Conformance witness · observation, not accusation · recomputable

Tool-surface change observed — bim.house

Endpoint: https://bim.house/mcp

Version string served, unchanged across both observations: 1.0.0

Change first observed: 2026-10-27T07:40:08.907Z

Finding: CLASS_SUSPENDED

Surface expanded without a version change — clients pinned to this version approved a smaller set of tools than is now served.

What we observed

Two anonymous tools/list enumerations of the endpoint above, at different times.

The serverInfo.version string was byte-identical in both. The tool set was not.

Tools present in the later enumeration but not the earlier (4):

• build_on_land
• get_land_listing
• list_land_listings
• probe_land

Tools present in the earlier enumeration but not the later (15):

• admin_set_site_context
• delete_zoning_rule
• get_build_plan
• get_houki_rules
• get_site_context
• list_contractors
• list_incomplete_addresses
• match_contractors
• place_in_house
• place_order
• register_contractor
• set_forkable
• set_site_context
• update_house
• upsert_zoning_rule

Why this may matter to your users

A client that pinned 1.0.0 and reviewed the tool list at

pin time is, today, being served a different list under the same version string. Gateways

and MCP hosts that cache an approved tool set per version will not re-request approval,

because from their side nothing announced a change.

Verify this yourself

This is a plain MCP handshake. No credentials, nothing of ours required:

curl -s -X POST 'https://bim.house/mcp' \
  -H 'Content-Type: application/json' \
  -H 'Accept: application/json, text/event-stream' \
  -H 'MCP-Protocol-Version: 2025-06-18' \
  -d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2025-06-18","capabilities":{},"clientInfo":{"name":"check","version":"1"}}}'
# then, with the returned Mcp-Session-Id:
curl -s -X POST 'https://bim.house/mcp' \
  -H 'Content-Type: application/json' -H 'Accept: application/json, text/event-stream' \
  -H 'MCP-Protocol-Version: 2025-06-18' -H 'Mcp-Session-Id: <id>' \
  -d '{"jsonrpc":"2.0","id":2,"method":"tools/list","params":{}}'

Our surface hashes over the sorted tool names plus sorted input-schema property names:

If your own enumeration disagrees with the later hash, we are wrong and we want to hear it.

What this report does NOT say

• It does not allege a breach, compromise, or wrongdoing. An intentional untracked

deploy produces exactly this signal, and that is the most likely explanation.

• It does not assert the new tools are insecure. It asserts only that they appeared

under an unchanged version string.

• We enumerate anonymously, so tools behind authentication are invisible to us.

Absence from our view is not absence from your server.

• Two observations bound when the change was visible, not when it shipped.

Method

Unannounced periodic re-enumeration of a live MCP population — we ask the endpoint

directly on a schedule rather than waiting to be notified. Relevant because only

6.4% of live MCP servers have a working channel to announce a change at all

(69.1% never declare tools.listChanged; of those that do, most expose no

server-initiated stream to send it on). A change like the one above cannot reach a

notification-based monitor, which is why it is normally invisible.

*StillOS Digital Holdings — continuous conformance witness for MCP servers.*

*Report generated 2026-10-30T17:18:50.663Z from observations dated 2026-10-27T07:40:08.907Z.*