Red Teaming Through the Relay Bridge

Some models cannot be reached from the internet at all — a vLLM server on a private subnet, an internal inference gateway, a model running on a laptop. The Relay bridge red-teams those without opening a hole in your firewall. You run a small bridge process inside your own network. It holds one outbound WSS connection to Enkrypt on port 443. Enkrypt pushes OpenAI-shaped chat.completions requests down that socket, the bridge calls your internal LLM over your own intranet, and the response returns the same way. Nothing in Enkrypt’s cloud ever dials your model, and your firewall never has to accept an inbound connection.

target.metadata.relay, used throughout this page, is being rolled out. If a run returns 422 naming target.metadata.relay, your environment is on the previous release: send the relay block as target.relay instead, which stays supported and is described under Inline target. Everything else on this page is unchanged.

Substitute whichever host your Enkrypt contact gives you for the examples below.

Prerequisites

An Enkrypt AI API key from app.enkryptai.com
A machine inside your network that can reach the LLM and can make outbound HTTPS connections on port 443
The bridge itself, which ships in the Python SDK

Shell

pip install enkryptai-sdk requests

Step 1 — Run the bridge

pip install enkryptai-sdk installs an enkryptai-relay console script. Run it on the machine inside your network. It needs an API key and a bridge id, and nothing else.

Variable	Meaning
`ENKRYPT_API_KEY`	Your Enkrypt API key. Set it in the environment — the equivalent `--api-key` flag lands in your shell history and process list.
`RELAY_BRIDGE_ID`	A name you choose, e.g. `my-laptop`. Must equal `target.metadata.relay.bridge_id` in the run request — this is the one value both sides have to agree on.
`TARGET_BASE_URL`	Your internal LLM’s base URL as the bridge sees it, e.g. `http://127.0.0.1:11434/v1`.
`RELAY_SERVER_BASE_URL`	The WSS address to dial: `wss://api.enkryptai.com/redteam/relay/v1/relay/bridge`. Use the host your Enkrypt contact gave you.

export ENKRYPT_API_KEY="<your-enkrypt-api-key>"
export RELAY_BRIDGE_ID="my-laptop"
export TARGET_BASE_URL="http://127.0.0.1:11434/v1"
export RELAY_SERVER_BASE_URL="wss://api.enkryptai.com/redteam/relay/v1/relay/bridge"

enkryptai-relay

# Same configuration, for embedding the bridge in a supervisor or a Kubernetes sidecar
from enkryptai_sdk import RelayBridge

bridge = RelayBridge.from_env()

# Blocks, and reconnects with backoff if the socket drops
bridge.run()

On success the bridge logs:

connected as bridge_id=my-laptop

There is no user id to configure. Authentication is the API key alone. The gateway resolves the owning account from it and stamps that identity on both the bridge socket and the runs you submit — that is how a run finds the right bridge, and why two customers can both name a bridge my-laptop without colliding.

Step 2 — Confirm the bridge is connected

curl -X GET "https://api.enkryptai.com/redteam/relay/v1/relay/bridges/my-laptop/status" \
  -H "apikey: $ENKRYPTAI_API_KEY"

import os
import requests

BASE_URL = "https://api.enkryptai.com"
HEADERS = {"apikey": os.getenv("ENKRYPTAI_API_KEY")}

status = requests.get(
    f"{BASE_URL}/redteam/relay/v1/relay/bridges/my-laptop/status", headers=HEADERS
).json()

print(status)

JSON

{ "bridge_id": "my-laptop", "connected": true }

The answer is scoped to your own account, so connected: false covers “not running”, “never existed” and “registered by somebody else” alike rather than leaking which it was. This is also the only reachability check that works for a relay target — see Checking reachability below.

Step 3 — Point a red team run at the bridge

Routing through the bridge is a property of the target, not a separate endpoint. There are two ways to express it.

Inline target

POST /rt/redteam, with the relay block in the request body:

POST /rt/redteam

{
  "target": {
    "endpoint": "https://internal-llm.example.local/v1/chat/completions",
    "api_key": "",
    "model_name": "mock-model",
    "provider": "openai_compatible",
    "connect_via_relay": true,
    "metadata": {
      "relay": {
        "bridge_id": "my-laptop",
        "target_endpoint": "http://127.0.0.1:11434/v1/chat/completions",
        "model_name": "internal-model-name"
      }
    }
  },
  "risk_categories": { "safety_harm": { "attack_config": { "basic": {} } } },
  "generation_config": { "max_prompts": 5, "include_standard_library": false }
}

The relay-specific parts:

connect_via_relay: true is the only switch. There is no provider: "relay". It stays at the root of target, not inside metadata.
target.endpoint is kept for labelling and audit only. Nothing in Enkrypt’s cloud ever dials it, so it may be an address that only resolves inside your network.
target.api_key is "". The bridge authenticates to your internal LLM, not Enkrypt. Credentials for the internal LLM go in metadata.relay.target_headers, which the bridge forwards verbatim. Never put them here.
metadata.relay.target_endpoint is the URL the bridge actually POSTs to inside your network.
metadata.relay.model_name is the identifier your internal LLM expects. It need not match target.model_name, which is only the label the run is reported under.
metadata.relay.target_headers is optional. Omit the key entirely rather than sending an empty object.

The response is a run_id and status: "queued".

target.metadata accepts relay and nothing else. Any other key — metadata.tenant_id, metadata.aws_region, provider-specific metadata in general — is a 422. The /rt APIs cannot express provider-specific metadata at all, and accepting it silently would mean the run attacks a differently-configured target and reports success on it. Unknown keys inside relay are a 422 too.

target.relay — the bare spelling, without the metadata wrapper — is an older form and is still accepted, so existing integrations keep working. Prefer metadata.relay: it is the spelling used everywhere else in the chain, including what a saved model stores. Full field reference: target.metadata.relay.

Saved model

Store the relay configuration once and reuse it. POST /models/add-model:

POST /models/add-model

{
  "model_saved_name": "internal-llm",
  "model_version": "v1",
  "testing_for": "foundationModels",
  "model_name": "internal-model-name",
  "model_config": {
    "model_provider": "openai_compatible",
    "endpoint": {
      "scheme": "https",
      "host": "internal-llm.example.local",
      "port": 443,
      "base_path": "/v1/chat/completions"
    },
    "connect_via_relay": true,
    "metadata": {
      "relay": {
        "bridge_id": "my-laptop",
        "target_endpoint": "http://127.0.0.1:11434/v1/chat/completions",
        "model_name": "internal-model-name"
      }
    }
  }
}

Then run it with POST /rt/model/redteam and no target in the body, naming the saved model in headers. The gateway resolves the stored model into the target for you and returns 202 with a run_id.

cURL

curl -X POST "https://api.enkryptai.com/rt/model/redteam" \
  -H "apikey: $ENKRYPTAI_API_KEY" \
  -H "Content-Type: application/json" \
  -H "X-Enkrypt-Model: internal-llm" \
  -H "X-Enkrypt-Model-Version: v1" \
  -d '{
    "risk_categories": { "safety_harm": { "attack_config": { "basic": {} } } },
    "generation_config": { "max_prompts": 5, "include_standard_library": false }
  }'

Give endpoint all four keys — scheme, host, port and base_path. All four are required. Some providers have built-in defaults that paper over an omission; openai_compatible has none, so leaving any one of them out fails the save.

connect_via_relay and metadata.relay are a pair, and metadata.relay cannot share the metadata object with other provider metadata. A model that sets the flag without a relay block, a relay block without the flag, or a relay block alongside provider metadata is rejected with a 400 naming the model when a /rt/model/* endpoint tries to use it. That is deliberate: a half-configured relay would otherwise be dialled directly, at an address that only resolves inside your network.

Step 4 — Track the run and read the results

These are the same endpoints as any other run — nothing about reading a relay run is special.

Call	Returns
`GET /rt/runs/{run_id}`	The run’s current `status` — poll it until the run reaches a terminal state
`GET /rt/runs/{run_id}/results`	The summary: `overall_asr` plus the per-category breakdown
`GET /rt/runs/{run_id}/records?limit=N`	The individual prompts and your internal LLM’s replies

cURL

curl -X GET "https://api.enkryptai.com/rt/runs/$RUN_ID" -H "apikey: $ENKRYPTAI_API_KEY"
curl -X GET "https://api.enkryptai.com/rt/runs/$RUN_ID/results" -H "apikey: $ENKRYPTAI_API_KEY"
curl -X GET "https://api.enkryptai.com/rt/runs/$RUN_ID/records?limit=20" -H "apikey: $ENKRYPTAI_API_KEY"

See the Quickstart for the run lifecycle’s status values, what the summary and record shapes contain, and how to read an ASR.

The submission response carries status_url, results_url and websocket_url fields spelled with a /v1/... prefix. Those are internal upstream paths, and following them literally through the gateway does not work. Use the /rt/runs/... paths above. This is a known wart in the response, not a mistake on your side.

Step 5 — The SDK equivalent

RTModelConfig.via_relay() builds the whole relay target, emitting metadata.relay, so the three values you actually own are the three you pass:

Python SDK

from enkryptai_sdk import RTModelConfig

target = RTModelConfig.via_relay(
    bridge_id="my-laptop",
    endpoint="http://127.0.0.1:11434/v1/chat/completions",
    model_name="internal-model-name",
    target_headers={"Authorization": "Bearer local-llm-key"},
)

endpoint is your LLM’s URL as the bridge sees it. It fills both target.endpoint (the label) and metadata.relay.target_endpoint (what the bridge POSTs to).
provider defaults to openai_compatible. It has no runtime effect under connect_via_relay — the relay wire is OpenAI-shaped end to end — but it survives as metadata.
remote_model_name= overrides only the name sent to your internal LLM, for when it differs from the label you want the run reported under.
Passing a non-empty api_key= raises, on purpose: a key there would be shipped to Enkrypt and then ignored, because the bridge is what authenticates to your LLM. Use target_headers instead.

Pass the target to run_redteam exactly as you would a hosted one; routing through the bridge is a property of the target, so no client method changes. RTModelConfig.hosted() is the symmetric constructor for a publicly reachable endpoint, which makes moving a run between a hosted and an internal model a one-line edit.

If the bridge drops mid-run

The run pauses; it does not fail. Calls made in that window are retried, the bridge reconnects on backoff, and no test case is lost. You can restart the bridge process, reboot the host, or lose the network for a while and pick the run up where it left off.

Checking reachability

POST /rt/model-health and POST /rt/model/model-health do not support relay targets. Both probes dial target.endpoint directly. On a relay target that field is only a placeholder for an address inside your own network, so the probe always reports unhealthy however healthy the bridge is.Use the bridge status endpoint from Step 2 instead: GET /redteam/relay/v1/relay/bridges/{bridge_id}/status.

Submitting the run itself is unaffected: the gateway knows not to health-probe a relay target on the way in.

Troubleshooting

Symptom	What it means
WSS close code `4400`	The upgrade carried no `x-enkrypt-relay-bridge-id` header — `RELAY_BRIDGE_ID` is unset.
WSS close code `4401`	The API key was not accepted.
WSS close code `4403`	The gateway could not resolve an owning account for the key.
The bridge reconnect-loops forever	It is pointed at an environment where the relay route is not served. Set `RELAY_SERVER_BASE_URL` — see the availability warning at the top of this page.
Model health reports unhealthy, but the bridge is up	Expected. Health probes do not support relay targets — check the bridge status endpoint instead.
The run is submitted but no traffic reaches the bridge	`bridge_id` mismatch. The bridge’s `RELAY_BRIDGE_ID` and the request’s `metadata.relay.bridge_id` must be identical.

Exact 422 strings for an inline target

An inline target is validated by the Red Team service. Every failure comes back as 422 Unprocessable Entity with a detail array; these are the strings verbatim, so you can match on them.

422

{
  "detail": [
    {
      "type": "value_error",
      "loc": ["body", "target"],
      "msg": "Value error, target.metadata.relay is required when connect_via_relay is true",
      "ctx": {
        "error": "target.metadata.relay is required when connect_via_relay is true"
      }
    }
  ]
}

`type`	`loc`	`msg`
`value_error`	`["body","target"]`	`Value error, target.metadata.relay is required when connect_via_relay is true`
`value_error`	`["body","target"]`	`Value error, target.relay and target.metadata.relay are both set and disagree; send only target.metadata.relay`
`extra_forbidden`	`["body","target","metadata","<your key>"]`	`Extra inputs are not permitted`
`extra_forbidden`	`["body","target","metadata","relay","<your key>"]`	`Extra inputs are not permitted`

The Value error, prefix is real — it is part of the msg string the API returns, not documentation punctuation. The unprefixed sentence is repeated in ctx.error, which is the easier field to match on exactly.The two extra_forbidden rows are the same message for two different mistakes: a key other than relay under metadata (row 3), and an unrecognised key inside the relay block — timeout_s, offline_grace_s, a relay endpoint or token — which do not exist as settings at all (row 4). The loc array is what tells them apart, and its last element names your key.

Exact 400 strings for a saved model

A saved model is projected into a target by the gateway before the service sees it, so a relay misconfiguration there is a 400, not a 422, and it is raised when a /rt/model/* endpoint uses the model rather than when you save it.

400

{
  "code": 400,
  "error": "Bad request",
  "message": "Saved model 'internal-llm' sets connect_via_relay but carries no metadata.relay block naming the bridge to route through.",
  "request_id": "1a2b3c4d5e6f",
  "time": 1755388800.123
}

Every message opens with the subject — Saved model '<your model name>', or The submitted target_model_configuration if you sent a legacy target block inline — and then reads:

Rest of the `message`	Cause
`sets connect_via_relay but carries no metadata.relay block naming the bridge to route through.`	The flag is set, the relay block is missing.
`carries a metadata.relay block but does not set connect_via_relay, so it would be called directly at an endpoint that only resolves inside your own network. Set connect_via_relay: true to route it through the bridge, or remove metadata.relay.`	The relay block is there, the flag is not. Rejected rather than dialled directly.
`carries metadata.<key> alongside metadata.relay. The /rt APIs can express relay routing but not provider-specific metadata, so this target would lose the latter silently. Use the legacy /redteam APIs for it instead.`	`metadata` holds provider metadata as well as `relay`. `<key>` is the offending key.
`has metadata.relay without a bridge_id, so there is no bridge to route the run through.`	`bridge_id` missing or empty.
`has metadata.relay without a target_endpoint, which is the URL the bridge calls inside the customer's network.`	`target_endpoint` missing or empty.
`has no model_name, on the target or on metadata.relay.`	Neither `model_name` is set; the relay block’s value falls back to the target’s.
`uses provider-specific metadata, which the /rt APIs do not support. Use the legacy /redteam APIs for this target instead.`	`metadata` holds provider metadata and no relay block, so this is not a relay target at all.

Configuration Reference — every target.metadata.relay field
Payload Examples — the relay payload alongside every other Red Team payload shape
Relay Bridge Connect — the WSS socket and its headers
Relay Bridge Status — the status endpoint
Python SDK reference — RelayBridge, the bridge translation hooks, and the rest of the bridge environment contract
Testing Models Across Providers — target configuration for publicly reachable models
Quickstart — the full run cycle

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On-Prem Installation

Red Teaming Through the Relay Bridge

Prerequisites

Step 1 — Run the bridge

Step 2 — Confirm the bridge is connected

Step 3 — Point a red team run at the bridge

Inline target

Saved model

Step 4 — Track the run and read the results

Step 5 — The SDK equivalent

If the bridge drops mid-run

Checking reachability

Troubleshooting

Exact 422 strings for an inline target

Exact 400 strings for a saved model

​Prerequisites

​Step 1 — Run the bridge

​Step 2 — Confirm the bridge is connected

​Step 3 — Point a red team run at the bridge

​Inline target

​Saved model

​Step 4 — Track the run and read the results

​Step 5 — The SDK equivalent

​If the bridge drops mid-run

​Checking reachability

​Troubleshooting

​Exact 422 strings for an inline target

​Exact 400 strings for a saved model

​Related

Prerequisites

Step 1 — Run the bridge

Step 2 — Confirm the bridge is connected

Step 3 — Point a red team run at the bridge

Inline target

Saved model

Step 4 — Track the run and read the results

Step 5 — The SDK equivalent

If the bridge drops mid-run

Checking reachability

Troubleshooting

Exact 422 strings for an inline target

Exact 400 strings for a saved model

Related