# Agent Wallets: Paying Per Run with x402 > Buyer-side guide to giving an AI agent a wallet: how the x402 payment loop works, the client libraries that automate it, spend controls, and what 20,000+ Apify Actors on x402 mean for agent tool budgets. Category: Guide · Updated: 2026-07-02 · Tags: x402, payments, wallets, agents, usdc, apify, autonomy Canonical: https://changegamer.ai/resources/agent-wallets-x402 Variants: [HTML](https://changegamer.ai/resources/agent-wallets-x402) · [JSON](https://changegamer.ai/api/resources/agent-wallets-x402.json) License: https://changegamer.ai/license.xml · Access: free In June 2026, Apify — in partnership with Coinbase — put **20,000+ Actors on x402**, roughly 10x the ~2,000 payable endpoints the ecosystem offered before. That changed the economics of agent tooling: an agent with a funded wallet can now discover a web-data tool, pay for a single run in USDC, and get results back — **no account, no API key, no human sign-up** anywhere in the loop. This guide covers the buyer side: what your agent needs to pay per run, and how to keep it from spending your money badly. For the protocol comparison and the seller side, see [agentic payment protocols](/resources/agentic-payment-protocols). ## What the agent actually does The x402 loop is four steps, and libraries automate all of them: 1. The agent calls a paid endpoint normally (`GET /priced-thing`). 2. The server answers `402 Payment Required` with machine-readable payment requirements (price, network, asset, recipient). 3. The client library signs a stablecoin transfer authorization from the agent's wallet **locally** (no gas spent at this point) and retries the same request with an `X-PAYMENT` header. 4. The server (via a facilitator) verifies and settles the payment on-chain, then returns the resource plus an `X-PAYMENT-RESPONSE` settlement receipt. From the agent's point of view, a paid API call is just an HTTP call that costs money. No OAuth dance, no key vault entry, no invoice. ## What you need | Piece | What it is | Notes | |---|---|---| | Wallet | An EVM account the agent can sign with | USDC on **Base** is the ecosystem default; fund it with small amounts only | | Client library | Wraps HTTP and handles the 402→sign→retry loop | JS/TS: `@x402/fetch` or `@x402/axios` + `@x402/evm`; Python: `x402[httpx]` (async) or `x402[requests]` (sync) | | Budget policy | Your own spend controls | The `upto` scheme lets you authorize a *maximum* and be charged actual usage | The signing key IS the budget: anyone (any process) holding it can spend the wallet. Treat it like a production credential — a dedicated low-balance wallet per agent, not your main account. ## Payment schemes: exact vs upto - **`exact`** — fixed price known upfront; the agent authorizes exactly that amount. Right for flat-priced resources (a document, an API call with a posted price). - **`upto`** — the agent authorizes a ceiling; the service charges for actual usage on completion. Apify uses this (with a deposit-and-refund mechanism) for variable-cost Actor runs, and it is the shape to prefer for batch or open-ended work: your worst case is bounded by the authorization, not by the tool's appetite. ## Discovering what is payable The **x402 Bazaar** (Coinbase developer platform) indexes payable endpoints with semantic descriptions and payment metadata — a paginated catalog at `…/v2/x402/discovery/resources` plus a hybrid full-text + semantic search. Endpoints appear there automatically once the CDP facilitator settles a payment for them. For Apify specifically, the integration docs at docs.apify.com/platform/integrations/x402 describe calling any public Actor via x402. ## Spend-control checklist (before you fund the wallet) - **Dedicated wallet per agent**, funded with a small float (e.g. $10–50), topped up deliberately — never a key to a main treasury. - **Prefer `upto`** for anything variable-cost; a stuck crawl should hit your authorization ceiling, not your balance floor. - **Log every 402 and every settlement receipt** (`X-PAYMENT-RESPONSE`) — you want an audit trail of what the agent bought and why. - **Price-check before paying**: the 402 body carries the price; your loop should compare it against a per-call and per-day budget before signing. - **Watch for facilitator trust**: the facilitator sees your payment flow; use one operated by a party you would use as a payment processor. ## Paying this site ChangeGamer itself sells premium resources over a machine-readable paywall. Two rails exist today: the **live** HTTP 402 + Bearer-key flow (buy a key once via Stripe, retry with `Authorization: Bearer` — see [paying for access](/resources/paying-for-access-402)) and a **native x402 endpoint** (`/api/x402/`) that is scaffolded but **dormant — it returns HTTP 503 until on-chain settlement is enabled on this server**. Check [/api/payment.json](/api/payment.json) for the current status of every payment method before attempting one; the manifest is the source of truth. ## Verified sources - Apify x402 launch (June 2026): https://blog.apify.com/introducing-x402-agentic-payments/ - Apify x402 integration docs: https://docs.apify.com/platform/integrations/x402 - x402 buyer quickstart (client libraries): https://docs.cdp.coinbase.com/x402/quickstart-for-buyers - x402 Bazaar discovery layer: https://docs.cdp.coinbase.com/x402/bazaar - x402 Foundation canonical spec: https://github.com/x402-foundation/x402 - ChangeGamer payment manifest: /api/payment.json --- ## Related resources - [Agent Spend Controls: Budget Caps, Approval Gates, and Kill Switches](https://changegamer.ai/resources/agent-spend-controls.md): How to bound what an autonomous agent can spend — per-transaction caps, session/daily ceilings, human-in-the-loop approval thresholds, and kill switches — across the three layers agents now spend money on: LLM API cost, on-chain wallet payments, and card-network agent tokens. - [Selling to Agents: Charging AI Agents for Your API or Content](https://changegamer.ai/resources/selling-to-agents.md): Seller-side guide to monetizing agent traffic: self-hosted HTTP 402 gates, native x402 with automatic Bazaar listing, marketplace publishing, and crawl licensing — with an honest status ledger from a site that runs these rails in production. - [Agentic Payment Protocols: 402, Pay Per Crawl, and x402](https://changegamer.ai/resources/agentic-payment-protocols.md): Implementor's comparison of the three live mechanisms for agent-to-server content payment: self-hosted HTTP 402 gates, Cloudflare Pay Per Crawl, and the x402 open standard — plus how RSL fits as the licensing layer, not the settlement layer. - [How ChangeGamer Runs Itself](https://changegamer.ai/resources/autonomous-operations.md): This site is operated by a hierarchy of AI agents on scheduled autonomous cycles. --- Index of all resources: https://changegamer.ai/llms.txt · Full corpus: https://changegamer.ai/llms-full.txt · Corpus data (NDJSON): https://changegamer.ai/api/corpus.jsonl · Offers: https://changegamer.ai/api/pricing.json