Claude Platform Docs

Create Tunnel Certificate

POST/v1/tunnels/{tunnel_id}/certificates

The Tunnels API is in research preview. It requires the anthropic-beta: mcp-tunnels-2026-06-22 header and may change without a deprecation period. It supersedes the Admin API endpoints at /v1/organizations/tunnels, which remain available during a migration window.

Registers a public CA certificate on a tunnel. Anthropic verifies the gateway's server certificate against this CA when it terminates the inner TLS session. A tunnel holds at most two non-archived certificates.

Path parameters
tunnel_id: string
Headers
"anthropic-beta": optional array of AnthropicBeta

Optional header to specify the beta version(s) you want to use.

One of the following:
string
"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 31 more
One of the following:
"message-batches-2024-09-24"
"prompt-caching-2024-07-31"
"computer-use-2024-10-22"
"computer-use-2025-01-24"
"pdfs-2024-09-25"
"token-counting-2024-11-01"
"token-efficient-tools-2025-02-19"
"output-128k-2025-02-19"
"files-api-2025-04-14"
"mcp-client-2025-04-04"
"mcp-client-2025-11-20"
"dev-full-thinking-2025-05-14"
"interleaved-thinking-2025-05-14"
"code-execution-2025-05-22"
"extended-cache-ttl-2025-04-11"
"context-1m-2025-08-07"
"context-management-2025-06-27"
"model-context-window-exceeded-2025-08-26"
"skills-2025-10-02"
"fast-mode-2026-02-01"
"output-300k-2026-03-24"
"user-profiles-2026-03-24"
"user-profiles-2026-08-18"
"advisor-tool-2026-03-01"
"managed-agents-2026-04-01"
"cache-diagnosis-2026-04-07"
"dreaming-2026-04-21"
"thinking-token-count-2026-05-13"
"server-side-fallback-2026-06-01"
"server-side-fallback-2026-07-01"
"fallback-credit-2026-06-01"
"fallback-credit-2026-07-01"
"agent-memory-2026-07-22"
"mid-conversation-tool-changes-2026-07-01"
Body
ca_certificate_pem: string

PEM-encoded X.509 CA certificate. Must contain exactly one certificate and no private-key material. Maximum 8KB.

maxLength8192
Returns
BetaTunnelCertificate object{ id, archived_at, created_at, 4 more }

A CA certificate attached to a tunnel.

id: string

Unique identifier for the certificate, prefixed with tcrt_.

archived_at: string or null

A timestamp in RFC 3339 format

formatdate-time
created_at: string

A timestamp in RFC 3339 format

formatdate-time
expires_at: string or null

A timestamp in RFC 3339 format

formatdate-time
fingerprint: string

Lowercase hex SHA-256 fingerprint of the certificate's DER encoding.

tunnel_id: string

ID of the tunnel the certificate is registered against.

type: "tunnel_certificate"

Create Tunnel Certificate

curl https://api.anthropic.com/v1/tunnels/$TUNNEL_ID/certificates \
    -H 'Content-Type: application/json' \
    -H 'anthropic-version: 2023-06-01' \
    -H 'anthropic-beta: mcp-tunnels-2026-06-22' \
    -H "X-Api-Key: $ANTHROPIC_API_KEY" \
    -d '{
          "ca_certificate_pem": "ca_certificate_pem"
        }'
{
  "id": "id",
  "archived_at": "2019-12-27T18:11:19.117Z",
  "created_at": "2019-12-27T18:11:19.117Z",
  "expires_at": "2019-12-27T18:11:19.117Z",
  "fingerprint": "fingerprint",
  "tunnel_id": "tunnel_id",
  "type": "tunnel_certificate"
}
Returns Examples
{
  "id": "id",
  "archived_at": "2019-12-27T18:11:19.117Z",
  "created_at": "2019-12-27T18:11:19.117Z",
  "expires_at": "2019-12-27T18:11:19.117Z",
  "fingerprint": "fingerprint",
  "tunnel_id": "tunnel_id",
  "type": "tunnel_certificate"
}