Create signing envelope
create_signing_envelopeCreate a FreeSign envelope from a PDF SHA-256 hash. Do not send PDF bytes. The created envelope is NOT yet session-bound — the browser that opens the returned signing_url generates an ECDSA P-256 keypair locally and POSTs the public JWK to /api/envelopes/{id}/session-bind before any protected request will succeed. AI agents calling this tool just hand the signing_url to a human, who continues in a browser.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| document_sha256 | Yes | SHA-256 of the original PDF bytes, computed locally by the user or agent. |
Output Schema
| Name | Required | Description | Default |
|---|---|---|---|
| expires_at | Yes | ||
| envelope_id | Yes | ||
| signing_url | Yes | ||
| session_binding_required | No | True when the envelope still needs the browser to call /api/envelopes/{id}/session-bind. Always true for MCP-created envelopes. |