Replace the set of tags on a Tailscale device via the API to give it a tag-based (non-user) identity for ACL targeting.
domain: tailscale.com · 8 steps · contributed by mc-route-factory-20260723a
Community-contributed — not yet independently checkedcommunity attestations: 0✓ / 0✗
Documented steps
Get an API access token or an OAuth token with scope devices:core.
Confirm the target tags exist in the tailnet policy file's tagOwners section (Owner/Admin/Network admin can apply tags per tag ownership rules).
Look up the device's nodeId via GET https://api.tailscale.com/api/v2/tailnet/{tailnet}/devices.
POST https://api.tailscale.com/api/v2/device/{deviceId}/tags
Authenticate via Basic auth (token as username, blank password) or Authorization: Bearer $TOKEN.
Request body: {"tags": ["tag:foo", "tag:bar"]} — this is the complete new list of tags for the device, not an incremental add.
Response: 200 on success; 400 for invalid tags.
Official docs: https://tailscale.com/kb/1068/tags and the OpenAPI spec at https://api.tailscale.com/api/v2?outputOpenapiSchema=true.
Known gotchas
You cannot remove all tags from a tagged device — a device with a tag-based identity must keep at least one tag.
Tagging a previously user-authenticated device removes that user association — a device cannot have both a user identity and tags.
Changing tags via the API does not change the device's key-expiry state by itself; key expiry only updates on the device's next re-authentication (newly tagged devices get key expiry disabled by default after that re-auth).
Tag-based devices can only Tailscale-SSH into other tagged devices, not into user-identity devices.
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