Home/Smart Locks/Capabilities/Plastic Card Assignment

SMART LOCK CAPABILITIES

Smart Locks That Support Plastic Card Assignment

Seam supports assigned plastic cards on 54 smart lock models from 1 manufacturer, including Salto. The card is already on file in the access system. Seam attaches the credential to it by card number, with nothing to write at the desk.

Ælement Fusion - ANSI
Salto
Models
54
Brands
1
Systems
1

Live & beta integrations · Device database coverage

Every model, and the systems that cover it

54 models are live or in beta today. Status is per system, so one lock can be Live through one system and unavailable through another. Open a model to see which system covers it.
Systems that issue assigned plastic cards · 1 system
  • Salto KSLive

54 compatible models · showing 8

Browse all 54 model links
Browse all 54 models by brand, connectivity and capability
On this page
Quickstart

Assign a key card in 60 seconds

One Access Grant creates the credential. The last step is a call: pass the card number of a card the system already knows, and Seam attaches the credential to it.

1// Set SEAM_API_KEY on your server.
2import { Seam } from "seam"
3
4const seam = new Seam()
5
6const startsAt = new Date()
7const endsAt = new Date(startsAt.getTime() + 3 * 24 * 60 * 60 * 1000)
8// Replace with your own connected device or entrance ID.
9const grant = await seam.accessGrants.create({
10  user_identity: { full_name: "Jane Doe", email_address: "jane@example.com" },
11  acs_entrance_ids: ["f74e4879-5991-4e2f-a368-888983dcfbfc"],
12  requested_access_methods: [{ mode: "card" }],
13  starts_at: startsAt.toISOString(),
14  ends_at: endsAt.toISOString(),
15})
16console.log(grant.access_grant_id) // Save this ID; retrieve access methods and check is_issued before delivery.
Fastest path

Build it with your AI agent

Install the Seam plugin and your coding agent picks up three integration skills: Reservation Automations, Access Grants and Access Codes. It then writes the calls the way we would. Paste the prompt below and let it build.

1. Install the plugin

/plugin marketplace add seamapi/seam-plugin
/plugin install seam@seamapi

The Claude Code install also adds our documentation MCP server, so the agent can look up endpoints and device capabilities while it works. Cursor, Codex and other agents get the skills through npx skills add and can add the MCP server there separately.

2. Paste this prompt

Prompt
Using the Seam Access Grants skill, walk me through assigning a plastic key card. In a sandbox workspace: create a user identity for a member, create an access grant on an entrance with requested_access_methods [{ mode: "card" }] for a one-month window, list the access methods and show me is_assignment_required, then assign a registered card with /access_methods/assign_card and its card_number. Point out where is_issued flips from false to true.
Walkthrough

How it works

  1. Connect the lock and confirm support

    Your user links their lock or access system account through Seam Connect Webview. Seam returns the doors behind it as devices and entrances. There is no device flag for assigned plastic cards: Seam publishes eight boolean capability flags and this is not one of them. Check the device's capabilities_supported array, or ask for { mode: "card" } in requested_access_methods and handle what Seam reports back.

  2. Create an Access Grant

    Name the person, the doors and the window, then ask for a key card in requested_access_methods. Seam works out how to satisfy that on the specific hardware, so the call is the same for a battery deadbolt and a wired reader. Swap acs_entrance_ids for space_ids to cover a group of doors, or device_ids when the door is a standalone lock. The credential's schedule ends at ends_at. Deleting the grant requests removal of its credentials from the connected device or access system.

    1// Set SEAM_API_KEY on your server.
    2import { Seam } from "seam"
    3
    4const seam = new Seam()
    5
    6const startsAt = new Date()
    7const endsAt = new Date(startsAt.getTime() + 3 * 24 * 60 * 60 * 1000)
    8// Replace with your own connected device or entrance ID.
    9const grant = await seam.accessGrants.create({
    10  user_identity: { full_name: "Jane Doe", email_address: "jane@example.com" },
    11  acs_entrance_ids: ["f74e4879-5991-4e2f-a368-888983dcfbfc"],
    12  requested_access_methods: [{ mode: "card" }],
    13  starts_at: startsAt.toISOString(),
    14  ends_at: endsAt.toISOString(),
    15})
    16console.log(grant.access_grant_id) // Save this ID; retrieve access methods and check is_issued before delivery.
  3. Assign the registered card

    List the access methods and read is_assignment_required. Call /access_methods/assign_card with the access method and the card_number printed on, or stored for, the card. is_issued flips to true once the system accepts the assignment, and the card opens the doors on the grant from starts_at.

    1// Set SEAM_API_KEY on your server.
    2import { Seam } from "seam"
    3
    4const seam = new Seam()
    5
    6// Export SEAM_ACCESS_GRANT_ID using the grant created above.
    7const grantId = process.env.SEAM_ACCESS_GRANT_ID
    8if (!grantId) throw new Error("Set SEAM_ACCESS_GRANT_ID")
    9const methods = await seam.accessMethods.list({ access_grant_id: grantId })
    10// Pass the access_method_id and the card_number to /access_methods/assign_card; is_issued becomes true after assignment.
    11for (const method of methods) {
    12  if (method.mode === "card") {
    13    console.log(method.access_method_id)
    14  }
    15}
FAQ

Frequently asked questions

Which smart locks support assigned plastic cards?

Seam supports assigned plastic cards on 54 smart lock models from 1 manufacturer, including Salto. The table on this page comes from Seam's device database, and each model links to its own page with the per-system status and any hardware requirements.

How do I check whether a system can assign a card for a door?

Not with a device flag. can_assign_plastic_cards is a device database capability, not one of the eight booleans on the API's device object. Read capabilities_supported, or request { mode: "card" } on the Access Grant and read is_assignment_required on the access method.

Do I need a card encoder?

No. Assignment attaches the credential to a card the access system has already registered. Systems that write blank cards need an encoder; that is the plastic card encoding page.

Where does the card number come from?

From the access system. Cards are registered there first, usually by scanning them in the system's own software, and the number Seam expects is the one the system reports for the card.

Can the same card open several doors?

Yes. Put every entrance on the Access Grant, or pass a space that covers them, and the card is assigned for all of them at once. Adding a door later updates the credential.

What happens to a card when a stay or membership ends?

The credential expires with the grant, so the card stops opening doors at ends_at whether or not it comes back to the desk. Revoking early is a deletion, not a trip to the lock.

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