Mempool

Mempool Transaction

Lookup a transaction currently in the mempool.

Page Sections

GET

`/mempool/{txid}`

Full URL: https://forcex.com/xtract/v1/litecoin/mempool/{txid}

Credit cost: 1 credit.

curl -H "Authorization: Bearer fx_test_************" \
  "https://forcex.com/xtract/v1/litecoin/mempool/781ad15bf1b36228b0e4ea81376379a3fa65b02d16d2432ae3a0ae4cc8af5765"

Parameters

Name	Location	Required	Type	Description
`txid`	path	yes	string	—

Request Body

No request body.

Example Response

Representative trimmed response. Use the OpenAPI schema for the exhaustive field contract.

{
  "data": {
    "txid": "781ad15bf1b36228b0e4ea81376379a3fa65b02d16d2432ae3a0ae4cc8af5765",
    "fee_atomic_units": 2200,
    "vsize": 141,
    "first_seen_at": "2026-06-03T17:19:21Z"
  },
  "meta": {
    "served_from": "node",
    "credit_cost": 1
  }
}

Documented Responses

Status	Description
`200`	Successful Response
`400`	Bad request. The `error.code` field identifies the specific cause: `bad_request` (general validation failure, including malformed dates, out-of-order ranges, and request-body validation), `range_too_large` (date range exceeds the per-grain cap), `ambiguous_time_range` (legacy `from`/`to` and new `start`/`end` supplied with differing values), or `invalid_include` (unsupported expansion in `?include=`).
`401`	Authentication required, or the supplied Bearer token is invalid or revoked. `error.code` = `auth_required`.
`402`	Payment-tier gate. `error.code` identifies which gate fired: `subscription_required` (no active subscription on the account), `subscription_inactive` (subscription exists but is not active), `include_all_requires_paid_tier` (sandbox keys cannot request `?include=all`), `include_set_requires_paid_tier` (the requested include set exceeds the per-request cost cap for sandbox keys), `historical_scan_requires_paid_tier` (sandbox keys cannot scan outside the recent window), or `deep_pagination_requires_paid_tier` (sandbox keys cannot page beyond the depth cap).
`403`	Authenticated but the key lacks the required scope. `error.code` = `scope_insufficient`.
`404`	Entity not found. `error.code` = `not_found`. Returned on direct entity GETs only — the `/chain/search` endpoint returns 200 with an empty/`not_found`-shaped body instead.
`422`	Defense-in-depth: the runtime maps standard request-shape validation errors to 400, so partners normally see 400 instead of 422. This status is declared so any edge-case validation path that bypasses the override is still typed.
`429`	Rate limit or credit budget exceeded. `error.code` identifies the window: `rate_limit_exceeded` (per-second or per-minute), `quota_exceeded_daily` (sandbox per-day budget), or `quota_exceeded` (per-subscription-period). The body carries a `window` field (`second`, `minute`, `day`, or `month`) naming the failing limit. Responses include the standard `Retry-After` header.
`500`	Internal server error. `error.code` = `internal_error`. Reference `meta.request_id` when contacting support.
`502`	Upstream Litecoin node was reached but returned an error or a non-2xx status (connection failure, timeout, or error payload). `error.code` = `upstream_unavailable`. Returned only on routes that read live node state: the mempool routes (`/mempool`, `/mempool/{txid}`) and `/chain/home` when `?include=mempool` is set.
`503`	Service or downstream data store is temporarily unavailable, or the endpoint is not implemented in this API version. `error.code` identifies the cause: `data_unavailable` (chain tip not yet populated), `audit_unavailable` (request completed but audit could not be acknowledged — safe to retry), `plan_misconfigured` (operational issue on the API side; not a tier problem), or `endpoint_not_available` (the route is reserved and not yet served in this version).

Integration Notes

Returns `404 not_found` when the transaction is not currently in the mempool.
This endpoint is node-backed and may surface `502 upstream_unavailable`.