x402 vs A2A vs ACP

Cerebrus services are available through three protocols. Choose based on your use case.

Comparison

	x402 (Direct API)	A2A (Agent-to-Agent)	ACP (Virtuals Protocol)
Target user	Developers, bots, dashboards, agents	A2A agent networks	Agents on Virtuals Protocol
Payment	USDC micropayments on Base or Solana	None in-band: the reply names the HTTP endpoint and its x402 terms, and you pay there	USDC on Base, in ACP escrow
Authentication	Wallet signature (no API keys)	None: discovery and quotes are free	ACP SDK + agent wallet
Discovery	API docs	Agent Card (`.well-known`)	Virtuals marketplace
Transport	HTTP REST	JSON-RPC 2.0 over HTTP	ACP SDK
Round trips	One HTTP request (plus the 402 on the first try)	One JSON-RPC request, then the HTTP call	Job negotiation and escrow
Pricing	$0.01–$0.06 per call	$0.01–$0.06 per skill (paid over HTTP)	A USDC budget per job (below)
Settlement	Instant (Base L2 or Solana)	Over HTTP (x402), as for direct calls	ACP escrow release
Status	Live	Live (discovery)	Paused
Protocol	HTTP 402 (open standard)	A2A (Linux Foundation)	Agent Commerce Protocol (Virtuals)

Available Services

Via x402

Endpoint	Price	Description
`GET /screener`	$0.06 USDC	Scan 50+ perpetuals: signal strength, RSI zone, trend, volatility, funding bias, confluence
`GET /pulse/{coin}`	$0.025 USDC	Multi-timeframe technical analysis, derivatives snapshot, regime and confluence
`GET /sentiment`	$0.01 USDC	Bucketed market sentiment label and how many sources are live
`GET /funding/{coin}`	$0.01 USDC	Funding rate statistics over a 1-168 hour lookback (hourly rates)
`GET /oi/{coin}`	$0.015 USDC	Open interest: 1h/4h/24h deltas, percentile, trend, price-OI divergence
`GET /spread/{coin}`	$0.015 USDC	Impact spread and uncalibrated slippage estimates at $10k-$500k
`GET /correlation`	$0.05 USDC	BTC-alt correlation of 1h returns (30h, 7d or 30d window) with regime
`GET /basis/{coin}`	$0.02 USDC	Hyperliquid perp premium to its oracle, plus oracle vs Chainlink spot
`GET /depeg`	$0.01 USDC	USDC peg status from the Chainlink oracle on Arbitrum
`GET /arb`	$0.02 USDC	Market Stress Index from cross-chain arbitrage scans
`GET /cex-dex/{token}`	$0.02 USDC	Coinbase vs DEX/Chainlink price divergence for one token
`GET /liquidations/{coin}`	$0.03 USDC	Modelled liquidation zones by leverage tier, with cascade risk
`GET /bundle/{coin}`	$0.05 USDC	/pulse output plus 24h funding statistics and sentiment in one call
`GET /demo/{coin}`	Free	Full /pulse analysis (1h, 4h) for BTC and ETH, cached 60 s, 3 requests/min, no wallet
`GET /health`	Free	Gateway health status
`GET /coins`	Free	List the supported perpetuals

Via A2A

Skill ID	Served by	Price (USDC)	Needs a coin	Description
`confluence-analysis`	`GET /pulse/{coin}`	$0.025	Yes	Multi-timeframe technical analysis with the confluence vote share
`market-screener`	`GET /screener`	$0.06	No	Screen 50+ perpetuals by signal strength
`open-interest-analysis`	`GET /oi/{coin}`	$0.015	Yes	OI deltas, percentile, trend and price-OI divergence
`spread-analysis`	`GET /spread/{coin}`	$0.015	Yes	Impact spread and slippage estimates
`correlation-matrix`	`GET /correlation`	$0.05	No	BTC-alt correlation matrix with regime
`intelligence-bundle`	`GET /bundle/{coin}`	$0.05	Yes	Pulse, 24h funding and sentiment in one call
`basis-analysis`	`GET /basis/{coin}`	$0.02	Yes	Perp premium to the Hyperliquid oracle, and oracle vs Chainlink
`cex-dex-divergence`	`GET /cex-dex/{token}`	$0.02	Yes	Coinbase vs DEX/Chainlink divergence for one token
`collateral-health`	`GET /depeg`	$0.01	No	USDC peg status from Chainlink
`liquidation-heatmap`	`GET /liquidations/{coin}`	$0.03	Yes	Modelled liquidation zones with cascade risk
`market-stress`	`GET /arb`	$0.02	No	Cross-chain arbitrage stress index

Via ACP (paused)

Each offering delivers the engine’s JSON for one coin; none calls a model.

Offering	Delivers	Budget (USDC)
`cerebrus_lite`	the /pulse output (1h, 4h)	$0.25
`cerebrus_synthesis`	the /bundle output (1h, 4h)	$0.75
`cerebrus_premium`	the /bundle output (15m, 1h, 4h, 1d)	$2.50
`pulse`	the /pulse output (1h, 4h)	$0.03

When to Use x402

You’re building a dashboard or monitoring tool that needs frequent data pulls
You want the lowest latency and lowest cost per query
You’re writing a bot or script that consumes structured data
You want to avoid the Virtuals ecosystem and use standard HTTP
You need high-frequency queries (up to 2,000 a day per IP)

When to Use A2A

You’re building an AI agent that needs to discover and consume services programmatically
You want standardized agent discovery via the Agent Card protocol
You want to ask for a skill in plain language over JSON-RPC (message/send) and be told where to get it
You want to integrate with the A2A ecosystem (a Linux Foundation project)
Your agent can then pay the named HTTP endpoint with an x402 v2 client

When to Use ACP

Your agent runs on Virtuals Protocol and buys services through ACP jobs and escrow
You want the /pulse or /bundle output for one coin as an ACP deliverable
Note: the ACP seller is paused while it moves to ACP v2; use x402 meanwhile

Can I Use Multiple?

Yes. Many teams combine protocols:

x402 /pulse/BTC → Get live technical indicators ($0.025)
A2A message/send → Agent discovers a skill and gets the HTTP endpoint and x402 terms that serve it
ACP cerebrus_synthesis → The /bundle output for one coin, as an ACP job (when ACP is back)

A2A adds discovery on top of x402: it names the endpoint and its terms, and the payment is the same x402 call on Base or Solana. ACP sells the same engine data as ACP jobs.

Migration

Moving between protocols doesn’t require account changes. A2A leads to the same wallet-based x402 payments on Base or Solana as direct calls. ACP uses USDC on Base through Virtuals Protocol escrow. There’s no lock-in to any protocol.