AgentSign

For humans

Easy signing for everything, by people and their AI agents.

Drop a PDF or POST it. Your signer gets a link, and you get back a sealed file with an audit trail. No account to send and none to sign. We shred it after 7 days unless you keep it.

Connect your AI agent →Bring your team →
View as machine

For agents & developers

POST /v1/documents
$ curl -F title='Repair authorization' \
       -F sender_email=you@example.com \
       -F signers='[{"name":"Jane",
         "email":"jane@example.com"}]' \
       -F file=@form.pdf \
       https://agentsign.co/v1/documents
# your agent can sign off too, with its own
# named key. it gets a cryptographic
# receipt, not a pretend signature
$ curl -X POST \
    https://agentsign.co/v1/documents/doc_kx3q9/attest \
    -H 'authorization: Bearer sign_agent_...'
> receipt 4c19…9e2f · recorded 14:02:59 UTC

Signing inside your own product, not ours.

REST + OpenAPIMCP: send · status · attest · verifyself-host: SELF_HOST=1

So what is this?

Accounts are optional

You drop a PDF. Your signer taps a link. An account is never the price of a signature; make one only when you want a place to keep what you've signed. The file comes back sealed, with proof of everything that happened.

SENT

We email your signer a link. They never need an account. Neither did you.

SIGNED

They review the PDF, consent, and sign by hand on any device.

SEALED

You both get the sealed file, the certificate, and the full audit trail. We shred our copy in seven days unless you keep it.

View as machine

Status

GET /v1/documents/{id}
$ curl https://agentsign.co/v1/documents/doc_kx3q9 \
       -H 'authorization: Bearer sign_live_...'
{ "status": "completed", "signers": [ … ], "audit": [ … ] }

> completed 14:09:41 UTC · kept 7 days unless you keep it

What do agents have to do with it?

It speaks agent and developer

Every month, more of your paperwork is handled by something that isn't a person. AgentSign is built for that turn, and the audit trail names everyone who took it.

PEOPLE

Sign by hand, like always. The pen stays yours.

AGENTS

Hold a named key and sign off with a cryptographic receipt, never a faked signature.

DEVELOPERS

Get the whole rail: REST, OpenAPI, MCP tools, and webhooks.

Connect your AI agentMCP tools →
View as machine

Your agent's turn

POST /v1/documents/{id}/attest
# its own named key. its own receipt.
$ curl -X POST \
    https://agentsign.co/v1/documents/doc_kx3q9/attest \
    -H 'authorization: Bearer sign_agent_...'

> receipt 4c19…9e2f · recorded 14:02:59 UTC

Why believe any of it?

The file is the proof.

Every sealed PDF carries its own evidence. Post it back any time; anyone can run the check, no key and no account.

THE SEAL

The file is byte for byte the one that was signed. Any edit breaks it.

THE SIGNATURES

Who signed, when they signed, and the consent they gave.

THE RECEIPTS

Which named agents signed off, and when.

The code is open, so you can run the whole service yourself.

See pricingRead the docs →
View as machine

Verify

POST /v1/verify
$ curl -F file=@sealed.pdf \
       https://agentsign.co/v1/verify
{ "valid": true, "human_signatures": 1, "agent_attestations": 1 }

> anyone can run this. no key.

Always free, open source

Apache-2.0. Run it yourself forever, or use the cloud free tier.

Team plans, no per-seat pricing

Pro is one flat price. Invite your whole team. Seats aren't a thing here.

For humans and agents alike

People sign by hand. Agents sign off with named keys. Your platform integrates over REST, OpenAPI, or MCP.