> ## Documentation Index > Fetch the complete documentation index at: https://nexus.gerowallet.io/docs/llms.txt > Use this file to discover all available pages before exploring further. # List transactions for many payment credentials in one call > Distinct transactions touching any address under each of up to 25 payment credentials, newest first, within an optional slot window. The limit applies PER CREDENTIAL, not to the response as a whole, so one busy credential cannot crowd the others out of the batch. Every requested credential appears in the response, in request order, with an empty transactions array when it has no history in the window. Served by cardano-db-sync direct SQL where a db-sync datasource is configured for the network, and by YACI elsewhere. On the db-sync path the whole batch is ONE query, so it is bounded by one query timeout rather than one per credential; a batch containing a credential busy enough to exceed that timeout returns 504 for the whole batch, so split such a credential into its own request. ## OpenAPI ````yaml https://nexus.gerowallet.io/v3/api-docs post /api/addresses/cred/transactions openapi: 3.1.0 info: title: Nexus API description: >- Multi-chain blockchain data API for Cardano (and Apex), Bitcoin, and Midnight. ## Blockchains & Networks Endpoints are grouped by **blockchain**. Pick the target **network** with the `network` query parameter. A network is an environment *within* a blockchain, not a separate endpoint family. - **Cardano & Apex**: one shared set of UTxO endpoints serves `CARDANO_MAINNET`, `CARDANO_PREPROD`, `CARDANO_PREVIEW`, `APEX_PRIME_MAINNET`, `APEX_VECTOR_MAINNET`, `APEX_VECTOR_TESTNET` - **Bitcoin**: `BITCOIN_MAINNET`, `BITCOIN_TESTNET4` - **Midnight**: `MIDNIGHT_MAINNET`, `MIDNIGHT_PREPROD`, `MIDNIGHT_STAGENET` These are the values published on each operation's `network` schema, and what generated clients send. A kebab-case alias (`cardano-mainnet`) is also accepted, and matching is case-insensitive — see the note on the parameter itself. ### Key scope: one chain, one network Each API key is scoped to **one chain and one network**, fixed at creation time. A `CARDANO_MAINNET` key cannot query `CARDANO_PREPROD`, and it cannot query Bitcoin or Midnight at all. Create one key per chain and network under the same account. Sending a `network` value that does not match the key returns **400 Network Mismatch**; omit the parameter and the request runs against the key's own network. What is uniform across chains is the integration surface, not the credential: one account, one base URL, one auth header, one docs site. ## Authentication Send your API key in the `X-Api-Key` header. This is the credential for programmatic access (create one in the dashboard; keys start with `nxs_`). `Authorization: Bearer ` is only for JWT **session** tokens issued by `/api/auth/login` (browser/mobile apps), not for API keys. ## Add-ons Capability is gated separately from network scope. Market data, wallet analytics, transaction building, MCP, and IPFS are paid add-ons; those endpoints return **402 Payment Required** on a key whose plan does not carry the matching add-on, even when the chain and network match. contact: name: Nexus Team url: https://nexus.gerowallet.io/support email: nexus@gerowallet.io license: name: Apache 2.0 url: https://www.apache.org/licenses/LICENSE-2.0.html version: 1.0.0 servers: - url: https://nexus.gerowallet.io description: API Server security: - apiKeyAuth: [] - bearerAuth: [] tags: - name: Cardano · Blocks description: Cardano Block API - name: Cardano · Policy description: Cardano Policy API - name: IPFS description: IPFS Content Resolution API - name: Bitcoin · Ordinals description: Ordinals + runes metadata (ord indexer) - name: Partner description: Aggregator revenue share for partner key holders - name: Cardano · Metadata description: Label-scoped transaction metadata API - name: Cardano · Assets description: Token Registry Metadata - name: Cardano · Transactions description: Cardano Transactions API - name: Midnight · Transactions description: Midnight-specific transaction endpoints (unshielded UTXOs) - name: Bitcoin · Mempool description: Bitcoin mempool snapshot - name: Midnight · DUST description: DUST registration + generation status - name: Cardano · Stake Pools description: >- Cardano stake pool information including registrations, retirements, and pool metadata - name: Cardano · Network description: Cardano Network API - Query static network / genesis parameters - name: Cardano · Addresses description: Cardano Address API - name: Bitcoin · Addresses description: >- Bitcoin address-keyed queries: stats / balance / UTxOs via electrs; ordinals via ord - name: Bitcoin · Transactions description: Bitcoin transaction lookup and submission - name: Cardano · Governance description: >- Cardano on-chain governance: DReps, governance actions + votes, constitutional committee, constitution - name: Cardano · DReps description: >- Cardano delegate representatives (DReps): voting power, status, metadata, delegators - name: Cardano · Transaction Builder description: >- Cardano transaction building API. Builds unsigned transactions server-side for client-side signing and submission. Network can be specified in the request body or as a query parameter. Body takes precedence over query parameter. - name: Cardano · Assets description: Cardano Asset API - name: Cardano · Accounts description: Cardano Account API - name: Bitcoin · Fees description: Bitcoin fee-rate estimates by confirmation block target - name: Bitcoin · Blocks description: Bitcoin block lookup - name: Cardano · Handles description: ADA Handle resolution - name: Cardano Market Data description: Endpoints from cardano-market-data - name: Midnight · Indexer description: Transparent proxy to the Midnight GraphQL indexer - name: Cardano · Scripts description: Cardano script & datum API - name: Cardano · Epochs description: Cardano Epoch API - Query protocol parameters and epoch information - name: Bitcoin · Chain description: Bitcoin chain-tip and sync state paths: /api/addresses/cred/transactions: post: tags: - Cardano · Addresses summary: List transactions for many payment credentials in one call description: >- Distinct transactions touching any address under each of up to 25 payment credentials, newest first, within an optional slot window. The limit applies PER CREDENTIAL, not to the response as a whole, so one busy credential cannot crowd the others out of the batch. Every requested credential appears in the response, in request order, with an empty transactions array when it has no history in the window. Served by cardano-db-sync direct SQL where a db-sync datasource is configured for the network, and by YACI elsewhere. On the db-sync path the whole batch is ONE query, so it is bounded by one query timeout rather than one per credential; a batch containing a credential busy enough to exceed that timeout returns 504 for the whole batch, so split such a credential into its own request. operationId: getTransactionsByPaymentCredentials parameters: - name: network in: query required: false schema: type: string description: >- Accepts either the value listed here (`CARDANO_MAINNET`) or its kebab-case alias (`cardano-mainnet`); matching is case-insensitive. Omit it and the network is taken from the API key. A value that disagrees with the key's own network returns 400 Network Mismatch. enum: - CARDANO_MAINNET - CARDANO_PREPROD - CARDANO_PREVIEW - APEX_PRIME_MAINNET - APEX_VECTOR_MAINNET - APEX_VECTOR_TESTNET - MIDNIGHT_MAINNET - MIDNIGHT_PREPROD - MIDNIGHT_STAGENET - BITCOIN_MAINNET - BITCOIN_TESTNET4 - name: fromSlot in: query required: false schema: type: integer format: int64 - name: toSlot in: query required: false schema: type: integer format: int64 - name: limit in: query description: >- Transactions per credential, applied to each credential independently required: false schema: type: string default: '' maximum: 200 minimum: 1 requestBody: content: application/json: schema: $ref: '#/components/schemas/BulkCredentialsRequest' required: true responses: '200': description: Transactions per credential content: application/json: schema: type: array additionalProperties: default: '' contains: default: '' items: $ref: '#/components/schemas/CredentialTransactionsDto' default: '' unevaluatedItems: default: '' '400': description: >- Empty list, more than 25 credentials, a malformed credential, or an out-of-range limit content: '*/*': schema: type: array items: $ref: '#/components/schemas/CredentialTransactionsDto' '501': description: No YACI datasource configured for the network content: '*/*': schema: type: array items: $ref: '#/components/schemas/CredentialTransactionsDto' '503': description: The chain-database connection pool was saturated; retry content: '*/*': schema: type: array items: $ref: '#/components/schemas/CredentialTransactionsDto' '504': description: >- The batch did not complete within the read query timeout (10s by default) content: '*/*': schema: type: array items: $ref: '#/components/schemas/CredentialTransactionsDto' components: schemas: BulkCredentialsRequest: type: object default: null description: Bulk payment-credential lookup request properties: credentials: type: array default: '' description: Payment credential hashes, 56 hex chars each, max 25 per call example: - 87be75696aea59b41b36415d0b7c8b7a0c21fe3dd5a63939acfbc3a0 items: type: string pattern: ^[0-9a-fA-F]{56}$ maxItems: 25 minItems: 0 required: - credentials CredentialTransactionsDto: type: object default: null description: Transactions touching one payment credential properties: credential: type: string default: '' description: The payment credential exactly as it appeared in the request example: 87be75696aea59b41b36415d0b7c8b7a0c21fe3dd5a63939acfbc3a0 transactions: type: array default: '' description: >- Distinct transactions touching any address under the credential, newest first, capped at the request's limit for this credential alone. Empty when the credential has no history in the window. items: $ref: '#/components/schemas/CredentialTransactionDto' CredentialTransactionDto: type: object properties: txHash: type: string slot: type: integer format: int64 blockHeight: type: integer format: int32 blockTime: type: integer format: int64 epoch: type: integer format: int32 securitySchemes: apiKeyAuth: type: apiKey description: >- ### API key (programmatic access — recommended) Send your API key in the `X-Api-Key` header. Keys start with `nxs_` and are created in the dashboard (or via **POST /api/keys** with a session JWT). Each key is scoped to **one chain and one network** (for example `CARDANO_MAINNET`), fixed at creation time. It cannot query a different network on the same chain, and it cannot query a different chain at all. A mismatched `network` parameter returns **400 Network Mismatch**. Create one key per chain and network under the same account. This is the credential most integrations should use. name: X-Api-Key in: header bearerAuth: type: http description: >- ### JWT session token (browser / mobile apps) A short-lived JWT issued by `/api/auth/login` or `/api/auth/device`, sent as `Authorization: Bearer `. This is the **session** credential for the web dashboard and mobile apps, not for server-to-server API access. For programmatic API access use an **API key** in the `X-Api-Key` header instead — do **not** put an `nxs_` API key in this Bearer field. scheme: bearer bearerFormat: JWT ````