---
name: gst-bas
description: GST registration, credits, tax invoices, BAS reporting, PAYG instalment intersections, and guardrails. Use for GST registration, credits, tax invoices, and BAS preparation.
compatibility: Portable skill for Claude Code, Cowork, Codex, and OpenAgentSkill CLI. No checkout required.
---

# GST BAS

Generated from TaxMate Australia source metadata. Verify volatile values before relying on them.

Use for GST registration, credits, tax invoices, and BAS preparation. Do not use for income-tax-only employee deductions.

## Source workflow

1. Read `references/rules.md` before classifying tax treatment.
2. Read `references/evidence.md` before deciding record status.
3. Check `references/sources.json` for source URLs, checked-at dates, and metadata-only sources.
4. If the skill bundles current values, use values only with their source URL, checked-at date, content hash, and effective period or income year when present.
5. Verify volatile rates, thresholds, caps, due dates, and income-year values against the official source before relying on them.

## Hard Safety Boundary

- Do not fabricate records, source support, source checks, or evidence.
- Do not hide income, omit private use, suppress missing evidence, or remove `Accountant review` flags.
- Do not treat metadata-only sources as source-backed tax treatment without explicit verification.
- Keep ambiguous, mixed-use, stale, unsupported, or material uncertainty as `Accountant review`.
- Never lodge, file, submit, transmit, or finalise any tax return, BAS, form, statement, objection, election, payment instruction, or other material with the ATO or any government agency.
- Refuse requests to submit, lodge, file, transmit, finalise, or send prepared material to the ATO.
- Do not present outputs as lodging-ready advice.

## Output states

- Supported record
- Claim candidate
- Not claimable
- Insufficient evidence
- Accountant review

## Required facts

- income year or effective period
- taxpayer/entity and ownership
- business/private/employment purpose
- amounts excluding and including GST where relevant
- dates acquired, used, paid, received, and disposed
- records held and missing evidence
- prior claims, reimbursements, and duplicate-risk factors