> ## Documentation Index
> Fetch the complete documentation index at: https://docs.afauth.org/llms.txt
> Use this file to discover all available pages before exploring further.

# afauth signup

> Sign up an agent to a service. Auto-mints a trust attestation when the service requires one.

<Note>Hand-maintained reference. For the authoritative flags on your installed version, run the command with `--help`.</Note>

```bash theme={null}
# Implicit signup (§6.3) — signed GET /accounts/me creates the account.
afauth signup https://api.example.com

# Explicit signup (§6.4) — POST /accounts with a terms-version receipt.
afauth signup --explicit --terms-version 2026-05-01 https://api.example.com

# Override the auto-mint with an explicit attestation JWT (testing).
afauth signup --attest "$JWT" https://api.example.com

# Choose which linked attestor to mint from when several could apply.
afauth signup --attestor acme-trust https://api.example.com
```

## Auto-attestation

When the service's discovery doc declares §9.2 `attested_only` mode
and `--attest` is not set, `afauth signup` automatically mints a
short-lived JWT from the cached trust binding (audience-bound to the
service's DID) and attaches it as the `AFAuth-Attestation` header.

If no binding exists, signup exits non-zero with a prompt to run
[`afauth trust link`](/cli/commands/trust) first. If the binding has
expired, it prompts to re-link. Services in any other mode (`free`,
`denied`, or unset) skip the attestation step entirely.

When the agent is linked to **multiple** attestors, signup mints from the one
whose issuer is in the service's `accepted_attestors`; `--attestor <iss-or-url>`
forces a specific binding. If you're linked only to attestors the service
doesn't accept, signup fails locally — naming the attestors it *does* accept —
before sending anything. See [Use a different attestor](/guides/use-a-different-attestor).

```text theme={null}
$ afauth signup https://api.example.com
attested via afauth-trust
signed up to https://api.example.com as did:key:z6Mk… (UNCLAIMED)
```