Technical Architecture & Statutory Engine Specifications

Inside ReconDesk

Every layer of matching, every compliance rule, every decision — explained.

103 Hardcoded Statutory Rules₹0 Financial Drift GuaranteePaise-Level Audit RigorZero AI Model Ingestion

Chapter 01 · Data Ingestion Architecture

Zero Column Remapping. Universal Accounting Ingestion.

ReconDesk eliminates the tedious spreadsheet preparation step. Upload raw client files directly from any software; our header detection engine auto-detects fields in under a second.

Any Accounting Software

Native support for Tally Prime, Tally ERP 9, Busy Accounting, Zoho Books, SAP, Oracle Financials, and custom Excel dumps.

Auto Header Mapping ✓

1-Second Portal Parser

High-speed parsing of massive GSTR-2B JSON and Excel dumps (10,000+ invoices in <1.2 seconds) with paise-level component split.

10k Rows in 1.2s ✓

1-Click GSTN OTP Fetch

Direct government portal integration. Enter client GSTIN, verify with OTP, and pull official GSTR-2B data automatically without manual downloads.

Direct Portal Sync ✓

IMS & E-Invoice Scanner

Automated Accept / Reject / Keep on Hold recommendations for the Invoice Management System + 64-character IRN validation.

IMS Action Writeback ✓

Chapter 02 · Deterministic Multi-Phase Matcher

The 5-Level Matching Architecture

Standard Excel VLOOKUP fails because invoice formatting is inherently messy. ReconDesk resolves invoice discrepancies through 5 progressive deterministic tiers with ₹0 financial delta.

INVOICE_PAIR_DISSECTIONActive Level: L2

GSTR-2B (Portal JSON):

27AAACT0012P1ZR · INV/2026/0941 · ₹57,354.20

Purchase Register (Tally):

27AAACT0012P1ZR · 941 · ₹57,354.20

✨ L2 Normalized: Stripped '/2026/' prefix and leading zeros. Financial Delta: ₹0.00.

Statutory Rigor

How L2 Operates

Suppliers frequently file with prefixes like 'INV/26/', '2026-', or strip leading zeroes ('00941' vs '941'). ReconDesk extracts the core numerical and alphanumeric token, bridging the format gap without human intervention.

Zero Loss of Audit TrailReviewer Timestamp Attached

Chapter 03 · Statutory Intelligence

The 103+ Statutory Rules Codex

Every tax check in ReconDesk is directly mapped to the Central Goods and Services Tax Act, 2017 and CGST Rules. Search and inspect the comprehensive statutory rules catalogue below.

Showing 21 core statutory verification handlers● 100% Audit-Grade Traceability

MAT_001CGST Act Section 16(2)(aa) r/w Rule 36(4)

GSTR-2B Portal Reflection Verification

Trigger Condition: Invoice details must be communicated to recipient in Form GSTR-2B generated under Rule 60(7).

ReconDesk Action: Verifies invoice presence in supplier-filed GSTR-2B. Invoices not in 2B are quarantined to prevent wrongful GSTR-3B claims.

Tagged as 'Eligible ITC' or 'Missing in 2B — Pending Supplier Filing'.● Active in Pipeline

MAT_002CGST Act Section 16(4)

Annual Statutory ITC Claim Cut-Off Tracker

Trigger Condition: ITC in respect of any invoice or debit note cannot be claimed after 30th November following the end of financial year or annual return filing.

ReconDesk Action: Monitors invoice dates against the November 30 statutory deadline. Flags prior-year unbooked credits approaching expiration.

Section 16(4) Expiration Risk Alert with remaining calendar days countdown.● Active in Pipeline

MAT_003CGST Act Section 16(2)(a) r/w Rule 48(4)

Possession of Tax Invoice & QR IRN Verification

Trigger Condition: Taxpayer must be in possession of valid tax invoice/debit note with mandatory 64-character IRN for applicable B2B suppliers.

ReconDesk Action: Validates supplier E-Invoice IRN schema and matches invoice date with tax invoice issuance date.

IRN Status: Verified / Non-Applicable.● Active in Pipeline

MAT_004CGST Act Section 16(2)(c)

Tax Actually Paid to Government Verification

Trigger Condition: Tax charged in respect of supply must be actually paid to the Government by the supplier in cash or eligible ITC.

ReconDesk Action: Cross-checks supplier GSTR-3B filing status indicators in portal metadata to identify non-compliant vendors.

Supplier GSTR-3B Filing Compliance Flag: Active / Defaulter.● Active in Pipeline

R37_001CGST Rules Rule 37 r/w Section 50(1)

180-Day Supplier Payment & Section 50(1) Interest Calculation

Trigger Condition: Recipient fails to pay supplier value of supply plus tax within 180 days from invoice date.

ReconDesk Action: Calculates exact 18% per annum interest liability from invoice date; computes proportionate partial payment reversals.

Rule 37 Reversal Schedule exported in GSTR-9C Workpaper Sheet 4.● Active in Pipeline

R37_002CGST Rules Rule 37(4) Proviso to Section 16(2)

Rule 37 Reclaim on Subsequent Supplier Settlement

Trigger Condition: Recipient makes payment of value of supply plus tax to supplier after earlier reversal.

ReconDesk Action: Automatically allows reclaim of previously reversed ITC in GSTR-3B Table 4(A)(5) upon detecting payment date.

Rule 37 Reclaim Ledger entry with voucher linkage.● Active in Pipeline

R37_003CGST Rules Rule 37A

Supplier GSTR-3B Non-Filing Reversal Tracker

Trigger Condition: Supplier filed GSTR-1 but failed to furnish Form GSTR-3B by 30th September following the end of financial year.

ReconDesk Action: Flags defaulting supplier GSTINs for mandatory Rule 37A reversal by 30th November, and tracks re-credit upon filing.

Rule 37A Defaulting Supplier Notice & Reclaim Audit Log.● Active in Pipeline

SEC17_001CGST Act Section 17(5)(a) & (aa)

Motor Vehicles & Passenger Transport Credit Scanner

Trigger Condition: Motor vehicles for transportation of persons having approved seating capacity of ≤ 13 persons, unless used for specified taxable purposes.

ReconDesk Action: Scans purchase ledgers for HSN Chapter 8703 / vehicle lease expenses and advises CA to block in GSTR-3B Table 4(B)(1).

Blocked Credit Advisory citing Section 17(5)(a).● Active in Pipeline

SEC17_002CGST Act Section 17(5)(b)(i) & (ii)

Food, Beverages, Outdoor Catering & Club Memberships

Trigger Condition: Supply of food and beverages, outdoor catering, beauty treatment, health services, club memberships, and life/health insurance.

ReconDesk Action: Detects HSN 9963 / 9972 catering and corporate subscription bills; restricts claim before GSTR-3B preparation.

Ineligible ITC flag with statutory exempt override notes.● Active in Pipeline

SEC17_003CGST Act Section 17(5)(c) & (d)

Works Contract for Immovable Property Construction

Trigger Condition: Works contract services supplied for construction of immovable property (other than plant and machinery) when capitalized.

ReconDesk Action: Scans HSN 9954 contractor invoices and cross-checks asset capitalization tags to flag blocked construction credit.

Immovable Property Capitalization Warning in audit summary.● Active in Pipeline

SEC17_004CGST Act Section 17(5)(h)

Goods Lost, Stolen, Destroyed, Written Off or Gifted

Trigger Condition: Goods lost, stolen, destroyed, written off or disposed of by way of gift or free samples.

ReconDesk Action: Identifies inventory write-down vouchers and promotional sample distributions to compute mandatory credit reversal.

Section 17(5)(h) Stock Write-Off Reversal Schedule.● Active in Pipeline

R88D_001CGST Rules Rule 88D r/w Form GST DRC-01C

GSTR-3B vs 2B Dual-Threshold Notice Trigger Pre-Check

Trigger Condition: ITC availed in GSTR-3B exceeds ITC available in GSTR-2B by more than 10% / 20% and ₹25,00,000.

ReconDesk Action: Pre-calculates net variance across IGST, CGST, SGST before 3B submission; triggers alert if thresholds are breached.

One-Click DRC-01C Explanatory Reply Draft with statutory citations.● Active in Pipeline

R88C_001CGST Rules Rule 88C r/w Form GST DRC-01B

GSTR-1 Outward Tax vs GSTR-3B Table 3.1 Liability Check

Trigger Condition: Tax payable declared in Form GSTR-1 exceeds the liability declared in Form GSTR-3B Table 3.1(a).

ReconDesk Action: Compares outward registers against 3B tax payments; auto-drafts DRC-01B Part B reply citing earlier period excess tax.

Form GST DRC-01B Part B Response Narrative.● Active in Pipeline

RCM_001CGST Act Section 9(3) & Section 9(4) r/w Table 3.1(d)

Inward Reverse Charge GTA & Legal Services Segregation

Trigger Condition: Supplies received from Goods Transport Agencies (GTA), legal advocates, or security agencies subject to reverse charge.

ReconDesk Action: Segregates RCM inward supplies to ensure liability is paid in cash in Table 3.1(d) and concurrently claimed in Table 4(A)(3).

RCM Tax Head Cash Payment & ITC Claim Reconciliation.● Active in Pipeline

RCM_002CGST Act Section 31(3)(f) & (g)

RCM Self-Invoice & Voucher Number Validation

Trigger Condition: Recipient liable to pay tax under Section 9(3)/9(4) must issue payment voucher and self-invoice on date of receipt.

ReconDesk Action: Checks for corresponding payment voucher entries in accounting ledgers for all inward RCM claims.

RCM Self-Invoice Compliance Schedule.● Active in Pipeline

G1M_001CGST Act Section 37 r/w Rule 59

B2B Outward Invoice Omission Diagnostic

Trigger Condition: B2B sales invoice entered in books but omitted in Form GSTR-1 Table 4A/4B.

ReconDesk Action: Flags missing sales records to prevent recipient ITC loss and downstream commercial disputes.

G1M1 Missing B2B Outward Schedule.● Active in Pipeline

G1M_002CGST Rules Rule 59(2) Table 12

Tax Rate Discrepancy & HSN Rate Drift

Trigger Condition: Tax rate billed in accounting software (e.g. 18%) differs from GSTR-1 declaration (e.g. 12%).

ReconDesk Action: Detects tax rate differences per line item and computes differential tax liability before filing lock.

G1M3 Differential Tax Rate Audit Log.● Active in Pipeline

G1M_003CGST Rules Rule 59 Table 5 & Table 7

B2B vs B2CL / B2CS Cross-Classification Check

Trigger Condition: Registered B2B invoice incorrectly declared in Table 5 (B2CL) or Table 7 (B2CS retail).

ReconDesk Action: Isolates invoices with recipient GSTIN filed under unorganized retail buckets, generating reclassification schedules.

G1M5 Reclassification Table for GSTR-1A amendment.● Active in Pipeline

G1M_004CGST Rules Rule 59(2) Table 13

Table 13 Document Serial Sequence & Cancellation Audit

Trigger Condition: Gaps or overlaps in serial numbering of tax invoices, credit notes, and cancelled documents issued during the month.

ReconDesk Action: Validates sequential numbering from start to end number and tallies total issued vs cancelled counts.

Table 13 Document Sequence Audit Certificate.● Active in Pipeline

G9C_001CGST Act Section 44 r/w Rule 80(3)

Table 8A vs Table 8B/8C 12-Month Period Rollup

Trigger Condition: Annual reconciliation of ITC reflected in GSTR-2B (Table 8A) against ITC availed in GSTR-3B (Table 8B & 8C).

ReconDesk Action: Compiles all 12 monthly GSTR-2B returns against purchase ledgers, isolating timing differences causing Table 8D gaps.

Table 8D Reconciliation Statement with zero unverified variance.● Active in Pipeline

G9C_002CGST Act Section 44 Table 8 Workpapers

Supplier-Wise PAN Rollup & Cross-State Branch Aggregation

Trigger Condition: Multi-state suppliers billing across different branch GSTINs under the same Corporate PAN.

ReconDesk Action: Rolls up all transactions by 10-digit PAN, matching total financial year turnover and eligible tax credits.

Supplier PAN Workpaper Sheet 2 in GSTR-9C Audit Pack.● Active in Pipeline

Chapter 04 · Outward Supply & Revenue Reconciliation

GSTR-1 Outward Diagnostics (G1M1–G1M10)

Ensure outward tax liabilities match accounting ledgers before monthly filing locks. ReconDesk executes 10 diagnostic tests across B2B, B2CL, export LUT, and document sequences.

G1M1 → G1M10 Diagnostic MatrixTable 4 to 13

G1M1 / G1M2: Inward B2B sales in books missing in GSTR-1 or vice-versa.
G1M3 / G1M4: Tax rate drift (e.g. 18% billed in books vs 12% declared on portal).
G1M5 / G1M6: B2B invoice wrongly classified under B2CL or B2CS unorganized retail.
G1M7 / G1M8: Export invoice with/without payment of tax vs shipping bill LUT mismatch.
G1M9 / G1M10: Credit note (CDNR) without original invoice linkage & Table 13 count gap.

GSTR-1A Mid-Month Window

Pre-Filing Amendment Recommendations

Before the monthly portal window locks on the 14th, ReconDesk generates a formatted amendment schedule so you can rectify supplier disputes in GSTR-1A before GSTR-3B liability is generated.

GSTR-1A Amendment Action ScheduleFY 2026–27

⚡ 3 B2B Invoices recommended for upward value amendment · ₹42,000 differential tax pre-calculated.

Eliminates Rule 88C DRC-01B outward liability intimations

Chapter 05 · Notice Defense System

Rule 88D Notice Shield & DRC-01B/C Drafter

Under Rule 88D, whenever ITC claimed in GSTR-3B exceeds GSTR-2B by >10% and >₹25 Lakhs, an automated DRC-01C intimation is generated by the GST portal. ReconDesk stress-tests your return before filing.

Rule 88D Dual-Threshold Stress-Tester

Drag the slider to test how ReconDesk monitors excess ITC claims against statutory thresholds.

Excess ITC Claimed in 3B:₹28.00 Lakhs

₹5 LakhsThreshold: ₹25 Lakhs₹60 Lakhs

Available ITC in 2B:₹1,20,00,000 (1.20 Cr)

Excess Percentage:23.3%

Dual-Threshold Status:🔴 DRC-01C STATUTORY TRIGGER

FORM_GST_DRC_01B_PART_B_REPLYStatutory Template

Reason 1: Excess liability / timing difference under Section 16(4)

"The differential ITC of ₹28.00 Lakhs pertains to inward supplies of previous tax periods in respect of which tax was deposited by suppliers but reflected in GSTR-2B of the current tax period. Workings are maintained and verified."

PDF & Word Export Ready

Chapter 06 · Annual Certification

GSTR-9C Multi-Sheet Audit Workbook Architecture

At financial year-end, manual 12-month reconciliation is a nightmare. ReconDesk rolls up all 12 monthly GSTR-2B returns against your annual purchase register into a ready-to-certify multi-sheet `.xlsx` workbook.

ANNUAL GSTR-9 TABLE 8 RECONCILIATION SCHEDULEFY 2025–26 ROLLUP

Table 8A (ITC available in GSTR-2B auto-drafted):₹5,78,94,200.00

Table 8B (ITC as per GSTR-3B Table 4(A)(5) availed):₹5,78,94,200.00

Table 8D Difference (8A − (8B + 8C)):₹0.00 (Zero Drift Certified)

Format: Multi-Sheet .XLSX & PDF Sign-Off Report● Formatted for Statutory Auditors

Chapter 07 · Practice Management & Audit Governance

Architected for CA Firm Workflows & Peer Review

Managing 50+ client GSTINs requires structured teamwork. ReconDesk provides multi-user firm accounts, audit locking, and automated communication tools.

Unlimited Team Seats

Invite article assistants, senior audit managers, and partners with role-based review permissions.

Multi-User Collaboration ✓

Finalize & Lock Runs

Once filed, partners can lock the run. Prevents accidental edits and ensures immutable records for ICAI peer review.

Immutable Audit Trail ✓

1-Click Supplier Notices

Auto-generate formal PDF letters and WhatsApp text for defaulting vendors with itemized missing invoice tables attached.

PDF & WhatsApp Export ✓

Permanent Data Purge

Export complete encrypted archives and permanently delete any client engagement records in 1 click upon audit completion.

Zero-Residual Purge ✓

Experience the Full Depth of ReconDesk Free

2 GSTINs are 100% free for 60 days with all 103+ statutory rules, multi-phase matching, and full audit workpapers unlocked.

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