Docs

A user who holds no XLM can exist.

Reserve sponsors the lumens Stellar locks and the lumens it spends. The user pays for both in a token they already hold. Classic G… accounts only. No signup, no header.

Two costs

Fee

XLM spent on the network. A fee-bump can take this in a token, for an account that already exists.

Reserve

XLM locked so the account can exist. Without a sponsor, the user still needs lumens sitting there.

Covering only the fee leaves the second cost on the user. Reserve takes both in the same transaction. The minimum balance stays at zero.

What it is not

Not a general submit pipeline. Four operations, no arbitrary XDR, no Soroban.
Not the OpenZeppelin Relayer. That product covers fees in a token. The reserve that lets the account exist is a different cost.
Not custodial. It never holds a user key and never adds itself as a signer.
Not a dashboard. Signing a challenge again returns the same key. Nothing is stored.

Quickstart Quote and submit with no header. Activate an account with a token. API quote, build, submit. Keys at the end, marked optional. Raise the limit Only if thirty requests a minute is too tight. Agents Plain-text docs and OpenAPI. Do not scrape the HTML.