Check the License.
Free to download isn't free to use. Before a tool, a model or a song goes into your work, find out what you're allowed to do with it.
“It's online, and it's old. It must be free.”
Which version is this, what does its license say, and does that cover what I'm about to do with it?
“Yes, with one catch.”
My studio is making short illustrated films of great stories, told by a narrator. For now we only use stories that are in the public domain: so old that nobody owns them anymore. One Thursday morning I was picking the first three, and I asked about one of my favorites.
First, the plain truth: I'm not a lawyer, and nothing on this page is legal advice. It's how we keep from tripping over the basics, and how we know when to call someone who is.
so set us up with 3 public domain stories, that are great.. can we use Beowolf? That's one of my favorite stories.. but anyway, we need 3 short stories, […]
Yes, we can use Beowulf, with one catch. The poem itself is over a thousand years old, but each translation has its own copyright. […]
In the part I trimmed, it named a famous modern translation that's still protected, and a translation from 1910 that's public domain and free to read online. That's the one we're using.
I'd have gotten that wrong. In my head, Beowulf is a thousand years old, so it's free. The story is. But nobody reads it in Old English. You read somebody's translation, and that translator's work can be owned for a long time. Same with a classical recording, a photo of an old painting, or a new edition of an old book.
One more wrinkle: the same work can be free in one country and protected in another, so where you publish matters too. Ask your agent about each country you're publishing in.
Allowed for what, exactly?
A license isn't a yes or a no. It's a list of what you may do. The question is always whether it covers what you are about to do: use it yourself, use it inside your business, show it to the public, or sell it. Two catches from the same week show the difference.
[…] The music service we've been using allows our own internal use, but it doesn't clearly let us release the music publicly. Our proofs are internal, so they're fine. […]
[…] test an open music model that runs on our own laptop at no cost, and only one whose licence allows commercial use. […]
Nothing with generated music goes public until one of those is cleared.
Our AI composer read the music service's terms while it was setting up. They allowed personal or internal business use. That covers drafts we watch in the studio. It doesn't clearly cover a film anyone can see. So drafts carried on, and the public version waits.
The second catch was a tool, not a song. We use a face-checking model to make sure a character looks like the same person from picture to picture. The code was free to use, but the trained model behind it was licensed for non-commercial research only, and our films are a business. That afternoon we moved to tools under Apache 2.0, a license that allows commercial use. Notice we didn't panic, either:
“Pictures already approved keep their old scores on record, and nothing gets re-run.”
Fix it going forward, write down what happened, and keep working. That's the job.
A few words worth knowing.
You don't need to read every license yourself. Your agent can, and it's good at it. But a handful of labels come up again and again, and it helps to know them on sight:
Creative Commons: CC0, CC BY, and the little “NC.”
CC0 means no strings. CC BY means you may use it, but you must credit whoever made it, so keep a credits list. NC means non-commercial. For one of my games I told my agents to use only CC0 or CC BY sound effects, never NC, because the game may be sold someday.
Code: MIT and Apache 2.0.
These are permissive: you can generally build on them, even in paid work, as long as you keep their notices. Some other code licenses come with conditions when you share what you built. That's a question for your agent to spell out.
Red-flag phrases.
“Personal use.” “Internal use.” “Research only.” “Evaluation.” And the biggest one of all: no license at all. Generally, no license doesn't mean free. It means nobody gave you permission.
AI models have two licenses.
One for the code, one for the trained model, and they can differ, like the face checker above. Have your agent check both.
When my agent wrote up the music terms, it put this line right at the top of its notes: “These are the terms as published, not legal advice.” That's the right spirit. Find the real words, quote them, link them, and be honest about what they don't settle.
Unclear means stop, and a human decides.
The day before, an agent working on narrator voices found a voice model it liked. To download it, you had to click “I accept” on its terms. It didn't click. It wrote:
“The top model's weights also sit behind accept-terms, which I can't accept without explicit permission. So I can't pick this route myself; it goes back to the maestro.”
The maestro is my lead agent. The question came to me with the facts beside it, and I ruled in three words: “Yes, internal only”. Agreeing to terms is signing something. That's a human's job.
And when the question is really legal, it isn't even mine. I'm the technical guy. I told my agents so: “I'm strict, strictly technical from now on anything legal goes to our team”. If real money, a client or a public release rides on it, ask someone who does this for a living.
Fifteen minutes, one project.
Pick something you're making or about to publish. Then:
- List what you didn't make.
Photos, fonts, music, sound effects, quotes, code, AI tools and models. If you didn't create it from scratch, it goes on the list.
- Have your agent check each one.
Paste this, with your list:
Here's everything in my project that I didn't make myself. For each one, find its license or terms and tell me: who made it; which version I'm using; what the license allows for my use (personal, inside my business, public, or something I sell); whether I have to credit anyone, and how; and anything unclear. Quote the exact line you're relying on and link to it. Say plainly where you're unsure. Don't accept any terms or click "agree" for me. - Read the flags it raises.
Anything marked NC, personal, internal, research or evaluation only, or with no license at all, doesn't go into public or paid work until it's cleared or replaced.
- Keep a credits file.
One note listing every CC BY item and the credit it asks for. Have your agent update it whenever something new comes in.
- Know your stop line.
Unclear terms, an “I agree” button, a public launch, a client's work, or something you'll sell: that's where a human decides. If it matters, that human is a lawyer.
Before anything you didn't make goes into your work, have your agent find its license, quote the exact words and match them to what you're doing, and when it isn't clear, stop and let a human decide.
No Unhappy Agents
A frustrated agent does worse work. A warm start and a way out of the loop turn it around.
Every exchange on this page really happened and is quoted exactly, slips included; […] marks where I trimmed. My agents spell it “licence” sometimes; I left that as they wrote it. This lesson is not legal advice. Times are Eastern. My agent here is Claude, made by Anthropic.