OpenProperty Specification

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OpenProperty Specification

Transparency for Every Home

Overview

OpenProperty is an open-source real estate transparency and property intelligence platform designed to create a more informed, verifiable, and ethical real estate ecosystem.

OpenProperty provides a modular foundation for applications that support buyers, renters, sellers, landlords, agents, inspectors, contractors, engineers, attorneys, municipalities, and other participants in property transactions.

The platform is designed around the principle that property information should be discoverable, understandable, traceable, and verifiable. It combines AI-assisted analysis, jurisdiction-aware regulatory guidance, public records, property documents, professional verification, and structured due diligence workflows.

OpenProperty includes specialized applications such as HouseLens for buyers and renters and TrustLens for sellers and property owners.

Mission

OpenProperty shall help transform real estate from a fragmented information system into a transparent property intelligence ecosystem.

The platform shall:

Make property information easier to discover
Identify missing information
Analyze property disclosures
Verify permits and compliance where data is available
Identify zoning and land-use considerations
Generate questions for sellers, landlords, municipalities, and professionals
Recommend appropriate inspections
Preserve evidence and source information
Support informed decision-making
Encourage complete and ethical disclosure
Reduce information asymmetry between transaction participants
Provide open-source infrastructure for future real estate applications

Design Principles

OpenProperty shall be designed around the following principles:

Transparency first
Verification over assumption
Location-aware intelligence
State law and local regulation priority
Comprehensive due diligence
Human-in-the-loop decision making
Explainable AI
Open-source development
Modular architecture
Vendor-neutral infrastructure
Interoperability
Data provenance
Privacy by design
Security by design
User ownership of information
No unnecessary vendor lock-in
Clear distinction between facts, claims, assumptions, recommendations, and unknowns

Core Modules

Property Identity Module

The Property Identity Module shall establish a consistent digital identity for each property.

The module shall support:

Property address
Geographic coordinates
Parcel identifiers
Tax identifiers where legally available
Property type
Current and historical use
Jurisdiction
Municipality
County
State
Relevant regulatory authorities
Property characteristics
Associated records

The property identity shall provide the foundation for all other OpenProperty analysis.

Jurisdiction Intelligence Module

The Jurisdiction Intelligence Module shall determine which laws, regulations, ordinances, disclosure requirements, and permitting requirements apply to a property.

The module shall identify:

State requirements
County requirements
Municipal requirements
Township requirements
Zoning jurisdiction
Building authority
Code enforcement authority
Rental authority
Environmental authorities
Other relevant governmental entities

All recommendations that depend on location shall reference the property’s jurisdiction.

Regulatory Intelligence Module

The Regulatory Intelligence Module shall organize applicable legal and regulatory information.

The module shall support:

State disclosure requirements
Property disclosure laws
Rental regulations
Zoning requirements
Building codes
Permit requirements
Occupancy requirements
Inspection requirements
Rental registration requirements
Local property regulations
HOA-related restrictions where applicable

The system shall maintain effective dates and source references where available.

OpenProperty shall not present generalized information as jurisdiction-specific legal advice.

Property Disclosure Module

The Property Disclosure Module shall provide a common framework for analyzing and managing property disclosures.

The module shall:

Accept disclosure documents
Extract structured information
Analyze disclosure completeness
Identify unanswered questions
Identify ambiguous responses
Identify contradictions
Compare disclosures with applicable requirements
Generate follow-up questions
Identify areas requiring professional review
Preserve source documents and evidence

The system shall distinguish information disclosed by a property owner from information independently verified by OpenProperty.

Missing Information Module

The Missing Information Module shall identify information that should be obtained before a user proceeds with a property transaction.

Potential missing information includes:

Property disclosures
Permit records
Inspection records
Certificates
Renovation documentation
Repair records
Contractor documentation
Zoning information
HOA documents
Rental documentation
Environmental records
Insurance-related information where legally available

The module shall generate actionable requests rather than simply reporting that information is missing.

Question Intelligence Module

The Question Intelligence Module shall generate customized questions based on the property, transaction type, jurisdiction, documents, records, and identified risks.

Questions may be directed to:

Sellers
Landlords
Listing agents
Property managers
Township officials
Municipal officials
County officials
HOA representatives
Inspectors
Engineers
Contractors
Attorneys
Other qualified professionals

Questions shall be prioritized according to:

Legal relevance
Safety implications
Financial significance
Transaction importance
Uncertainty
Potential property impact
Time sensitivity

Permit Intelligence Module

The Permit Intelligence Module shall analyze property improvements and determine which permits, inspections, or approvals may need to be investigated.

Supported improvements may include:

Additions
Sunrooms
Decks
Porches
Garages
Finished basements
Finished attics
Structural modifications
Electrical work
Plumbing work
HVAC installations
Roofing
Windows
Doors
Pools
Spas
Solar systems
Generators
Accessory dwelling units
Outbuildings
Other material improvements

The module shall identify records that should exist based on available information and applicable requirements.

An absent public record shall not automatically be interpreted as proof that work was unpermitted.

Zoning and Land Use Module

The Zoning and Land Use Module shall analyze property use and applicable land-use restrictions.

The module shall support:

Zoning classification
Permitted uses
Conditional uses
Setbacks
Lot requirements
Accessory structures
Home occupations
Rental restrictions
Short-term rental restrictions
Development restrictions
Easements where available
Variances
Special exceptions
Other land-use considerations

The module shall generate questions and verification requests when zoning information may affect the intended use of a property.

Public Records Module

The Public Records Module shall organize and analyze legally accessible public property information.

Supported records may include:

Property records
Tax records
Assessment records
Permit records
Zoning records
Code enforcement records
Occupancy records
Planning records
Public notices
Environmental records
Flood records
Municipal records
Other official records

Official records shall be distinguished from third-party sources.

Document Intelligence Module

The Document Intelligence Module shall process property-related documents.

Supported documents may include:

Disclosure forms
Inspection reports
Permit documents
Certificates
Contractor invoices
Repair records
Warranties
HOA documents
Lease agreements
Rental disclosures
Survey documents
Environmental reports
Zoning documents
Municipal correspondence

The module shall support:

OCR
Document classification
Information extraction
Entity extraction
Date extraction
Issue identification
Cross-document comparison
Missing information detection
Source preservation

Property Systems Module

The Property Systems Module shall organize information about major property systems.

Supported systems may include:

Foundation
Structure
Roof
Electrical
Plumbing
HVAC
Water heating
Sewer
Septic
Well
Drainage
Windows
Doors
Insulation
Fire safety
Chimneys
Appliances
Pools
Solar systems
Generators
Other material systems

The module shall track available documentation, reported conditions, inspection status, age where available, and unresolved questions.

Inspection Intelligence Module

The Inspection Intelligence Module shall determine which property systems may require evaluation by qualified professionals.

Recommendations may include:

General home inspection
Structural engineer
Licensed electrician
Licensed plumber
HVAC professional
Roofing professional
Chimney professional
Pest professional
Environmental professional
Mold professional
Septic professional
Well professional
Pool professional
Other appropriately qualified specialists

Each recommendation shall explain:

Why the inspection may be appropriate
What should be examined
What evidence triggered the recommendation
What professional qualification may be appropriate

AI recommendations shall not substitute for professional inspection or engineering judgment.

Risk Intelligence Module

The Risk Intelligence Module shall identify potential areas of concern.

Risk categories may include:

Structural risk
Water intrusion
Electrical risk
Plumbing risk
HVAC risk
Environmental risk
Permit risk
Zoning risk
Disclosure risk
Rental compliance risk
Documentation risk
Financial risk
Insurance-related risk
Data inconsistency
Unknown property condition

Each finding shall include available evidence, uncertainty, recommended actions, and source information.

Evidence and Provenance Module

The Evidence and Provenance Module shall preserve the origin and status of information.

The module shall track:

Source
Source type
Source URL where applicable
Document
Date obtained
Jurisdiction
Relevant record
Extracted information
Verification status
Confidence
User-provided claims
Professional verification

The system shall distinguish:

Verified facts
Official records
User-provided information
Seller-provided information
Landlord-provided information
AI-generated inference
Unverified claims
Unknown information

AI Intelligence Module

The AI Intelligence Module shall provide the reasoning and analysis layer across OpenProperty.

AI capabilities shall include:

Document analysis
Disclosure analysis
Regulatory analysis
Question generation
Risk detection
Permit reasoning
Zoning analysis
Inspection recommendations
Information comparison
Missing information detection
Due diligence prioritization
Natural language explanations
Report generation

AI-generated results shall include appropriate uncertainty indicators and supporting evidence where possible.

Due Diligence Module

The Due Diligence Module shall convert property intelligence into an actionable workflow.

The module shall:

Create due diligence checklists
Track questions
Track document requests
Track government requests
Track inspections
Track professional reviews
Track responses
Track unresolved issues
Track deadlines
Prioritize outstanding actions
Record user decisions

Transaction Intelligence Module

The Transaction Intelligence Module shall organize information throughout the transaction lifecycle.

Supported stages may include:

Property discovery
Initial evaluation
Disclosure review
Offer preparation
Contract period
Inspection period
Due diligence
Financing
Appraisal
Closing preparation
Post-closing property record

The module shall identify outstanding information and recommended actions at each stage.

Transparency Assessment Module

The Transparency Assessment Module shall evaluate how thoroughly a property has been documented and investigated.

Assessment factors may include:

Disclosure completeness
Permit verification
Renovation documentation
Inspection documentation
Public record verification
Zoning verification
Regulatory compliance
Unresolved questions
Missing documents
Professional verification

Transparency assessments shall never be represented as guarantees of property quality, legality, safety, or value.

Property Transparency Passport Module

The Property Transparency Passport Module shall provide a structured, shareable summary of verified property information.

The passport may include:

Property identity
Disclosure history
Permit history
Renovations
Inspections
Repairs
Certificates
Zoning information
Compliance information
Verification records
Supporting evidence
Outstanding questions

Information shall only be included according to appropriate authorization, provenance, privacy, and legal requirements.

Property History Module

The Property History Module shall organize available historical information about a property.

Potential information includes:

Previous disclosures
Permits
Renovations
Repairs
Inspections
Ownership changes where legally available
Property use changes
Code enforcement
Zoning changes
Other verifiable historical events

The module shall preserve source provenance and distinguish historical records from current conditions.

User and Access Control Module

The User and Access Control Module shall manage user identities and permissions.

Supported roles may include:

Buyer
Renter
Seller
Landlord
Agent
Inspector
Engineer
Contractor
Attorney
Administrator
Data provider
Developer

Permissions shall be based on the user’s authorized access to property information.

Privacy and Security Module

The Privacy and Security Module shall protect property and user information.

The module shall support:

Secure authentication
Authorization
Encryption in transit
Encryption at rest where applicable
Secure document storage
Access controls
Audit logging
Data minimization
Configurable retention
Secure deletion
Privacy-conscious AI processing

Reporting Module

The Reporting Module shall generate structured property intelligence reports.

Reports may include:

Property overview
Disclosure analysis
Regulatory requirements
Missing information
Permit findings
Zoning findings
Inspection recommendations
Risk findings
Questions
Document requests
Due diligence status
Evidence
Source references
Outstanding issues

Reports shall clearly distinguish verified information from unresolved information.

Notification and Workflow Module

The Notification and Workflow Module shall help users manage time-sensitive property tasks.

It may support:

Due diligence deadlines
Inspection scheduling
Document requests
Government requests
Follow-up reminders
Missing information alerts
Status changes
Transaction milestones

Interoperability Module

OpenProperty shall provide standardized interfaces for exchanging property intelligence.

The module shall support, where practical:

REST APIs
Structured property data
Structured document metadata
Geographic data
Evidence records
Property identifiers
Portable reports
Plugin interfaces
AI provider interfaces
Data source interfaces

Developer and Extension Module

The Developer and Extension Module shall provide documented interfaces for extending OpenProperty.

Developers shall be able to create:

Regulatory modules
AI modules
Public data connectors
Municipal integrations
Inspection systems
Document processors
Mapping integrations
Reporting systems
User interfaces
Professional services integrations

Extensions shall not require unnecessary modification to the OpenProperty core.

Specialized Applications

HouseLens

HouseLens shall provide the buyer and renter experience within the OpenProperty ecosystem.

HouseLens shall focus on:

Property due diligence
Disclosure analysis
Missing disclosure questions
Permit investigation
Zoning research
Inspection recommendations
Public record analysis
Seller and landlord questions
Township and municipal questions
Risk analysis
Transaction preparation

TrustLens

TrustLens shall provide the seller and property owner experience within the OpenProperty ecosystem.

TrustLens shall help users:

Prepare disclosures
Identify required documentation
Anticipate buyer questions
Verify renovations
Identify permits that should be investigated
Prepare inspection documentation
Gather municipal records
Identify potential compliance issues
Improve listing transparency
Prepare a property for due diligence

Optional Plugin Modules

Municipal Records Plugin

Provides connections to participating municipal and county record systems.

Capabilities may include:

Permit history
Certificates
Code enforcement records
Occupancy records
Zoning information
Property records

Permit Database Plugin

Connects OpenProperty to compatible permit databases.

Capabilities may include:

Permit searches
Permit status
Permit dates
Permit types
Inspection records
Final approvals

Zoning Data Plugin

Provides zoning information and geographic land-use data.

Capabilities may include:

Zoning classifications
Zoning maps
Ordinances
Setbacks
Permitted uses
Variances
Special exceptions

Property Tax Plugin

Provides compatible tax and assessment information.

Capabilities may include:

Assessments
Tax history
Property classifications
Tax status
Public assessment records

Environmental Data Plugin

Provides environmental and hazard information.

Potential data sources include:

Flood information
Environmental contamination records
Wetlands
Hazard areas
Radon information
Other legally accessible environmental datasets

HOA Intelligence Plugin

Analyzes HOA and condominium association information.

Capabilities may include:

Covenants
Restrictions
Fees
Assessments
Rules
Rental restrictions
Architectural restrictions
Meeting documents
Financial documents

Rental Compliance Plugin

Provides jurisdiction-specific rental analysis.

Capabilities may include:

Rental registration
Occupancy requirements
Rental inspections
Landlord requirements
Tenant protections
Security deposit requirements
Local rental restrictions

Insurance Intelligence Plugin

Provides property insurance research and risk analysis where legally and technically available.

Capabilities may include:

Insurance questions
Claims-related information where authorized
Property risk factors
Insurance documentation
Coverage considerations

Contractor Verification Plugin

Provides contractor and professional credential verification.

Capabilities may include:

License verification
License status
Credential information
Expiration dates
Disciplinary records where publicly available

Professional Services Plugin

Provides optional connections to qualified professionals.

Supported categories may include:

Inspectors
Engineers
Electricians
Plumbers
HVAC professionals
Roofers
Environmental professionals
Attorneys
Other qualified specialists

OCR Plugin

Provides OCR capabilities for scanned property documents.

Mapping Plugin

Provides geographic visualization of property information.

Capabilities may include:

Parcel boundaries
Zoning
Flood zones
Environmental conditions
Nearby infrastructure
Property context

Local AI Plugin

Allows OpenProperty installations to use locally hosted AI models.

The plugin shall support privacy-conscious deployments where property documents and personal information should remain within the user’s infrastructure.

External AI Provider Plugin

Allows users to configure compatible external AI services.

The plugin architecture shall make provider selection configurable and shall avoid requiring a single AI vendor.

Notification Plugin

Provides optional notification services for:

Email
Messaging
Calendar
Due diligence deadlines
Document requests
Transaction milestones

Export Plugin

Provides export functionality for:

Property reports
Transparency Passports
Due diligence records
Evidence packages
Question lists
Document inventories

Data Architecture

OpenProperty shall treat property information as structured, traceable data rather than isolated documents.

Core data entities may include:

Property
Parcel
Jurisdiction
Disclosure
Document
Permit
Inspection
Renovation
Repair
Regulation
Zoning Record
Public Record
Risk
Question
Request
Professional
Verification
Evidence
Transaction
User
Organization

Each entity should support provenance and verification status where applicable.

Verification Framework

OpenProperty shall use a verification framework that categorizes information according to its evidentiary status.

Possible statuses include:

Verified
Official Record
Professionally Verified
User Provided
Seller Provided
Landlord Provided
Reported
AI Inferred
Unverified
Conflicting
Unknown

The system shall not silently convert uncertain information into verified facts.

AI Governance

OpenProperty AI systems shall follow transparent and accountable design principles.

AI systems shall:

Identify the basis for important recommendations
Provide source references where available
Express uncertainty
Avoid fabricating records
Avoid inventing laws or regulations
Identify missing information
Recommend human verification when appropriate
Preserve user control
Avoid discriminatory decision-making
Avoid making unsupported legal conclusions

Ethical Real Estate Requirements

OpenProperty shall be designed to promote ethical real estate transactions.

The platform shall:

Encourage truthful disclosure
Identify potentially incomplete information
Help users discover material questions
Promote professional verification
Avoid assisting users in concealing property conditions
Avoid discriminatory property recommendations
Protect sensitive information
Maintain clear AI limitations
Support informed consent
Preserve evidence and provenance

Open Data and Public Information

OpenProperty shall prioritize lawful access to public information.

Integrations shall respect:

Government data policies
Terms of use
Licensing requirements
Privacy requirements
Copyright
Database rights where applicable
Rate limits
Access restrictions

OpenProperty shall not require unauthorized scraping or circumvention of access controls.

Security Requirements

OpenProperty shall implement security controls appropriate to the sensitivity of property and personal information.

Security requirements shall include:

Secure authentication
Least-privilege access
Secure session management
Encryption
Audit logging
Secure file handling
Input validation
API authentication
Dependency management
Security testing
Vulnerability reporting procedures

Privacy Requirements

OpenProperty shall minimize collection and retention of personal information.

Users shall have appropriate controls over:

Uploaded documents
Personal information
Property information
Sharing permissions
Retention
Deletion
External AI processing

Sensitive information shall not be shared with third-party services without appropriate authorization.

Interoperability and Vendor Independence

OpenProperty shall remain usable without dependence on a single commercial provider.

The system shall support interchangeable:

AI providers
Database systems
Public data sources
Mapping providers
Notification services
Document processors
Authentication systems

Where practical, interfaces shall use documented and portable formats.

Local-First Support

OpenProperty should support local-first deployments.

Local deployments should be capable of:

Storing property documents locally
Running compatible AI models locally
Processing documents locally
Maintaining local property records
Operating with limited external dependencies

External integrations may be enabled when users choose them.

Open Source Development

OpenProperty shall remain modular and accessible to developers.

Contributors may improve:

Core modules
AI systems
Regulatory knowledge
Data integrations
Document analysis
Inspection intelligence
Security
Privacy
User interfaces
Reporting
Accessibility
Internationalization

The project shall encourage collaboration among developers, real estate professionals, inspectors, engineers, attorneys, researchers, municipalities, and public-data contributors.

Future Property Intelligence Network

OpenProperty should evolve toward a property intelligence network in which authorized information can move with the property throughout its lifecycle.

Potential capabilities include:

Persistent property identity
Long-term property history
Verified renovation records
Permit history
Inspection history
Disclosure history
Compliance history
Evidence provenance
Property Transparency Passport
Authorized data sharing
Transaction intelligence
Post-closing property records

The system shall preserve privacy, authorization, provenance, and legal compliance as these capabilities develop.

Success Criteria

OpenProperty shall be considered successful when it enables users to:

Understand the legal context of a property
Identify applicable disclosure requirements
Analyze property disclosures
Detect missing information
Verify available public records
Investigate permits
Evaluate zoning considerations
Generate questions
Request appropriate documentation
Identify appropriate professional inspections
Track due diligence
Understand property risks
Trace findings to evidence
Distinguish verified information from unknown information
Make better-informed real estate decisions

Limitations and Professional Review

OpenProperty is an information and decision-support platform.

It does not replace:

Attorneys
Licensed inspectors
Engineers
Contractors
Appraisers
Insurance professionals
Government officials
Financial professionals
Other qualified professionals

Users should seek professional advice when required or appropriate.

AI-generated recommendations shall not be treated as professional determinations.

Specification Branding License (SBL)

Standard

Fully AGPL-3.0+ compliant system
Copyleft enforced for network deployments
Required attribution:
- Roxanne Ardary
- https://www.roxanneardary.com/

Optional

Specification Branding License (SBL)
- Attribution-free commercial deployment
- Pricing based on scale, usage, and deployment scope
- https://roxanneardary.com/openproperty/

License & Notice Requirements

OpenProperty is released under the GNU Affero General Public License v3.0 or later (AGPL-3.0+).

By contributing to this project, you agree that your contributions will also be released under this license.

Please note the following:

All contributions must comply with the AGPL-3.0+ terms.
Under Section 7 of the license, all redistributions, forks, and derivative works must preserve attribution to Roxanne Ardary and roxanneardary.com.
OpenProperty specifications are free to use with attribution. A Specification Branding License can be negotiated upon request.
The project’s notice.md file tracks attribution requirements and contributor acknowledgments.
Any update that adds new contributors or modifies attribution should also update notice.md.
When submitting a pull request, ensure that any new files maintain the attribution headers where applicable.
Network-deployed versions of this software must also remain fully AGPL-3.0+ compliant, including exposure of source code modifications when applicable under the license.

For full legal details, please refer to the AGPL-3.0+ license and the project’s notice.md file.

Notice – OpenProperty

Attribution Requirement: Under Section 7 of the AGPL 3.0+ license, all redistributions, forks, and derivative works, including network-deployed versions of this project, must provide attribution to Roxanne Ardary and roxanneardary.com.

Contributors

This file tracks contributors and their specific contributions to the project.

Roxanne Ardary, roxanneardary.com – March 10, 2026
Created the repository for OpenProperty. Developed the open-source AI platform integrating HouseLens and TrustLens for complete property transparency, guidance, and compliance.
[Add other contributors here] – [Date]
[Describe contribution in one sentence]

License – OpenProperty

This repository is licensed under the GNU Affero General Public License v3.0 or later (AGPL-3.0+).

Key Points:

You are free to use, modify, and distribute the code.
All redistributions, forks, and derivative works or network-deployed versions must also be licensed under AGPL-3.0+ and provide attribution to Roxanne Ardary and roxanneardary.com as required under Section 7 of the license.
The software is provided “as is,” without warranty of any kind.

For the full license text, see GNU AGPL-3.0 License.