eSUB API
eSUB is a cloud construction project management platform built specifically for commercial subcontractors across the electrical, HVAC, plumbing, mechanical, masonry, concrete, structural steel, and drywall trades. This page is an independent design exercise that asks what a well-designed eSUB API could look like: the resources it would expose, the authentication it would need, and the workflows it could unlock. Below: a hypothetical endpoint design, the technical requirements a production implementation would face, the use cases programmatic access could serve, and where to start if your team needs this kind of access today.
This page is an independent analysis by Supergood of what a well-designed eSUB API could look like. It draws on publicly available information, vendor materials, and general integration experience in this category. Nothing on this page describes an existing eSUB product, and Supergood is not affiliated with or endorsed by the vendor. If the vendor offers an official API, we highly recommend it.
What is eSUB?
eSUB is a cloud construction project management platform built specifically for commercial subcontractors across the electrical, HVAC, plumbing, mechanical, masonry, concrete, structural steel, and drywall trades. Subcontractors use eSUB to capture daily reports and field documentation, manage RFIs and submittals, process change orders, control drawings and documents, track time and materials, and run job costing, connecting field crews to the back office through cloud and mobile apps. Fusion by eSUB is the company's modern connected-jobsite offering linking field personnel to back-office operations.
Core product areas include:
- Daily Reports and field documentation
- Project Management, RFIs, and Submittals
- Change Orders and Time & Materials tracking
- Document Control and drawing management
- Purchase Orders and Job Costing
- Time Management, Reporting, and Analytics
- Fusion by eSUB connected-jobsite tools
An API for a platform like this would naturally organize around its core data entities:
- Projects, Companies, Contacts, Users
- Daily Reports, Field Notes, Field Communications
- RFIs, Submittals, Drawings, Documents
- Change Orders, Purchase Orders, Time & Materials
- Time Entries, Labor, Job Costs, Cost Codes
The eSUB Integration Challenge
Subcontractors run mission-critical field-to-office workflows on eSUB daily, but turning portal- and mobile-driven workflows into API-driven automation is non-trivial:
- Mobile-first field data: Much of the most valuable data, daily reports, field notes, time entries, is captured in mobile apps and isn't exposed through a documented public REST API
- No documented public API: eSUB exposes integrations through partner connectors (QuickBooks Online, Autodesk BIM 360/Forge) rather than an open, self-serve developer API
- Partner ecosystem gates: BIM 360 and accounting flows ride on Autodesk Forge OAuth and pre-built connectors, requiring partnership setup before data access
- Project-by-project structure: Cost codes, document folders, and workflow states are configured per project, so generic integrations break across jobs
- Document and drawing workflows: RFIs, submittals, change orders, and field notes carry attachments and drawing markups that need careful upload/download handling
- Authentication complexity: Session-based logins and per-user entitlements complicate headless automation against the platform
What a eSUB API Could Look Like
If eSUB exposed a modern, general-purpose API, the integration challenges above suggest what it would need to get right. This is a design sketch, not documentation of anything that exists today:
- First-class authentication: session handling with support for MFA and enterprise sign-on where the platform uses them
- Consistent resources: normalized JSON schemas and pagination across the platform's core objects
- Reliable writes: idempotency keys and validation that mirrors the platform's own workflow rules
- Entitlement awareness: endpoints scoped to what each customer's licensing actually permits
The endpoint sketches, technical requirements, and use cases below flesh out this hypothetical design.
How AI agents could connect to software like eSUB: MCP servers for software without a public API →
Need This Kind of Access Today?
If your team needs this kind of access today, Supergood builds integrations on request, one customer at a time. We act at the direction of our customers, within the access they already hold. Customers bring their own accounts, licenses, and entitlements. If the vendor offers an official API, we highly recommend it.
- Schedule an Integration Assessment
A 30-minute session to review your product mix, licensing, and authentication model. - Scope the Integration
We design the access pattern around your workflows and entitlements. - Deploy with Monitoring
Go live with continuous monitoring as your platforms evolve.
Potential API Endpoints
Authentication
/authenticateWould authenticate to an eSUB account using username/password, or MFA and obtain a session token for downstream calls.
Projects
/projectsWould list projects with filters for company, status, and date range, including cost codes and document folder structure.
Field Operations
/daily_reportsWould retrieve daily reports and field notes with crew, weather, labor, and attachment details.
Field Operations
/create_daily_reportWould create a daily report or field note against a project with crew, hours, and supporting documents.
Project Documents
/rfisWould pull RFIs and submittals with status, assignment, due-date, and attached drawing markups.
Change Management
/create_change_orderWould submit a new change order against a project with cost items, markups, and approval routing.
Use Cases
Sync project and field data into the back office
- Pull projects, daily reports, and field notes from eSUB into a central warehouse - Stream labor, time, and material entries to job-costing and ERP systems - Reconcile crew and contact records across projects for unified reporting
Automate RFI and submittal workflows
- Pull open RFIs and submittals with due dates and assignments for tracking dashboards - Push new RFIs and submittal responses without portal clicks - Route overdue items and approvals to project managers automatically
Reconcile change orders and job costs
- Sync change orders, purchase orders, and time & materials into accounting and analytics - Match labor and material costs against project cost codes - Surface change-order revenue and pending approvals to finance workflows
Keep documents and drawings in sync
- Mirror document control folders and drawing markups into a DMS or BIM environment - Link field notes, RFIs, and change orders to plans and models - Trigger downstream notifications when drawings or documents change
Technical Requirements
Authentication
Would require username/password and MFA with managed session handling
Connectivity
Would build on authenticated web and mobile flows plus partner connectors (QuickBooks Online, Autodesk Forge/BIM 360) where exposed by the account
Response format
Normalized JSON across Projects, Daily Reports, RFIs, Submittals, Change Orders, and Time Entries
Rate limits
Adaptive throttling tuned to your account to avoid platform-side limits
Session management
Would need automatic session refresh, MFA replay handling, and credential rotation
Data freshness
Near real-time pulls for daily reports, RFIs, and change orders with optional scheduled batch syncs
Security
Encrypted credential vault, scoped access tokens, SOC 2-aligned controls, and audit logging
Webhooks
Event-style callbacks for new daily reports, RFI status, submittal updates, and change-order approvals
Latency
Design target: sub-second reads on cached entities; multi-second writes when posting field reports and change orders
Throughput
Design target: horizontally scaled workers sized to multi-project, multi-crew volume
Reliability
Retry, backoff, and idempotency keys for change orders, time entries, and document uploads
Versioning
Clear versioning and change management would matter as eSUB evolves
Frequently asked questions
Yes. Daily reports, field notes, time entries, and field communications captured in the eSUB mobile apps are exposed through the same normalized API surface, so field-to-office data sits alongside project and document entities.
Availability of official interfaces varies by product, plan, and licensing. Many platforms in this category gate access behind partner programs or paid modules, and there is often no broadly available, self-serve public API. Check the vendor's developer resources for current offerings.
The hard parts would be authentication (MFA, session management, enterprise controls), consistent schemas across the platform's products, and write semantics that reconcile the way the platform's own workflows do.
No. This page is an independent analysis by Supergood and is not affiliated with, sponsored by, or endorsed by the vendor. All product names and trademarks belong to their respective owners and are used for identification only. Nothing here documents an actual eSUB product or service.
Supergood acts at the direction of its customers, within the access those customers already have. We respect each customer's agreements with their software vendors, and how those agreements apply to a customer's use is a determination the customer makes. If the vendor offers an official API, we highly recommend it.
Supergood builds managed API access to enterprise software for customers on request, scoped to each customer's own licensing and entitlements. If your team needs programmatic access to a platform like this, schedule an integration assessment to discuss options.