agents-u-cash (Python)

Zero-dependency Python client for the agents.u.cash API - the 402 Online Protocol for non-custodial agent payments. Works for both sides of the network: an agent selling (manage resources, watch settlements) and a buyer (fetch a 402 door, pay, and settle - automatically via on-chain detection, or instantly by submitting the tx hash). Supports ~40 native coins (Bitcoin + Lightning, Ethereum + 15 EVM L2s, Solana, Tron, XRP, USDT/USDC, USDC-on-Base gasless, UCASH) plus custom tokens on 20 chains (ERC-20 / TRC-20 / SPL / ...) - see agents.u.cash for the full live list.

Uses only the standard library (urllib). No dependencies. Python 3.7+.

Install

pip install agents-u-cash

Or copy agents_u_cash.py - it has no dependencies.

Sell (as an agent)

from agents_u_cash import AgentsUCash

# Get an API key once (wallet-first; works at $0 immediately - verify email optionally for free credit):
# key = AgentsUCash().signup(email="me@agent.dev", password="longpass")["api_key"]

agent = AgentsUCash(api_key="...")
agent.set_wallet("btc", "bc1q…")
agent.set_webhook("https://my.bot/webhook")

res = agent.create_resource(amount=0.05)               # priced resource
acc = agent.create_challenge(res["res_id"])             # what a buyer pays
# Share the payable link: https://agents.u.cash/r/{res_id}

settled = agent.get_settlements()                       # your earnings log

Buy (as a buyer)

from agents_u_cash import AgentsUCash

buyer = AgentsUCash()                                   # no key needed to buy
door = buyer.view_door(res_id)                          # the 402 door (JSON)
# 1. pick an entry, pay entry["payTo"] exactly entry["amount"] from your wallet (out of band)
# 2. the platform auto-detects the on-chain payment and settles it.
#    Optionally POST the tx hash to settle instantly instead:
result = buyer.verify(door["accepts"][0]["challengeId"], tx_hash)
# -> {"settled": True} | {"status": "pending", "confirmations": n, "required": m}

A human-friendly payable page is also available: buyer.view_door(res_id, html=True) returns the HTML.

UCP checkout sessions (buyer)

Multi-item, mixed-currency carts over the Universal Commerce Protocol. The merchant is resolved from the custom-domain base_url, or from a cloud merchant token on the shared host. No API key.

buyer = AgentsUCash()   # base_url = the merchant's domain (or the platform host + cloud)
cart = buyer.create_checkout(
    line_items=[{"item": {"id": res_id_a}, "quantity": 1}, {"item": {"id": res_id_b}, "quantity": 2}],
    currency="USD",            # optional: cart currency for mixed-currency carts
    cloud="<merchant-token>",  # only on the shared platform host
)
# -> {"id": ..., "status": "incomplete", "currency", "line_items", "totals", "ap2": {"merchant_authorization", "nonce"}}
ready = buyer.complete_checkout(cart["id"], cloud="<merchant-token>")
# -> ready_for_complete + payment_handlers[] (pay each challenge on-chain)
order = buyer.get_order(cart["id"], cloud="<merchant-token>")   # per-item fulfillment status

Optional AP2 (dev.ucp.shopping.ap2_mandate): pass complete_checkout(id, ap2={"checkout_mandate": ...}, cloud=...) with a buyer-signed SD-JWT-VC for holder-proof authorization. Responses are RFC 9421-signed (ES256) with the merchant key.

Manage your store (full merchant surface)

Beyond priced 402 resources, an agent is a first-class merchant over its own account: full transaction history + actions, multi-store, shop products, landers, payout-info/OTC, discount codes, checkout custom fields, and billing. All key-authenticated; tenant-scoped to the agent.

# Transactions: full history, CSV export, + actions
txs = agent.get_transactions(status="C", limit=50)
csv = agent.download_transactions(date_from="2026-01-01")     # raw CSV text
agent.refund_transaction(tx_id)        # self-guarding: only if you connected a refund-capable node/coinbase
agent.resend_webhook(tx_id)
agent.submit_hash(tx_id, "0xabc...")

# Stores (sub-merchants)
store = agent.create_store(label="Store B")  # api_key+cloud_token+webhook_secret returned once
agent.rotate_store_credential(store["store"]["id"], "cloud_token")

# Shop products, landers, payout-info/OTC
agent.create_shop_product(title="Ebook", price=9.99, currency="USD")
agent.create_lander(checkout_id=flag_id)
agent.create_payout_info(amount=50, currency="USD", email="payee@x.dev")  # emails the payee a link

# Discount codes (amount = price multiplier: 0.9 = 10% off) + checkout custom fields
agent.add_discount_code(code="LAUNCH", amount=0.9, checkout_ids="all")
agent.add_custom_field(type="select", label="Size", options=["S", "M", "L"])

# Billing: balances + capacity
bill = agent.get_billing()             # {credit_balance, ucash_points, lander_slots:{...}}
agent.buy_lander_pack(10)              # debits credit_balance, grows slots
agent.redeem_ucash(1000)               # UCASH points -> fee credit

Subagents (scoped RBAC keys)

Delegate a LIMITED credential to another automated principal. A subagent is a scoped sa_ API key with a staff role: it authenticates against your tenant, but the existing RBAC (uxc_can) enforces a limited capability set on every endpoint, so it can only do what the role allows. Owner-only (you create them; a subagent cannot create subagents). Reuses the merchant staff model + seat billing (a subagent with no free slot debits credit_balance).

# Built-in role: a clerk can create resources + read, but not edit settings, refund, or manage stores
sub = agent.create_subagent(role="clerk", display_name="Fulfillment bot")
# sub["api_key"] is the sa_ key, returned ONCE. The key works on every /v1/* endpoint; writes its role
# lacks return 403, and managing stores stays owner-only.

# Or a custom permission set (slugs: transactions.view, checkouts.edit, payment-links.create, ...).
# store_scope (store ids) restricts it to those stores (empty = all stores).
ro = agent.create_subagent(
    role="custom", permissions=["transactions.view", "checkouts.view"], store_scope=[store_id]
)

agent.get_subagents()                                  # list (never returns the api_key)
agent.update_subagent(sub["subagent"]["id"], role="manager", status="suspended")
fresh = agent.rotate_subagent_key(sub["subagent"]["id"])   # old key stops working; new key ONCE
agent.delete_subagent(sub["subagent"]["id"])           # key stops working; seat slot frees

Spend caps (per-caller limits)

Cap how much a single payer can spend on a resource in a rolling window. A payer whose settled spend in the window reaches amount is refused new authorization (x402 before-charge; on detect the platform refuses to credit an over-cap payment). Caller identity is the payer wallet. Optional; off by default.

res = agent.create_resource(amount=0.05, currency="USD", max_per_caller={"amount": 1.00, "window_hours": 24})
agent.set_resource_cap(res["res_id"], {"amount": 0.50, "window_hours": 6})  # change it
agent.set_resource_cap(res["res_id"], None)                                  # clear it
callers = agent.get_resource_callers(res["res_id"])                          # [{caller, spend, payments}]

API

All calls return the parsed response dict and raise AgentsUCashError on API errors (which carries .code and .status).

Error handling

from agents_u_cash import AgentsUCash, AgentsUCashError

try:
    agent.create_resource(amount=0.05)
except AgentsUCashError as e:
    print(e.code, e.status, e)   # e.g. 'uxc_agent_not_activated' 402 ...

Non-custodial: the platform never holds funds - every payTo is the seller's own wallet, and this client never sees your wallet keys.