Every agent-payable API.

Classifies x402 payment identifier and retry facts for duplicate-charge and privacy risk.

Maps payment rails, handlers, tokens, networks, wallet requirements, and buyer disclosures.

Explains buyer-agent approval friction for EIP-3009, Permit2, and unsupported transfer methods.

Checks sanitized order, webhook, shipment, delivery, return, refund, and adjustment facts for continuity.

x402 pre-listing QA probe: validate your endpoint's 402 challenge, header sizes, and payment schema before listing

Checks x402 price display units for decimal, atomic-unit, currency, and network consistency.

Buyer agents and marketplaces cannot quickly tell whether public release notes matter to their workflows.

Lints caller-submitted agent API, MCP, and x402 response samples for machine-actionable contract completeness without making network calls.

Creates or verifies hash-only caller-submitted x402 response provenance records with scoped idempotency and one-time lookup secrets.

x402 seller audit for a whole origin: finds your paid routes (GET and POST) in /.well-known/x402, /openapi.json and your own CDP Bazaar listings, then sends each one an unfunded test payment through your server and facilitator. Per-route verdict, exact rejection reason and a fix hint. Up to 40 routes, one payment.

Is this x402 seller real? Pass ?seller= with a host (api.example.com) or a payTo address (0x...). From Coinbase's own Bazaar counts (re-read every 6 hours) we return its listings, 30-day payers and calls, and the one number that separates customers from a test harness: how many times the average payer came back. For an Arc payTo we add its settlements from our full Arc x402 index: distinct payers and the top payer's share.

Sellers need to know whether paid-agent endpoints are priced, discoverable, converting, or leaking free access.

x402 seller trust leaderboard — every catalogue origin probed outside-in and scored 0-100, with the verdict spread and the most common reasons points were lost

Daily JSON bundles for agents from Bouncer-graded x402 sellers: crypto news beats, market structure and volatility views, price snapshots, agent trust checks, Base gas, US macro, Brazil calendar. This route serves the x402-sellers-reputation bundle.

x402 settlement inspection credit pack API — buy 10 Base/USDC settlement-analysis calls for agent payment diagnostics.

X402 Settlement Network Check: X402 Settlement Network Check compares settlement chain with the accepted challenge network from bounded caller-supplied values without an external provider. Call X402 Settlement Network Check before paying for or accepting an x402 or agent delivery assembled from caller-supplied challenge and result metadata. Returns contract-specific checks, normalized evidence, mismatch reasons, and an explicit acceptance or rejection status for X402 Settlement Network Check as…

Scores signed offer and receipt metadata for paid-service delivery confidence.

Checks whether a bounded spend permission fits a caller-supplied paid-agent workload.

x402 Starter Kit — everything an AI agent needs to start paying and earning on-chain: quickstart code, full endpoint catalog, live bounty radar + news snapshot, seller trust proof

x402 test counterparty — prove your payment stack end to end with a real settlement on Base.

x402 Top Merchants by Estimated Revenue. x402 top merchants by estimated 30-day revenue: resources, calls, top resource and its paying agents, categories and networks for every seller in Coinbase's x402 catalog.

Trust score (0-100, grade A-F) for any x402 endpoint -- listed in our catalog or not. Unlike uptime-only checkers, we return ECONOMIC PROOF: the REAL on-chain USDC settlement volume and distinct-payer count for the endpoint's payTo address -- is anyone actually paying it, or is it just live? Computed deterministically from continuous monitoring: 30d probe uptime, 402-envelope spec compliance, latency, observed age, on-chain settlement activity, and advertised-price stability. Includes a full component breakdown, machine-readable flags, and an honest observedDays (we report only the history we actually have, with dataCompleteSince marking our gap-free on-chain coverage). Uncataloged endpoints are live-probed on your first query and auto-adopted into the monitored catalog (first-contact score with low confidence -- history accumulates from there). Each paid call also refreshes the endpoint's free public snapshot (page, badge, card), so a fresh score shows everywhere immediately. Know bef

ERC-8004 Inspector agent lookup (identity + reputation) — per call

Buyers need confidence that wallet, agent card, domain label, MCP server, seller profile, and x402 receiver belong together.

x402dir facilitator recommender: pick the best x402 payment facilitator by chain, token, and monthly volume. Returns ranked facilitators with fee estimates (JSON).

x402engine — Anthropic's flagship model with 1M context for coding, analysis, and autonomous work

x402engine — Meta's open-source model — great general-purpose performance at very low cost

x402engine — Google's low-cost multimodal model for high-volume agent workloads

x402engine — Alibaba's flagship open model — excellent multilingual and coding capabilities

x402engine — Generate text embeddings using OpenAI text-embedding-3-small — for semantic search, clustering, RAG

x402engine — Fast, affordable GPT-4o variant — great for simple tasks and high-volume use

x402engine — OpenAI's balanced GPT-5.6 tier for advanced reasoning and agent workflows

x402engine — Google's next-gen flash model — fast and efficient for everyday tasks with improved quality

x402engine — Alibaba's latest model — 1M context, strong multilingual and coding capabilities

x402engine — DeepSeek V3.2 served on the Speciale compatibility route — strong reasoning and coding at low cost

x402engine — OpenAI's efficient GPT-5.6 tier with a 1M-token context window

x402engine — Mistral's code-focused model — optimized for software development and technical tasks

x402engine — MiMo-V2.6-Pro is the flagship foundation model developed by Xiaomi. Built at a scale of over 1T parameters, it is designed to push the ceiling of capability for the most demanding...

x402engine — OpenAI's SOTA agentic coding model — best-in-class for software engineering and code generation

x402engine — Mistral Large 4 is a frontier multimodal (text and image input) model from Mistral AI built for reasoning, coding, and agentic workloads. It offers a 512K-token context window with up...

x402engine — OpenAI's latest small reasoning model — fast chain-of-thought for math, coding, and analysis

x402engine — Alibaba's cost-effective Qwen 3.7 model — 1M context with strong coding and multilingual support

x402engine — Generate a 5-second 768P landscape video with native audio using MiniMax H3

x402engine — xAI's current Grok 4 route — strong reasoning and real-time knowledge

x402engine — Cohere's flagship model — 256k context, strong for enterprise RAG and structured generation

x402engine — Animate a public image into a 5-second video with Kling V3 Pro

x402engine — OpenAI's maximum-compute GPT-5.6 tier for the hardest agent tasks

x402engine — Anthropic's previous-gen Opus — strong reasoning and creative writing, large context window

x402engine — DeepSeek's reasoning model — chain-of-thought reasoning competitive with o3 at fraction of cost

x402engine — Real-time DEX-derived token prices with OHLC data — up to 200 tokens per request