OpenTwin · NestCode Property Standard · SeekYourNest

Every building has a record.
NestCode makes it readable.

NestCode is an open standard that defines how property data is structured, shared, and verified — maintenance history, documents, governance records, and a single health score. One format that works for housing societies, banks, insurers, and AI systems alike.

NESTCODE™
PROPERTY PASSPORT
Building Prestige Park, 4B
City Bengaluru, IN
NestScore™ 812 / 1000
Band EXCELLENT
Docs verified 11 / 12
Maintenance 94% SLA
Dues outstanding ₹ 0
Schema RFC-0001 v0.3
ID: hin:v1:IN:7e3cf2a148b9d0c4
c54fa8312e90b1d7
01

What lives inside a Property Twin

Defined by RFC-0001 through RFC-0007 and extended by 31 further RFCs.
Data layer What it contains RFC Who reads it
Identity NestCode ID (SHA-256 of geocoded address), building name, address, type, year built, total units RFC-0001, 0008 All consumers
Assets & Devices Lifts, generators, pumps, CCTV, fire systems — each with serial, last-service date, warranty expiry, IoT health status RFC-0002, 0003 Maintenance teams, insurers
Documents Sale deed, RERA certificate, OC, CC, building plan, NOC (bank / fire / airport), insurance policies, encumbrance certificate — 28 document types RFC-0004, 0037 Banks, lawyers, buyers
Legal & Revenue Title chain, mortgage liens, power of attorney, advocate-attested documents with bar council ID, Khata (Karnataka), Pattas (TN), property tax assessment, zone classification, FSI/FAR RFC-0037, 0038 Banks, government, lawyers
Residents & Staff Household profiles (PII-isolated), tenancy records, staff roster, background-verified credentials (W3C VC) RFC-0005, 0021, 0031 Society management, security
Financial history Maintenance charge ledger, due/paid history per unit, utility dues, penalty record, escrow balance, ISO 20022 payment messages RFC-0006, 0014 Banks, auditors, buyers
Governance AGM minutes, poll results, board elections, bylaw amendments — HMAC-chained, quorum-verified, regulator-queryable RFC-0018, 0023 Regulators, residents, courts
Operations Work orders, complaint lifecycle, gate passes, parcel custody, vehicle registry, facility bookings, emergency protocol, helpdesk SLA RFC-0024–0029 Society management, residents
Predictive data NestBrain ML failure-probability scores per asset, maintenance forecasts, community benchmarks against comparable buildings RFC-0030 Insurers, maintenance vendors
NestScore™ Computed health score 0–1000, factor breakdown, score history, band classification RFC-0014 Banks, insurers, buyers
02

NestScore™ — your building's financial health in one number

Defined by RFC-0014. Range 0–1000. Like a CIBIL score, but for the building itself.
# Factor Weight What raises the score What lowers the score
F1 Maintenance Compliance 35% AMC coverage across all major assets, work orders closed within SLA, no overdue preventive schedules Open work orders past SLA, expired AMC contracts, assets with no service record in 12 months
F2 Financial Obligations 25% Zero outstanding maintenance dues, utility charges settled monthly, no pending penalties Dues outstanding >30 days for any unit, partial payments, penalty accumulation
F3 Document Completeness 20% All 28 document types present and not expired, critical documents (OC, RERA, title deed) verified Missing or expired documents, especially OC / RERA cert / fire NOC / insurance
F4 Asset Condition 12% IoT sensors reporting healthy, assets within warranty, energy efficiency certificates current IoT devices past calibration date, assets outside warranty with no replacement plan
F5 Governance Compliance 8% AGMs held on schedule, quorum met, bylaws registered, election records present Missed AGMs, no quorum record, society operating under lapsed bylaws
Band Score range Meaning Practical benefit
Poor 0 – 250 Significant document, dues, or maintenance gaps Loan applications likely rejected; insurance rated at maximum premium
Fair 251 – 450 Partial compliance; some documents or dues outstanding Limited financing options; insurers may request physical inspection
Good 451 – 650 Core requirements met; minor gaps remain Standard mortgage terms; moderate insurance premium
Excellent 651 – 850 All documents verified; dues clean; maintenance on schedule −12% insurance premium (pilot); bank pre-approval within one business day
Elite 851 – 1000 Predictive maintenance, IoT-monitored, governance exemplary 4-hour bank pre-approval; best available insurance rates; smart-city integration
03

Who uses NestCode

The same standard serves all parties. One API call returns the full twin.
Audience Primary use case What NestCode enables Key RFCs
Housing Society (RWA) Day-to-day operations: maintenance, governance, collections Machine-readable AGM records, automated dues tracking, predictive asset maintenance schedules, gate pass and parcel management, society governance audit trail 0023, 0018, 0030, 0025
Builder / Developer Handing over a completed project to a society RFC-0034 Property Handover Protocol: standardised snag list with photo hashes, defect liability period tracking, OC milestone verification, common-area inventory schema that both parties sign off on 0034, 0004, 0015
Bank / NBFC Loan against property, mortgage, project finance Single API call returns maintenance compliance, full document set, dues history, and NestScore. Elite band → 4-hour pre-approval. Eliminates physical document collection for standard LAP transactions 0014, 0004, 0037, 0010
Insurer Property and society insurance pricing Live NestScore replaces questionnaire-based underwriting. Predictive maintenance data reduces claim frequency estimates. RFC-0030 NestBrain failure probability feeds directly into actuarial models 0014, 0030, 0027
Resident / Buyer Verifying a property before purchase or tenancy Read-only consent-scoped access to NestScore, document status, dues history, and governance records. Portable rental credit score (RFC-0021) moves with the tenant across properties 0010, 0014, 0021
Government / ULB Property registration, municipal records, smart-city data NestCode ID printed on title deeds creates a permanent machine-readable link. RFC-0022 Smart City Aggregate provides anonymised urban metrics (k-anonymity ≥50). RFC-0038 aligns with Khata, property tax, and municipal record schemas 0008, 0022, 0038
AI Agent / PropTech Answering questions about any property in natural language RFC-0011 MCP Tool Registry: 10 standard tool shapes that work identically on Claude, GPT-4o, and Gemini. One implementation covers all compliant platforms. Real property context, not stale training data 0011, 0017, 0036
04

The Standard: 38 RFCs, Apache 2.0

Anyone can read, implement, or contribute. Full corpus at nestcode.seekyournest.com.

NestCode is defined by 38 open Request for Comments documents, governed by SeekYourNest Technologies and an open contributor community. The standard is released under Apache 2.0 — free to read, implement, fork, and build upon. Certification is self-attested at Level 1 at no cost.

RFC Title One-line summary
RFC-0001–0007 Digital Twin Core Canonical entity schemas: Home, Assets, Devices, Documents, People, Financial Aggregates, Property Passport
RFC-0008 NestCode ID SHA-256 of geocoding-normalised address. Self-computable. Format: hin:v1:{CC}:{32hex}
RFC-0010 Consent & Data Exchange EdDSA consent tokens, 20-scope vocabulary, 60-second revocation. Governs every data share between parties
RFC-0014 NestScore™ Property health score 0–1000. Five weighted factors. ISO 20022 payment message integration for financial layer
RFC-0015 Verifiable Credentials did:opentwin DID method. W3C VC 2.0 and SD-JWT. Enables EUDI Wallet compatibility and W3C Verified Issuer status
RFC-0018, 0023 Community Twin & Governance Society structure, bylaws, shared infrastructure. AGM, elections, polls: all HMAC-chained and regulator-queryable
RFC-0021 Rental & Tenancy Full tenancy lifecycle. PII-isolated tenant profiles. Portable rental credit score that moves with the tenant
RFC-0030 Predictive Maintenance NestBrain ML failure-probability output schema. Community benchmarks. AI-generated ops digest format
RFC-0034 Property Handover Builder-to-society transition: snag list with photo evidence hashes, defect liability period, OC milestone tracking
RFC-0037 Legal & Encumbrance Title chain, EC, mortgage lien, POA, advocate-attested documents with bar council ID + digital signature, notarisation proof
RFC-0038 Municipal Records & Revenue Khata (KA), Pattas (TN), property tax assessment, NA order, zone classification, FSI/FAR, building completion certificate, CLU
RFC-0011 MCP Tool Registry 10 standard AI tool shapes. One implementation works on Claude, GPT-4o, Gemini. Real property context for every query

Full corpus of all 38 RFCs with schemas, conformance tests, and SDK references: nestcode.seekyournest.com

05

Get started

For housing societies & RWAs
Register your building on NestCode.

Any housing society can create a NestCode twin on SeekYourNest at no cost. Your building gets a NestCode ID, a live NestScore, and a digital passport that banks and insurers can read directly — no paperwork, no third-party verification calls.

For developers & proptech companies
Implement the standard. Reach every compliant platform.

Level 1 certification is self-attested and free. Implement RFC-0001–0007, run the open-source conformance suite, and display the NestCode Compatible badge. TypeScript and Python SDKs available. Kotlin, Swift, Java, Go, and Rust bindings in progress.