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AI can draft your invoice. It cannot decide what to charge.

The Charming Invoices team ·

product
ai

We built this product by reading 768 public complaints about invoicing software, and one of the clearest findings was that the audience we were building for does not want AI features. Not "is cautious about." Does not want.

The dataset contains the phrase "AI slop aesthetic" as a term of art. It contains a long thread about a restaurant's AI-generated logo, with replies like "If it looks AI it's bad. If you literally drew it entirely by hand and it still looks AI, it's still bad," and a designer's test for a logo that is really a test for the whole category: "can you embroider it or put it on an invoice? No? Then it's not a good logo." These are people whose work is the product — writing, photography, design, craft — and generated output reads to them as the cheap imitation of what they do for a living.

So we are not going to pitch you an AI-native invoicing platform. What we have is one narrow, optional drafting feature, and the useful thing we can do here is describe it precisely enough that you can decide it is not for you.

What the feature is

On the invoice form there is a button: Generate with AI. It opens one dialog with one box, labelled "What are you billing for?". You type a sentence — the placeholder in the box is literally "10 hours of design work at $80/hr for Acme Ltd, plus a $150 rush fee" — and it fills in the line items.

That is the whole feature. There is no chat, no assistant panel, no follow-up questions, no AI anywhere else in the product. It exists because typing out the same five line items for the fourth time this month is tedious, and for no other reason.

The five things it is not allowed to do

These are constraints in the code, not promises in the marketing.

1. It cannot save or send anything. The draft lands in the form you were already looking at. The dialog even says so: the line items "land in the form for you to check and edit — nothing is saved or sent." Nothing reaches a client without you reviewing the invoice and pressing send yourself, exactly as if you had typed every line.

2. It leaves a price at zero rather than guessing one. The instruction the model is given is explicit: if a rate or amount is not clearly stated for an item, set the price to 0 rather than guessing — the user will fill it in themselves. A blank you have to notice is a far better failure than a plausible-looking number you do not. Your rate is not something a language model gets to infer.

3. It cannot create a client. If your sentence names a company, that name is used only to select a client you already have. If nothing matches, nothing is selected and the confirmation tells you to pick one. It never adds a client record, and it never invents a name — if your description does not name anyone, it returns nothing rather than filling the field.

4. It cannot touch tax, discounts or totals. It is restricted to the billable work itself. Every total on the invoice is computed by the same arithmetic the rest of the app uses, from the numbers you can see, so there is no path where a draft quietly changes what the invoice adds up to.

5. It cannot silently overwrite your work. A draft is the whole set of line items, so applying one replaces what is in the form. If you have already typed something, you are asked to confirm before anything is lost — and the confirmation says plainly that lines will be replaced rather than added.

Two smaller details in the same spirit. Every successful draft shows the same message: "Check every line and price before saving." And when a draft fails — a bad connection, a response we cannot validate, a request that takes too long — the error does not offer a half-guess, it says: "Could not generate a draft. Try rephrasing, or fill it in yourself."

The actual argument

AI should save you typing. It should not make decisions about your client relationship or your money.

Three decisions this feature never makes: the price, the client, and the send. Those are the three that matter, and they are the three that are structurally out of its reach rather than merely discouraged. Everything else is transcription — turning a sentence you already know into rows in a table, which is the kind of boring work worth automating.

It is also, deliberately, the kind of feature you can ignore completely. Do not press the button and the product behaves exactly as it does for everyone who never presses it. Nothing about the invoice form, the templates or the sending flow depends on it.

What we did not build, on purpose

  • No AI-written chasing emails. One person in our research explained why better than we could, describing other tools' reminder templates as "so stiff and robotic that it feels awkward to send to clients I have a good relationship with." A generated follow-up to someone you know is worse than three words you write yourself.
  • No AI logo or branding generation. See the logo thread above. Your logo is a file you upload.
  • No AI "insights." You can see your own invoices.
  • No sparkle on the homepage. The research says calling ourselves AI-powered would actively cost us trust with the exact people we built this for, and we believe it.

When it earns its place, and when it does not

Worth using: a long multi-item job you would otherwise type out line by line; a messy note you dictated into your phone after a site visit; the fourth near-identical invoice this month where the wording is the same but the quantities are not.

Not worth using: a single flat fee. Typing "Brand identity — primary logo, two lockups, type and colour system" and one number is faster than describing it in a sentence first. And if you bill the same client the same thing every month, recurring invoices or a saved line-item library are the right tools — a draft you review every time is the wrong shape for work that never changes.

It is a paid feature, and here is the honest reason

Every draft is a real call to a model provider that costs us real money per use, and it is the only thing in the product that does. So AI drafting sits on the paid tiers — Individual Lifetime at $29 once, and up — and is not part of the free tier.

Free keeps everything that costs us nothing per use: one business with genuinely unlimited clients and invoices, your logo, all 18 invoice templates and every customization option, public invoice links and PDFs. We would rather gate the one feature with a per-use cost than cap the number of invoices you can send, which is the trade we explain in the real cost of free invoicing apps. The full tier list is on the pricing page.

Where it will let you down

It is a language model. It sometimes splits one thing into two lines, or merges two into one. Ambiguous phrasing produces an ambiguous reading. It has no idea what you normally charge, whether this client gets your rush rate, or that the deposit was already paid.

Which is precisely why it is shaped like this: the output is a starting point in an editable form, every number is yours to set, and nothing happens until you press send. If that sounds like a smaller feature than the word "AI" usually implies, good. That is the version we wanted.