Document & Contract Management V1: Core AP / GR / PO

1. Core Principle: Decision-Grade Document Layer

• Goal: We are not building a generic DMS or CLM. We are building a "decision-grade document layer".
• Philosophy: Documents exist solely to justify postings, approvals, accruals, and clearings. Everything else is noise.
• Outcome: A rigorous Document Graph that interlinks evidence for audit-grade financial decisions.

2. Canonical Document Types (V1)

You need exactly these four types, no more.

A) Invoice (Refinement)

• Existing: PDF, extracted structure, line items, matching links.
• New Requirements:
  • Immutable Snapshots: Stored state of the invoice at the exact moment of posting/approval.
  • Versioning: Handling revised invoices and credit notes (linked to original parent).
  • Graph Linkage:
    • invoice_line ↔ po_line
    • invoice_line ↔ gr_line
    • invoice_line ↔ contract_clause

B) Purchase Order (PO) - The Rule Container

• Definition: A PO is not just a document; it is a rule container defining what is allowed.
• Capabilities:
  • Structure: Store PO header + line items (structured data).
  • Attachment: Original PO document (PDF/Email).
  • Versioning: Track changes over time (Change Orders).
  • Line-Level Linkage:
    • PO Line → Invoice Line(s)
    • PO Line → GR(s)
  • Tolerance Metadata:
    • Price tolerance
    • Quantity tolerance
    • Over-delivery rules
    • Change order flags

C) Goods Receipt (GR) - The Evidence

• Definition: GR is evidence of fulfillment, not just a quantity field.
• Capabilities:
  • Structure: Store GR records.
  • Attachment: Delivery notes, service confirmations (scans/PDFs/emails).
  • Line-Level Linkage:
    • GR Line → PO Line
    • GR Line → Invoice Line(s)
  • Time Semantics: Distinguish between Receipt Date vs Posting Date.
• Insight: GR proof is often external to ERP. We must store and link these external artifacts.

D) Supplier Contract (V1 Scope)

• Goal: Extract and persist commercially relevant clauses at line-item decision granularity. Do NOT replace CLM or model full legal text.
• Contract Object:
  • contract_id
  • supplier_id
  • contract_type (framework / rate card / subscription)
  • effective_start / effective_end
  • currency
  • status
• Contract Clauses (Structured & Minimal):
  • clause_id, contract_id
  • clause_type: [unit_price, tiered_price, minimum_commitment, billing_frequency, service_scope, termination, indexation]
  • applies_to: [material_id, service_category, PO_line_type]
  • price_logic: (Structured formula/value)
  • tolerance: (Allowable variance)
• In Scope: "Is this invoice allowed under this contract?"
• Out of Scope: Indemnities, liability caps, governing law.

3. The Document Graph (The Moat)

Structure:

• Invoice Line ↔ PO Line
• PO Line ↔ GR Line(s) ↔ Evidence Documents
• Invoice Line ↔ Contract Clause

Enables:

• Approvals (based on rule adherence).
• GR/IR Pre-clearing (automated matching).
• Reconciliation.
• Audit Evidence.

4. System Capabilities (V1)

Storage & Versioning

• Immutable Snapshots: Hashing to prove "this is what was approved".
• Version Links: Clear lineage for Amended POs or Corrected Invoices.

Evidence Bundling

• Requirement: For any financial decision, generate an "Evidence Pack".
• Content: Links + PDFs + Structured Fields.
• State: Frozen at decision time.