The x402 Bazaar is Coinbase's catalog of payment-gated services that AI agents can search, compare and pay for per call. Coinbase's developer documentation describes it as a catalog of services discovered by the CDP Facilitator that can be searched by intent, browsed in full, or filtered to every resource paying a given merchant address, with no CDP API key required for discovery (Coinbase: Discover services). This explainer covers what the Bazaar indexes, the buyer and seller flows, what agents actually buy there, and what automatic discovery means for spend controls.
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Last reviewed: Nov 2026. Usage figures are dated and attributed to the party that published them.
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The x402 Bazaar is a discovery layer: a machine-readable directory of HTTP endpoints that charge through the x402 payment protocol. An agent queries it for a capability, receives a ranked list of endpoints with prices and usage data, and calls the one it wants. Payment happens through x402 itself; the Bazaar only answers the question of where to buy.
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x402 turns the HTTP 402 Payment Required status code into a payment step: the server answers an unpaid request with a price, the client pays in a stablecoin, and the client retries with proof of payment. Eco's x402 protocol explainer and HTTP-native agent payments guide cover the protocol in depth. This page stays on discovery.
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The Bazaar is not the only discovery layer. Turnkey's September 17, 2026 analysis lists Agentic.Market, Coinbase's public storefront over the same ecosystem, Agent402, an open-source MCP-native marketplace, and the PayAI and thirdweb facilitator networks as other places x402 supply is indexed (Turnkey).
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A buyer agent searches the Bazaar, picks an endpoint, calls it, receives a 402 response with a price, pays from its wallet, and retries the call with proof of payment. Discovery runs through the CDP SDK, the REST API or a Bazaar MCP server, and all three query the same public catalog.
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The CDP TypeScript SDK exports three discovery functions. searchX402Resources returns relevance-ranked matches and accepts filters for network, asset, payment scheme, payTo address, URL, maximum USD price and protocol extension. listX402DiscoveryResources browses active resources with pagination, and listX402DiscoveryMerchant lists everything paying a given address (Coinbase: Discover services).
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Search returns at most 20 resources per query, ranked by a blend of relevance and quality. Quality draws on recent call volume and unique payers plus the completeness of the description, output schema and metadata, and each result reports its 30-day call count, unique payer count and last-called time (Coinbase).
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For agents that speak MCP, Coinbase documents three Bazaar MCP tools: search_resources for semantic search over the catalog, proxy_tool_call to call a discovered resource and surface a payment-required result, and validate_endpoint for read-only diagnostics that make no payment (Coinbase: Discover and pay over MCP). Eco's MCP and payments guide explains how MCP tool calls and payments fit together in general.
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A seller gets listed by registering the Bazaar extension on an x402 resource server, declaring discovery metadata for each route, validating the endpoint, and completing one successful paid call through the CDP Facilitator. Indexing runs after that first settled payment and takes up to 15 minutes, according to Coinbase's seller documentation.
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The CDP SDK can generate a minimal extensions.bazaar declaration from a route's HTTP method and path. Routes that take query parameters, path parameters or a request body need explicit schemas and examples, because without them agents can find the endpoint but cannot construct a valid call (Coinbase: Get discovered). The same page states that every validated endpoint is eligible for indexing after a settled payment, and that endpoints which stop returning 402 Payment Required are eventually removed.
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Ranking and curation are separate. Ranking orders results by economic usage and listing quality over a rolling 30-day window, and new endpoints rank conservatively until usage builds. Curation, the featured slice, requires at least 99% availability over 30 days, with priority above 99.5%, a passing health probe, agent-ready metadata and validation (Coinbase). Teams building a paid tool should also read Eco's guide to building an MCP server with x402 monetization.
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Agents mostly buy data through the Bazaar: web search, market and token data, contact enrichment, social posts and chain reads. Turnkey's analysis of the top 100 Bazaar listings over a 30-day window shows web search as the largest category by a wide margin, with crypto market data second.
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Turnkey counted 208,415 calls across those listings, 42.0% of them for web search and content retrieval and 23.4% for crypto market data and trading signals (Turnkey).
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The same post reports that between August 13 and September 13, 2026, x402 on Base recorded 44,930,157 authorized stablecoin transfers from 440,608 distinct payers, at a median payment of $0.0061 (Turnkey). Turnkey also notes that call counts and payer counts tell different stories: many crypto data feeds served a handful of addresses, while one onchain RPC balance endpoint reached 1,070 distinct payers. The breadth of real usage is narrower than raw call volume suggests.
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Automatic discovery changes the spending model. An agent that can search a catalog and pay any listed endpoint can buy from sellers its developer never reviewed. The controls that matter are a per-call price ceiling, an allowlist of networks and assets, a total budget, and a wallet policy enforced outside the model.
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Some of those controls exist at the discovery step. The maxUsdPrice, network and asset filters in Coinbase's search API keep expensive or unexpected resources out of the result set (Coinbase). But a filter applied by the agent's own code is only as reliable as that code; a prompt-injected agent can call the search without the filter. The budget has to live in the wallet layer, where the model cannot edit it. Eco's AI agent spend controls guide and prompt injection guide cover how teams separate the two.
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For agents whose purchases feed onchain actions, the same principle extends one step further. Sauce, Eco's onchain harness for agents, lets a program check balances and conditions inside the transaction that moves funds, so a transaction that would breach a stated condition reverts (Eco docs: Sauce introduction). That is a layer underneath x402 payments, not part of the Bazaar.
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The Bazaar has three practical limits today: usage is concentrated in a few categories and payers, the index depends on a single facilitator's settlement records, and quality ranking reflects past calls rather than correctness. Buyers should treat a high rank as a popularity signal, not a quality guarantee.

These answers cover the common questions about the x402 Bazaar for buyers and sellers.
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No. Coinbase states that discovery is public and the discovery APIs and SDK functions need no CDP API key (Coinbase).
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Indexing runs after a successful settled payment through the CDP Facilitator and takes up to 15 minutes (Coinbase).
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Yes. Coinbase documents a Bazaar MCP with search, proxied calls and read-only endpoint validation (Coinbase).
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No. x402 is the payment protocol; the Bazaar is one catalog of services that accept it. See x402 Protocol Explained.
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Mechanics come from Coinbase's developer documentation, fetched on November 12, 2026. Usage figures are Turnkey's analysis of Coinbase data. No calls were made to the Bazaar for this page.