Prooflane — Audit Folio

Invoice and contract files

FOR ACCOUNTS PAYABLE REVIEWERS

Know which price difference to investigate first.

Connect invoices to dated contract prices, test what could change your priority, and keep a review another person can reproduce.

Fictional sources · fixed rules · no AI cost
7 included invoices, one recorded exclusion.

Source files and case name Inspect or change inputs

Case name

CSV field guide and starter files

Use the exact columns and order shown below. Vendor and item keys match exactly after trimming. Dates use YYYY-MM-DD; both contract dates are inclusive. Quantities are positive whole numbers; prices are nonnegative USD with at most two decimals.

Invoice register

invoice_id: Your reference; repeated IDs are kept as separate rows.
vendor + item_id: The keys linking this invoice to a contract.
invoice_date: Date used to choose the effective contract.
quantity + unit_price: Billed quantity and price per unit.
notes: May be empty.

Contract register

contract_id: A distinct ID for each version.
vendor + item_id: Must match the corresponding invoice keys.
valid_from + valid_to: Inclusive effective period; start is no later than end.
contract_price: Supplied unit price, not independently authenticated.

Invoice register

Invoices

UTF-8 CSV · up to 128 KiB · 500 rows

Choose invoice CSV

Paste or inspect CSV

invoice_id,vendor,item_id,invoice_date,quantity,unit_price,notes

Contract register

Contracts

USD prices · inclusive effective dates

Choose contract CSV

Paste or inspect CSV

contract_id,vendor,item_id,valid_from,valid_to,contract_price

Source decisions

Vendor and item must match exactly. The invoice date must fall within the contract period.

Invoice and contract matching decisions
Invoice	Invoice date	Contract	State

1 Import two CSVsKeep the original sources.2 Resolve the matchesChoose overlaps, explain exclusions.3 Freeze a baselineExplore assumptions with receipts.

Invoice variances

Invoice register

Positive differences against supplied contract prices. USD.

Included source rows and their positive price variance
Invoice and vendor	Source link	Variance

Supplied-data review signals. A positive difference does not establish contractual liability or recovered savings.

Review assumptions

SUPPLIED ORIGINAL—Create a baseline to compare.

Sensitivity to one assumption

Case positive variance at each declared endpoint. Others fixed.

View exact values

Scroll sideways to read every column.

One-at-a-time endpoint calculations
Target	Low → total	High → total	Span

Trusted estimate · not an executed alternative. Endpoint effects cannot be added to calculate joint changes.

DECLARE A RANGE

Make uncertainty explicit.

Assumption target

Low value

High value

Include the original value. A shared contract moves every bound invoice together.

Evidence to check next

How much range disappears if this input is learned exactly.

PRIORITY UNDER DECLARED RANGES

Contract break-even values

Named alternatives

Each starts from the original baseline and recalculates every change jointly.

Scroll sideways to read every column.

Baseline and completed named alternatives
Alternative and changes	Positive variance	Change	Flagged	State

Ranges are user-declared assumptions, not probabilities. Alternative results are hypothetical; source evidence stays unchanged.

A claim with a paper trail.

Follow a source record

Follow the source → calculation → receipt. The checks establish consistency and arithmetic; they do not authenticate a supplier or contract.

PORTABLE CASE EVIDENCE

Carry the record forward.

Download review CSV ↓Download review brief ↓Download case packet ↓

Includes source data. Keep it where that data may be shared.

Hashes detect changes. They do not authenticate the issuer, the runtime, or the supplied contract.

Baseline execution, code and receipt

Check sandbox containment

Run fixed probes in a fresh container using the same runtime as a review.

Verify a case packet

Uploads the packet and its included source data to this server for verification. No code is executed. Use the CLI for offline verification.

Read-only verification

Packet verification checks arithmetic and content integrity. It does not prove contract truth, issuer identity or execution environment.

Review archive

Start an invoice review

Invoice and contract files

Know which price difference to investigate first.

Invoice register

Contract register

Source files need attention

Invoices

Contracts

Source decisions

Invoice variances

Invoice register

Review assumptions

When would the review priority change?

Sensitivity to one assumption

Make uncertainty explicit.

Evidence to check next

Named alternatives

A claim with a paper trail.

Carry the record forward.

Check sandbox containment

Verify a case packet

Single-file review

Your review

Review workspace

A finding is the start.
Follow it through.

Following the numbers.

What if one input changed?

Where the variance sits

Follow each finding

The work behind the answer

Trust is a check.
Not a badge.

Containment check

Invoice finding

Invoice and contract files

Know which price difference to investigate first.

Invoice register

Contract register

Source files need attention

Invoices

Contracts

Source decisions

Invoice variances

Invoice register

Review assumptions

When would the review priority change?

Sensitivity to one assumption

Make uncertainty explicit.

Evidence to check next

Named alternatives

A claim with a paper trail.

Carry the record forward.

Check sandbox containment

Verify a case packet

Single-file review

Your review

Review workspace

A finding is the start.Follow it through.

Following the numbers.

What if one input changed?

Where the variance sits

Follow each finding

The work behind the answer

Trust is a check.Not a badge.

Containment check

A finding is the start.
Follow it through.

Trust is a check.
Not a badge.