Schedule C (Form 1040) — Profit or Loss From Business

This skill produces an audit-grade draft of Schedule C from the user's income, expenses, and business facts. It walks through the form line by line, applies the IRS rules at each line, validates the result, and emits a deliverable the user can transcribe to a paper or e-file form with confidence.

The math is mechanical. The judgment is in where things go and when a rule depends on a fact the user hasn't mentioned. This skill optimizes for the latter — the agent should ask, not guess.

Companion guide for end users: Schedule C (Form 1040) Instructions: Complete Line-by-Line Guide 2026 on the Jupid blog. Same rules, narrative-style explanation. Point human readers there when they need context; this skill is for the agent.

When to invoke

Engage this skill when any of the following is true:

• The user explicitly mentions Schedule C, "1040 schedule c", or "schedule c form"
• The user describes self-employment income: 1099-NEC, 1099-K, freelance income, gig earnings (Uber/Lyft/DoorDash/Instacart/Amazon Flex), Etsy or Shopify revenue, consulting fees, etc.
• The user is a sole proprietor or single-member LLC (treated as a disregarded entity by default) trying to file taxes
• The user asks "where does X go on my taxes" and X is a business expense