Get an Order

Returns one of the caller’s orders by its identifier.

GET/orders/{order_id}

Authorization

UDX-Access-KeyAPI key · headerrequired

Opaque API key ID.

UDX-Access-TimestampAPI key · headerrequired

Unix time in milliseconds, within 30 seconds of server time.

UDX-Access-SignatureAPI key · headerrequired

Standard-base64 RSA-PSS/SHA-256 signature with a 32-byte salt.

AuthorizationBearer token (JWT) · headerrequired

Bearer token for an active signed-in UDX user.

Header parameters

UDX-Versionstring

Dated API version (YYYY-MM-DD).

min length 10 · max length 10

Path parameters

order_idEntityIdrequired

Exchange-assigned order identifier.

min length 1

Responses

200The requested order.

orderOrderrequired

An order.

Show properties

order_idEntityIdrequired

An exchange-assigned identifier. Treat it as an opaque, stable key with no internal structure.

min length 1

client_order_idClientId

A client-supplied correlation identifier.

account_idstringrequired

The account the order was placed under.

min length 1

tickerTickerrequired

A human-meaningful natural key naming a single-leg or multi-leg market.

min length 1 · max length 128

sideOrderSiderequired

Order side.

Allowed:buysell

quantityFixedPointQuantityrequired

A quantity in contracts as a fixed-point decimal string.

max length 24 · matches ^[0-9]+(\.[0-9]{1,2})?$

pricestringrequired

Limit price in YES price space, in dollars, regardless of side.

max length 24 · matches ^[0-9]+(\.[0-9]{1,6})?$

time_in_forceOrderTimeInForcerequired

Order time in force.

Allowed:gtciocfokdaygttunknown

expires_atstring<date-time>

When the order expires. Present only when time_in_force is gtt.

max length 40

statusOrderStatusrequired

An order's status.

Allowed:restingpartially_filledfilledcanceledexpiredrejected

rejection_reasonstring

Why the exchange rejected the order. Present only when status is rejected.

Allowed:duplicate_client_order_idself_trade_preventedmarket_closedinsufficient_fundsprice_out_of_boundsquantity_out_of_boundspost_only_would_crossno_liquidityquote_unavailablequote_terms_mismatchquote_already_acceptedrate_limitedexpires_at_invalidexchange_rejected

filled_quantitystringrequired

The quantity of the order that has been filled.

max length 24 · matches ^[0-9]+(\.[0-9]{1,2})?$

remaining_quantitystringrequired

The quantity of the order that is currently resting.

max length 24 · matches ^[0-9]+(\.[0-9]{1,2})?$

average_fill_pricestring

Volume-weighted average fill price. Present when filled_quantity > 0.

max length 24 · matches ^[0-9]+(\.[0-9]{1,6})?$

fees_paidstringrequired

Total fees collected on the order so far, in dollars.

max length 24 · matches ^[0-9]+(\.[0-9]{1,6})?$

created_atstring<date-time>required

When the order was created.

max length 40

401No valid credential was provided.

typestring<uri-reference>required

A stable URN identifying the kind of problem, for example urn:udx:problem:insufficient-permissions. Branch on it rather than on the localized detail. It is an identifier, not a URL to dereference.

max length 2048

titlestringrequired

A localized, human-readable summary of the error category. Stable for a given status code and resolved language — clients must not use it as a machine-readable discriminator.

max length 40

statusintegerrequired

The HTTP status code, repeated from the response itself.

detailstring

A localized, human-readable explanation specific to this occurrence. Clients must not parse it for machine-readable information.

max length 500

instancestring<uri-reference>

An identifier for this specific occurrence, so it can be correlated with server-side logs if you need to report it.

max length 100

403The credential lacks the read scope.

typestring<uri-reference>required

A stable URN identifying the kind of problem, for example urn:udx:problem:insufficient-permissions. Branch on it rather than on the localized detail. It is an identifier, not a URL to dereference.

max length 2048

titlestringrequired

A localized, human-readable summary of the error category. Stable for a given status code and resolved language — clients must not use it as a machine-readable discriminator.

max length 40

statusintegerrequired

The HTTP status code, repeated from the response itself.

detailstring

A localized, human-readable explanation specific to this occurrence. Clients must not parse it for machine-readable information.

max length 500

instancestring<uri-reference>

An identifier for this specific occurrence, so it can be correlated with server-side logs if you need to report it.

max length 100

404No order with this ID exists or is visible to the caller.

typestring<uri-reference>required

A stable URN identifying the kind of problem, for example urn:udx:problem:insufficient-permissions. Branch on it rather than on the localized detail. It is an identifier, not a URL to dereference.

max length 2048

titlestringrequired

A localized, human-readable summary of the error category. Stable for a given status code and resolved language — clients must not use it as a machine-readable discriminator.

max length 40

statusintegerrequired

The HTTP status code, repeated from the response itself.

detailstring

A localized, human-readable explanation specific to this occurrence. Clients must not parse it for machine-readable information.

max length 500

instancestring<uri-reference>

An identifier for this specific occurrence, so it can be correlated with server-side logs if you need to report it.

max length 100

429The member rate limit was exceeded.

typestring<uri-reference>required

A stable URN identifying the kind of problem, for example urn:udx:problem:insufficient-permissions. Branch on it rather than on the localized detail. It is an identifier, not a URL to dereference.

max length 2048

titlestringrequired

A localized, human-readable summary of the error category. Stable for a given status code and resolved language — clients must not use it as a machine-readable discriminator.

max length 40

statusintegerrequired

The HTTP status code, repeated from the response itself.

detailstring

A localized, human-readable explanation specific to this occurrence. Clients must not parse it for machine-readable information.

max length 500

instancestring<uri-reference>

An identifier for this specific occurrence, so it can be correlated with server-side logs if you need to report it.

max length 100

500Something went wrong on UDX's side.

typestring<uri-reference>required

A stable URN identifying the kind of problem, for example urn:udx:problem:insufficient-permissions. Branch on it rather than on the localized detail. It is an identifier, not a URL to dereference.

max length 2048

titlestringrequired

A localized, human-readable summary of the error category. Stable for a given status code and resolved language — clients must not use it as a machine-readable discriminator.

max length 40

statusintegerrequired

The HTTP status code, repeated from the response itself.

detailstring

A localized, human-readable explanation specific to this occurrence. Clients must not parse it for machine-readable information.

max length 500

instancestring<uri-reference>

An identifier for this specific occurrence, so it can be correlated with server-side logs if you need to report it.

max length 100

503Request admission or account setup is unavailable, or the read could not be completed in time; retry.

typestring<uri-reference>required

A stable URN identifying the kind of problem, for example urn:udx:problem:insufficient-permissions. Branch on it rather than on the localized detail. It is an identifier, not a URL to dereference.

max length 2048

titlestringrequired

A localized, human-readable summary of the error category. Stable for a given status code and resolved language — clients must not use it as a machine-readable discriminator.

max length 40

statusintegerrequired

The HTTP status code, repeated from the response itself.

detailstring

A localized, human-readable explanation specific to this occurrence. Clients must not parse it for machine-readable information.

max length 500

instancestring<uri-reference>

An identifier for this specific occurrence, so it can be correlated with server-side logs if you need to report it.

max length 100

Request

curl -X GET "https://api.underdogexchange.com/orders/6820943174116859281" \
  -H "UDX-Access-Key: API_KEY_ID" \
  -H "UDX-Access-Timestamp: UNIX_MILLISECONDS" \
  -H "UDX-Access-Signature: BASE64_SIGNATURE"

Response

{
  "order": {
    "order_id": "BK9BZNTK8022",
    "client_order_id": "order-20260804-001",
    "account_id": "6820943174116859281",
    "ticker": "UDX-EXAMPLE-MARKET",
    "side": "buy",
    "quantity": "100",
    "price": "0.55",
    "time_in_force": "gtc",
    "status": "filled",
    "filled_quantity": "100",
    "remaining_quantity": "0",
    "average_fill_price": "0.55",
    "fees_paid": "0.55",
    "created_at": "2026-01-01T00:00:00.000000Z"
  }
}

{
  "type": "urn:udx:problem:invalid-authentication-credentials",
  "title": "Unauthorized",
  "status": 401,
  "detail": "invalid authentication credentials",
  "instance": "urn:request-id:8f14e45f-ceea-4abc-a743-e89a34d3f6ef"
}

{
  "type": "urn:udx:problem:insufficient-permissions",
  "title": "Forbidden",
  "status": 403,
  "detail": "insufficient permissions",
  "instance": "urn:request-id:8f14e45f-ceea-4abc-a743-e89a34d3f6ef"
}

{
  "type": "urn:udx:problem:member-rate-limit-exceeded",
  "title": "Too Many Requests",
  "status": 429,
  "detail": "this member has temporarily exceeded its request rate",
  "instance": "urn:request-id:8f14e45f-ceea-4abc-a743-e89a34d3f6ef"
}

{
  "type": "urn:udx:problem:projection-unavailable",
  "title": "Service Unavailable",
  "status": 503,
  "detail": "account setup is still being completed; retry later",
  "instance": "urn:request-id:8f14e45f-ceea-4abc-a743-e89a34d3f6ef"
}

{
  "type": "urn:udx:problem:request-admission-unavailable",
  "title": "Service Unavailable",
  "status": 503,
  "detail": "request admission is temporarily unavailable",
  "instance": "urn:request-id:8f14e45f-ceea-4abc-a743-e89a34d3f6ef"
}

{
  "type": "urn:udx:problem:could-not-process-retry",
  "title": "Service Unavailable",
  "status": 503,
  "detail": "could not process request, please retry",
  "instance": "urn:request-id:8f14e45f-ceea-4abc-a743-e89a34d3f6ef"
}