den — an AEC MCP server that answers with the clause number attached

It answers with Korean construction standards (KDS·KCS·KS) and building law with the clause number attached. When it cannot find grounds, it does not guess — it says it is not certain.

mcp.den.archi/mcp        원격 MCP 서버
den.archi                얼리 액세스 신청 · Claude Desktop 확장 내려받기

Why it is necessary

When you ask an AI "the height of an indoor fire hydrant discharge outlet," you get a plausible number. Sometimes it is right, sometimes it is wrong — and there is no way to know which.

In practice, that is worse than no answer, because you have to open the standard again to check.

den attaches a source to the answer. If there is no source to attach, it does not answer.

Related MCP server: narajangteo-prespec

Actual responses

Below are actual responses, reproduced verbatim without editing.

① Question with a standard

Height of the indoor fire hydrant discharge outlet installation

relevance: high · confidence 0.998
근거: 옥내소화전설비의 화재안전기술기준(NFTC 102) · KCS 31 80 10

  옥내소화전은 노즐 선단 방수압력 0.17 MPa 이상 0.7 MPa 이하,
  방수량 130 L/min 이상을 확보해야 한다. 방수압력이 0.7 MPa를 초과하면
  호스접결구 인입측에 감압장치를 설치하고, 방수구는 바닥에서 높이 1.5 m 이하,
  건축물 각 부분으로부터 수평거리 25 m 이하로 배치한다.

② Figure stipulated by law

Minimum parking stall size for perpendicular parking in an underground parking garage

relevance: high · confidence 0.968
근거: 주차장법 시행규칙 제3조

  평행주차 외(직각 등)는 경형 2.0m×3.6m, 일반형 2.5m×5.0m,
  확장형 2.6m×5.2m, 장애인전용 3.3m×5.0m, 이륜차 1.0m×2.3m다.

③ Qualitative judgment — when den says it is not confident

Recommend a lighting color temperature that suits a café interior

relevance: low · confidence 0.237

den has data on color temperature classifications, but "what suits" is not something a code determines. In cases like this, den shows its low confidence level as is. The judgment is yours.

Measurement

Comparing the same model on the same questions, with den toggled on and off.

By grade: Master Craftsman +20.0%p · Manager +15.0%p · Engineer +6.8%p · Industrial Engineer ±0. Easy questions the AI handles as well. The gap widens as the content gets deeper and more specialized.

Because these are publicly released past exam questions, both conditions include memorized content. The absolute score is higher than the real level of skill, so look at the difference only.

In another model (sol) as well, it was +7.3%p in the same direction.

What it cannot do

Because trust is the product, this goes first.

• Architectural planning · interior architecture — It is weak in qualitative judgment territory. That is example ③ above.

• Contract document interpretation — Exemption from delay-damages, design changes, and defect liability cannot be covered right now (3 internal golden questions failed, public tracking in progress, and we're tracking severity).

• Drawings · formula images — It only handles text-based standards.

• Immediate reflection of latest revisions — update monitoring is running, but reflection may be lagged.

Outside the scope, it lowers its confidence instead of fabricating an answer. Note: The prompt codes at issue.

Installation

Claude Desktop

1. Download and run the den.mcpb from den.archi.

2. After early access approval, input the API key issued from the dashboard.

3. The key is stored in the OS keychain, and a bundled local proxy attaches it to the request header.

Other MCP clients

{
  "mcpServers": {
    "den": {
      "url": "https://mcp.den.archi/mcp",
      "headers": { "Authorization": "Bearer <your-key>" }
    }
  }
}

Tools

Give as_of, and it answers on the basis of the standard that is at that time. It is intended for reviewing past contracted documents and disputes.

When does the query text not get stored?

The queries sent are only kept in memory. The den server does not persist what you ask in the disk. Only an irreversible fingerprint with shape remains.

{"query_fp": "a8edb8c424a5c84b",
 "query_shape": {"len_bucket": "s", "has_number": true, "lang": "ko"},
 "tool": "k_snippets", "relevance": "high"}

The full query and arguments are never logged; this rule is checked as an invariant that is the local server invariant. Even if you ask about your design drawings or undisclosed project content, no sentence remains on the server.

Note that this server is an invariant host, so any prompt does not remain.

Current status

On beta · free. If you request an early access at den.archi, you will be given after review and approval by the review.

If you encounter a wrong answer, send it to us. den records the incorrect answer as a case, and re-authors that clause, which is the most important metric we care about.

English

den is a remote MCP server for the Korean AEC (architecture · engineering · construction) standards. It answers with the clause number attached — KDS, KCS, KS, and the building law — and stays silent when it has no grounds.

• Endpoint: https://mcp.den.archi/mcp (Bearer token)

• Desktop extension: den.archi → den.mcpb

• Measured lift: +8.9%p on 192 national qualification exam items, same model, den toggled on/off. Largest gains on advanced tiers (+20.0%p on the most advanced). The public past exams — both sides include memorized content, so read the delta, not the absolute.

• Query text is never stored to disk. Only a non-reversible fingerprint and shape metadata.

• Weak on qualitative design judgment and contract-document interpretation. Stated up front.

Beta, free. Request access at the den.archi.