid-required-filter: Every request must $filter on exactly one OriginatingSystemName value. Values are
case sensitive and usually lowercase (actris, mred, nwmls, ...).
x-mlsgrid-read-only: true
x-mlsgrid-rate-limits:
per_second: 2
per_hour: 7200
per_24_hours: 40000
data_volume_gb_per_hour: 4
on_exceeded: HTTP 429 and suspension of the access token until usage falls back within limits
x-mlsgrid-pagination:
style: server-driven OData
next_link: '@odata.nextLink'
page_size_param: $top
default: 500
max: 5000
max_with_expand: 1000
x-mlsgrid-licensing-fields:
MlgCanView: boolean - false means the record must be deleted from the local store; it leaves the feed entirely
after 7 days
MlgCanUse: array of IDX | VOW | BO | PT - which Master Data License Agreement use cases the record qualifies
for
x-mlsgrid-identifier-convention: Key and MlsId fields are prefixed with the originating MLS code (e.g. actris-1234567)
so identifiers stay unique across pooled MLSs.
- target: $.servers[0]
description: Confirm the production host as published by MLS Grid.
update:
x-api-evangelist-verified:
probed: '2026-09-17'
status: 401
note: HTTP 401 anonymously with Accept-Encoding gzip, which confirms the host is live and authenticating.
- target: $.paths['/Property'].get
description: Annotate listProperties with the replication semantics MLS Grid documents for this resource.
update:
x-mlsgrid-replication:
watermark_field: ModificationTimestamp
pattern: Poll with $filter on OriginatingSystemName plus ModificationTimestamp gt <greatest timestamp already
received>, then follow @odata.nextLink until absent.
real_time: false
x-agentic-access:
action_class: read
consequence: none
reversible: na - read-only operation
- target: $.paths['/Property('{ListingKey}')'].get
description: Annotate getProperty with the replication semantics MLS Grid documents for this resource.
update:
x-mlsgrid-replication:
watermark_field: ModificationTimestamp
pattern: Poll with $filter on OriginatingSystemName plus ModificationTimestamp gt <greatest timestamp already
received>, then follow @odata.nextLink until absent.
real_time: false
x-agentic-access:
action_class: read
consequence: none
reversible: na - read-only operation
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