For Agents
Open and close UK bank accounts, run KYC admissions, submit payments, and query transactions through Griffin's banking-as-a-service API.
Use for: Open a new sandbox bank account on Griffin, Close a Griffin bank account, Submit a payment from a specific Griffin bank account, List the last 100 transactions on a Griffin account
Not supported: Does not handle card processing, accounting, or tax filing - use for UK banking-as-a-service operations on accounts, payments, transactions, and KYC only.
Griffin is a UK banking-as-a-service provider, and the Griffin API is the resource-oriented REST surface that exposes its banking operations. Agents can open and close bank accounts, manage legal persons (KYC subjects), submit and track payments, query transactions, look up Companies House data, run Admissions and Submissions for onboarding, and manage API keys. The API is structured as a tree under your organization with navigation links in every response and uses an Authorization header containing a Griffin-issued API key.
Install Jentic One Beta
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the The Griffin API, or any other public or private API you need. You set the rules, the agent never sees your credentials, and every call is logged.
Two steps, two machines. Install the instance in a safe environment, then register your agent from wherever it runs.
Step 1: Jentic One Host machine
# On the machine that will host your Jentic One instance:
curl -fsSL "https://jentic.com/install.sh?src=apis&api=%2Fapis%2Fgriffin.com%2Fgriffin" | shStep 2: Agent machine
# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL "https://jentic.com/install.sh?src=apis&api=%2Fapis%2Fgriffin.com%2Fgriffin" | sh
jentic register # connects your agent to your Jentic One instanceJentic One is in public beta. The setup above keeps your agent separate from the instance, which is what you want before using real credentials: an agent running as the same OS user as Jentic One can read its stored keys directly. Just evaluating? A single local install is fine to start. See the secure deployment guide for the tiers.
What an agent can do with The Griffin API.
Open and inspect bank accounts under an organisation with /v0/bank/accounts/{bank-account-id}
Close a bank account via POST /v0/bank/accounts/{bank-account-id}/actions/close
Create and list payments on an account with /v0/bank/accounts/{bank-account-id}/payments
Read individual transactions through GET /v0/bank/transactions/{transaction-id}
GET STARTED
Run KYC admissions and inspect their status with /v0/admissions/{admission-id}
Look up UK companies via GET /v0/companies-house/companies/{company-number}
Manage API keys for the organisation through /v0/api-keys/{api-key-id}
Patterns agents use The Griffin API for, with concrete tasks.
★ Embedded Banking Onboarding
Run a customer through KYC and then provision a Griffin bank account. The agent submits an admission, polls /v0/admissions/{admission-id} until the decision lands, then opens a bank account scoped to the approved legal person. Griffin's tree-shaped API exposes the navigation links inline, so agents can follow them without hard-coding paths.
Submit an admission for the customer, poll GET /v0/admissions/{admission-id} until decided, then open the bank account through the navigation link returned in the admission response.
Payment Initiation and Reconciliation
Initiate a UK payment from a Griffin bank account and reconcile it against the inbound transaction record. The agent calls POST /v0/bank/accounts/{bank-account-id}/payments to submit, GET /v0/bank/accounts/{bank-account-id}/payments to list, and GET /v0/bank/transactions/{transaction-id} to confirm settlement. This avoids stitching together separate payment and ledger tools.
Call POST /v0/bank/accounts/{bank-account-id}/payments with the payee details and amount, then poll the payment record until status reaches 'settled' and link the matching transaction.
Companies House Data Enrichment
Enrich a customer profile with UK Companies House data without bolting on a separate provider. GET /v0/companies-house/companies/{company-number} returns the company record direct from Griffin's enrichment proxy, useful during business account onboarding.
Given a company number from a signup form, call GET /v0/companies-house/companies/{company-number} and attach the registered address and officers to the case file.
AI Agent Treasury Assistant
An internal treasury agent uses Griffin to action payments approved by humans. The user says 'pay supplier X £4,500 from the operating account' and the agent searches Jentic for the right Griffin operation, loads the schema, executes the call against the correct account, and reports the payment ID back.
Search Jentic for 'submit a payment from a Griffin bank account', load the POST /v0/bank/accounts/{bank-account-id}/payments schema, execute it with the named account ID and payee details, and return the payment ID.
69 endpoints — griffin is a uk banking-as-a-service provider, and the griffin api is the resource-oriented rest surface that exposes its banking operations.
METHOD
PATH
DESCRIPTION
/v0/index
Bootstrap the API tree with the organisation URL
/v0/bank/accounts/{bank-account-id}
Get a bank account
/v0/bank/accounts/{bank-account-id}/actions/close
Close a bank account
/v0/bank/accounts/{bank-account-id}/payments
Submit a payment
/v0/bank/accounts/{bank-account-id}/transactions
List transactions on an account
/v0/bank/transactions/{transaction-id}
Get a single transaction
/v0/admissions/{admission-id}
Get KYC admission status
/v0/companies-house/companies/{company-number}
UK Companies House lookup
/v0/index
Bootstrap the API tree with the organisation URL
/v0/bank/accounts/{bank-account-id}
Get a bank account
/v0/bank/accounts/{bank-account-id}/actions/close
Close a bank account
/v0/bank/accounts/{bank-account-id}/payments
Submit a payment
/v0/bank/accounts/{bank-account-id}/transactions
List transactions on an account
/v0/bank/transactions/{transaction-id}
Get a single transaction
/v0/admissions/{admission-id}
Get KYC admission status
/v0/companies-house/companies/{company-number}
What agents get from Jentic-routed access to this vendor.
Setup
Wiring The Griffin API by hand means carrying its API key in the Authorization header and mapping the bank account, payment, transaction, and admission endpoints across the v0 surface yourself. Through Jentic you install once, import The Griffin API from the API Directory, store the API key once, and your agent calls it.
Permission scoping
Griffin puts the bank account id in the URL path (/bank/accounts/{bank-account-id}/transactions, /bank/accounts/{bank-account-id}/payments), so a rule can pin your agent to one account: it can read that account's transactions and nothing else. You choose the operations it may call, so ones like sending a payment or closing an account are not included unless you add them.
Credential isolation
Your Griffin API key is stored once, encrypted, by your own Jentic One instance and injected at execution time. It never enters the agent's prompt, logs, or context.
Intent-based discovery
Agents search Jentic by intent such as 'list a bank account's transactions' or 'look up a company at Companies House', and Jentic returns the matching Griffin operation with its input schema so the agent calls the right endpoint without browsing the reference docs.
Alternatives and complements available in the Jentic catalogue.
Stripe API
Card and online payment processor - pair with Griffin to settle card revenue into a Griffin account.
Pair Stripe with Griffin when collecting card payments and holding the proceeds in an embedded UK bank account.
Specific to using The Griffin API through Jentic.
What authentication does The Griffin API use?
Griffin uses an API key in the Authorization header with the format 'GriffinAPIKey g-test-MyKey-XXXXXXX'. Through Jentic, the key is stored encrypted in your Jentic One instance and the executor injects the full Authorization header at call time.
Can I open and close UK bank accounts with this API?
Yes. Bank accounts live under the organisation tree at /v0/bank/accounts/{bank-account-id}. Closure is a dedicated action - POST /v0/bank/accounts/{bank-account-id}/actions/close - rather than a status PATCH, in line with Griffin's design choice to gate sensitive transitions behind explicit endpoints.
What are the rate limits for the Griffin API?
The OpenAPI spec does not publish explicit rate limits. Griffin applies tenant-level throttles based on the API key's plan. Production agents should handle 429 responses with exponential backoff and surface failures to the workflow.
How do I submit a payment through Jentic?
Search Jentic for 'submit a payment from a bank account', load the POST /v0/bank/accounts/{bank-account-id}/payments schema, then execute it with the bank account ID, payee, and amount. The Authorization header is injected from the vault.
Does the API support pagination on list endpoints?
Yes. List responses include a links object with prev and next URLs. Page size is controlled with the page[size] query parameter (1-200, default 25). Agents follow the next link to walk through the full result set.
How do I test the Griffin API safely?
Anyone can register at app.griffin.com/register and try the API in sandbox mode with a test API key (prefix g-test-). The same endpoints apply - the only difference is the key and that no real funds move.
Can I limit what my agent is allowed to do with the Griffin API?
Yes. Because you run Jentic One yourself and your own rules decide which operations and credentials the agent may use, you choose exactly which Griffin operations it can call. Since Griffin puts the bank account id in the URL path, such as /v0/bank/accounts/{bank-account-id}/transactions, you can pin the agent to a single account so it reads that account's transactions and nothing else. Higher-risk operations like POST /v0/bank/accounts/{bank-account-id}/payments or the close-account action are excluded unless you explicitly add them, and the encrypted API key is injected at call time rather than exposed to the agent.
UK Companies House lookup