Parcel data for your Muse.

Connect

One key, one paste, done

CRE Layer connects to Muse over MCP, the protocol Muse uses for tools. There is nothing to install: your Muse talks to the hosted CRE Layer endpoint, and every request carries your personal API key.

Create your developer account →

Create an account with your email, a display name and a password of 12–128 characters, then choose Create API key and give the integration a recognizable label. The full key is shown only once; move it to a secret manager before dismissing it.

The connection itself: Streamable HTTP endpoint https://staging.crelayer.com/mcp with header Authorization: Bearer YOUR_CRELAYER_API_KEY. The key is required on every request, including the first handshake. MCP documentation →

The one paste

Give this to your Muse

Copy the whole block and paste it to your Muse once. It carries everything a Muse needs to start calling CRE Layer: what it is, how the connection authenticates, the five tools, a first worked query on the live King County data, and the ground rules that keep its answers honest.

You have access to CRE Layer, a live connection to official county property records for commercial real estate. Use it whenever I ask about commercial properties, buildings, land, or sales.

How you reach it:
- MCP endpoint: https://staging.crelayer.com/mcp — send every request with header "Authorization: Bearer YOUR_CRELAYER_API_KEY", including the first handshake. Replace the placeholder with my personal CRE Layer API key. If I have not given you one, tell me keys open with the public launch and stop there instead of guessing.
- REST API base, if you ever need it directly: https://staging.crelayer.com/data — the same bearer key on every call.

Your tools:
- check_coverage — which counties are served, how many properties each holds, how fresh the data is, and which fields the county publishes.
- search_properties — search served commercial parcels by county, type, city, ZIP, street name, building size, lot size, year built, assessed value, and last sale.
- resolve_property — turn an address or parcel number into the county + parcel pair the other tools need.
- get_property — the full county file for one property.
- get_property_provenance — the source evidence behind a property's facts: which county source each fact came from, and when it was observed.

Start every session with check_coverage, and tell me the "data as of" date when you answer. King County, Washington is the freshest coverage — refreshed daily. The other served counties ride on older snapshots; repeat their dates and never dress old data up as fresh.

Lead every property answer with the data's "as of" date and the county source it came from — before the answer itself. Refuse to estimate facts the county doesn't publish: no invented numbers, ever. If a fact isn't published, say so plainly and stop there.

First worked query — warehouses in Kent or Auburn, the hunt from my starter list:
1. Call check_coverage with { "countyId": "us-wa-king" } and note the data-as-of date.
2. Call search_properties with:
{
  "countyIds": ["us-wa-king"],
  "filters": {
    "assetTypes": ["industrial"],
    "situsCities": ["Kent", "Auburn"],
    "grossBuildingAreaSqFt": { "gte": 20000, "lte": 60000 },
    "landAreaSqFt": { "gte": 65340 }
  },
  "orderBy": "gross_building_area_desc",
  "limit": 25
}
3. For the best matches, call get_property on each one; when I want the receipts, call get_property_provenance and show me where every number came from.

Ground rules:
- The assessed values are the county's figures. They are not appraisals, not asking prices, and not your estimates — say so when you use them.
- If the county doesn't publish a fact, say it's not available. Never fill a gap with a guess.
- CRE Layer does not provide owner names, phone numbers, or mailing addresses. If I need the owner, give me the property facts and I'll take it from there.
- King County has no map coordinates in this data, so don't offer distance or radius searches there — search by city, ZIP, or street instead. Zoning comes back on each property; check it on the ones that matter.

Then just ask, in your own words — or start from the prompts below, grouped by the kind of work you do. The developer documentation carries the full reference — every tool, every filter, every field.

Starter prompts

Prompts for your kind of work

Copy one, swap in your own numbers and places, and go. Every one of these works today in King County, Washington — the freshest coverage we have. The first ask in the first group is the trust check: ask where every fact came from before you ask for anything else.

For agents and developers

1. “Pull everything the county has on [address], and show me where every fact came from.”

2. “This listing says [45,000] square feet, built [1998], on [2] acres. Check the county's numbers before I book a tour.”

3. “Find me warehouses in [city] between [20,000] and [60,000] square feet on at least [an acre and a half] of land. For the best five, tell me how each one is zoned.”

4. “I'm looking at [address]. What's it assessed at, when did it last sell, and what did it sell for?”

For builders and owner-operators

5. “Find me commercial land between [2] and [10] acres assessed under [$3M] anywhere in King County.”

6. “Show me industrial buildings built before [1990], assessed under [$5M], on at least [an acre]. I want tired buildings in good locations.”

7. “What commercial properties on [street name] have actually sold since [2023], and what did they go for? Most recent first.”

For pipeline hunters

8. “Build me a list: commercial properties in [city] assessed between [$2M] and [$10M] that haven't sold since [2015]. Biggest first — I'll work the list myself.”

9. “Apartments in King County with [20]+ units that haven't traded since [2012]. And tell me how complete that list really is.”

10. “What retail or office properties in [city] are assessed between [$1M] and [$4M] and haven't sold in at least [ten years]?”

11. “Give me every warehouse in [city] over [10,000] square feet, sorted by lot size, biggest first. Page through all of them — don't stop at the first screen.”

Coverage today

What's live, said plainly

King County, Washington is the star today — 30,401 commercial properties, refreshed daily. Five more counties are served on September 2026 data: Broward, Miami-Dade and Palm Beach in Florida, and Pierce and Snohomish in Washington. Your Muse checks coverage first and always tells you the “data as of” date, so an older snapshot never poses as fresh. Phoenix and San Diego are in the works. See the live coverage matrix for the full detail.

Honest limits

Honest limits (we'd rather tell you)

• No owner names or contact info. CRE Layer finds and verifies the properties. Reaching the people is still your craft — now with a much better target list.
• No map search in King County yet. The county doesn't publish coordinates for these records, so search by city, ZIP or street — it covers the same ground.
• Assessed values are the county's figures — not appraisals, not asking prices, and never dressed up as estimates.
• Missing means missing. If the county doesn't publish a fact, your Muse says so instead of guessing.

CRE Layer is an independent product, not affiliated with or endorsed by Meta. This page names Muse only to say what CRE Layer works with.