Call any capability. Pay per call.

The fastest way to onboard: tell your agent to read the skill and run a task. It creates a wallet, funds it with Base USDC, and starts calling tools on its own.

Under the hood that's three steps — install, fund, call:

# 1. Install the CLI (bundles the OWS wallet binary)
npm i -g @h402/cli

# 2. Create a local wallet (passphrase-less by default), then fund it with a few $ of Base USDC
h402 wallet create --name agent
#   -> {"wallet":{"name":"agent","address":"0x..."}}
#   send Base USDC to that address (or run: h402 wallet fund --name agent)
h402 wallet balance --name agent

# 3. Find a task and call it — pays per call automatically, returns JSON
h402 search "web search"
h402 call web/search --name agent --json '{"query":"agent payments"}'

Every command prints JSON to stdout and runs non-interactively out of the box — wallets are passphrase-less by default, so nothing prompts. Only if you opted a wallet into a passphrase at create time, set H402_WALLET_PASSPHRASE (the CLI says so when it hits such a wallet). Most capabilities cost $0.001–$0.05 per call, so a few dollars of USDC lasts a long time.

Calls are paid per request in Base USDC over x402 — non-custodial, with keys staying on your machine. The CLI handles the whole exchange for you:

Reuse an idempotency-key on a retry — h402 dedupes by it, so a resent paid request never double-charges.

Capabilities are task-first: category/action. Browse the catalog, search it from the CLI, or query the API directly.

h402 search "token holders"     # CLI — JSON matches
curl https://h402-test.hunt.town/api/catalog    # compact task index as JSON
curl https://h402-test.hunt.town/api/catalog/routes/web/search    # provider contracts for one task

When --provideris omitted, the CLI resolves the task's current default for that invocation and prints the provider-pinned command it used. It does not store that choice. Raw HTTP always uses /routes/{provider}/category/action; change that provider only when you choose to switch contracts.

# With the CLI (handles signing + retry for you)
h402 call web/search --json '{"query":"agent payments"}'

# Raw HTTP — the first call returns 402, then retry with the signature
curl -X POST https://h402-test.hunt.town/routes/tempo-firecrawl/web/search \
  -H 'content-type: application/json' \
  -H 'idempotency-key: <uuid>' \
  -d '{"query":"agent payments"}'
# -> 402 PAYMENT-REQUIRED; sign the challenge and retry with PAYMENT-SIGNATURE.
#    Reuse the same idempotency-key on the paid retry — h402 never double-charges.

A successful call returns { data, meta?, h402 }: data is the provider-native body, optional meta carries provider metadata, and h402 is the call receipt — the pinned provider, payment mode, provider-native async handle/status metadata, and a followUp block with the exact provider-pinned poll path. Errors return an { error } envelope (with the raw upstream body when a provider rejected the call) and a non-2xx status.

If you run h402 auth with your wallet, bonus credits draw down before USDC; pass --no-credit to force x402.

For a custom (non-CLI) integration, import @h402/core — the signer-agnostic protocol toolkit. It builds the x402 challenge and the EIP-3009 typed-data; you plug in your own signer (viem, ethers, or OWS). The @h402/cli is built on it.

npm i @h402/core