# Write data on the BSV chain with consent: every rule
Every do and don't the guide states on the pages behind this skill. The costly ones come first; the full list follows, grouped by page. Quote them; do not paraphrase them.
10 rules: 1 that can cost money, 5 that can cost trust, 4 standard.
## Start here
- **DON'T** _(Costs money)_ Write anything identifying a person without an explicit, specific consent for that write. "Agreed to the terms" is not consent to publish somebody's name forever.
- **DO** _(Costs trust)_ Say "permanent and public" in the consent step, in those words, before anything is written.
- **DO** _(Costs trust)_ Show exactly what will be written. If it is a hash, say that the document stays on your server and only a fingerprint goes out.
- **DON'T** _(Costs trust)_ Offer a delete button for on-chain data. You can stop displaying it. That is not the same thing and the difference is the whole point.
- **DO** _(Costs trust)_ Default to the hash. Publishing is the irreversible option and should be the deliberate one.
- **DO** _(Costs trust)_ Make sure the data can still be verified without your overlay. The point of putting it on chain was independence from you.
## Every rule, by page
### Storing data on chain
https://www.bitcoinsv.design/guide/patterns/storing-data-on-chain/
- **DO** _(Costs trust)_ Say "permanent and public" in the consent step, in those words, before anything is written.
- **DO** _(Costs trust)_ Show exactly what will be written. If it is a hash, say that the document stays on your server and only a fingerprint goes out.
- **DON'T** _(Costs money)_ Write anything identifying a person without an explicit, specific consent for that write. "Agreed to the terms" is not consent to publish somebody's name forever.
- **DON'T** _(Costs trust)_ Offer a delete button for on-chain data. You can stop displaying it. That is not the same thing and the difference is the whole point.
- **DO** _(Costs trust)_ Default to the hash. Publishing is the irreversible option and should be the deliberate one.
- **DO** Treat the overlay as a dependency the user should know exists, the way you would treat any other service. See Interoperability.
- **DO** _(Costs trust)_ Make sure the data can still be verified without your overlay. The point of putting it on chain was independence from you.
- **DO** Show progress honestly for anything large, and say what happens if it stops halfway. A partially written file is a real state, not a theoretical one.
- **DON'T** Put a large file on chain because you can. Cost is not the constraint; permanence is, and so is the user's understanding of it.
- **DO** Say "anchored in block 951,204" alongside the human date. The block is the fact; the date is the convenience.