How much does Massive charge AI agents per request over x402?

Each of the 23 routes on agent.massive.com was listed at $0.01 per request on 2026-10-11, paid in USDC on Base. The 402 response for the aggregates route showed an amount of 10000 in 6-decimal units, which is $0.01. Only successful requests are charged, and each page of a paginated result is a separate request.

Does the Massive MCP server need an API key?

Not the hosted one. You add https://mcp.massive.com/ to your MCP client and sign in over OAuth; access follows your Massive plan, and a free Basic account can connect. The self-hosted mcp_massive server uses an API key.

What data is not available through x402?

Tick data, streaming and every asset class other than US stocks. Aggregates and indicators are end-of-day, snapshots cover the current session, and intraday values are based on Massive's fair-market-value model. Real-time trades and quotes need an API key and a plan.

When is a Massive plan cheaper than x402?

At about 2,900 requests a month against Stocks Starter ($29) and 19,900 against Stocks Advanced ($199). Requesting daily bars for 500 tickers one by one each evening makes roughly 10,500 requests a month, about $105, but the whole-market daily route returns all tickers for a session in one request, so the cheapest design depends on the routes the agent uses.

Massive for AI Agents 2026: MCP Server vs x402 Pay-Per-Request

Education, not investment advice. Past performance does not predict future results. How we check our numbers.

Massive (formerly Polygon.io) gives an AI agent three ways in: a hosted MCP server at mcp.massive.com that signs in over OAuth and follows your plan, per-request purchases on agent.massive.com paid in USDC over the x402 protocol with no account at all, and the ordinary API key for REST and WebSockets. The x402 routes cost $0.01 per request each and cover US stocks only, with end-of-day bars and current-session snapshots. All of this was read from Massive's docs, its announcements and the routes' own payment responses on 2026-10-11¹²³. Choose by who owns the account and how often the agent calls.

What are the three access paths?

	Hosted MCP server	x402 pay-per-request	API key (REST / WebSocket)
Host	`https://mcp.massive.com/`	`agent.massive.com`	`api.massive.com`, `socket.massive.com`
Account needed	Yes (free Basic works)	No	Yes
Credential	OAuth sign-in	Wallet with USDC on Base	API key
Billing	Your plan	$0.01 per request, per route	Your plan
Data	Whatever your plan includes	US stocks; FMV-based intraday values	Every asset class in your plan
Recency	Per plan	End-of-day bars; current-session snapshots	Up to real-time
Streaming	No	No	Yes, WebSocket

Sources: Massive's x402 docs and AI-tools quickstart, and the 402 responses of the routes themselves¹²³.

How does the hosted MCP server work?

You add https://mcp.massive.com/ to an MCP client, sign in through the browser, and the model can then search Massive's endpoints and call them; there is nothing to install and no key in a config file⁴. Massive lists setup guides for Claude Code, Claude Desktop, Cursor, ChatGPT, Grok, Codex, GitHub Copilot and the Gemini CLI². Access mirrors your entitlements: requesting an asset class your plan lacks returns an access-denied error, and a free Basic account is enough to connect²⁴. A self-hosted version (mcp_massive, MIT-licensed) adds a local DataFrame and SQL workspace for heavier analysis²⁵.

How does x402 pay-per-request work?

x402 uses the HTTP 402 Payment Required status to price a resource inside the response. The agent requests a route, receives machine-readable payment requirements, signs a USDC payment, and retries with proof; Coinbase Developer Platform's facilitator verifies and settles it before Massive returns the data¹. The 402 response from /v2/aggs/ticker/{ticker}/range/... on 2026-10-11 named the scheme exact, network eip155:8453 (Base), asset USD Coin, amount 10000 in 6-decimal units ($0.01) and a 60-second payment timeout³.

Massive's docs add three billing rules: only successful requests are charged, a rejected or failed request costs nothing, and each page of a paginated result is charged separately¹. Route prices can differ, so an agent should read the amount from each 402 response rather than assume a flat rate¹.

What data can an agent buy over x402?

Twenty-three routes on 2026-10-11, all listed at $0.01 per request on Agentic Market⁶: aggregate bars (one ticker over a range, one day for one ticker, one day for the whole market), snapshots (one ticker, all tickers, top gainers and losers), SMA, EMA, RSI and MACD, ticker search and details, news, and SEC filings (EDGAR index, 10-K sections, 8-K text and classified disclosures, risk factors, 13F holdings, Forms 3 and 4)¹⁶.

The limits matter. Aggregates and indicators are end-of-day, with the newest bar the last completed session; snapshots cover the current session and reset at 3:30 AM ET; intraday values are based on Massive's fair-market-value (FMV) model, not the consolidated tape; and tick data, streaming and other asset classes are not available over x402¹. A free POST https://agent.massive.com/feedback endpoint takes requests for missing routes¹.

When is $0.01 a request cheaper than a plan?

Plain arithmetic: Stocks Starter at $29/month equals 2,900 x402 requests, and Stocks Advanced at $199/month equals 19,900 requests⁷. An agent that answers a few questions a day, each needing a handful of calls, stays far below either. A research loop that requests daily bars for 500 tickers one by one every evening makes about 10,500 requests in a 21-session month, or $105, more than Starter, which also adds unlimited calls, 5 years of history and flat files. Route design changes the answer: the whole-market daily route returns every ticker for a session in one request, so the same evening pull costs about $0.01 a day plus any extra pages¹⁶.

The comparison is not like for like. Starter's data is 15-minute-delayed SIP aggregates; x402 intraday values are FMV-based and its bars are end-of-day. x402's advantage is that no human creates an account or stores a key.

Which path should I use?

An agent working inside your own account: the hosted MCP server. It reuses your plan, needs no key in config, and Massive recommends it as the starting point².
An autonomous agent that must buy data mid-task without onboarding: x402, with a wallet spending limit and caching so repeated questions do not re-pay.
Streaming, real-time quotes, options, futures or bulk history: an API key with WebSockets or flat files; neither MCP nor x402 streams¹.

Whichever path you choose, treat tool output as untrusted data in the agent's context; Finance MCP Security Baseline covers the controls, and the Finance MCP Directory grades the servers.

Connects to

Polygon.io Pricing 2026: the plans the MCP server and API key follow.
Polygon.io to Massive Migration 2026: hosts and SDKs after the rebrand.
MCP vs Function Calling for Finance: when an MCP server beats a hand-written tool.
Agent Cost Envelope Calculator: budget the model side of the same agent.

References

Massive. "x402 Payments" (no account; USDC on Base; data available; end-of-day aggregates, session snapshots, FMV intraday values; only successful requests charged; pagination billed per page; free feedback endpoint; comparison with API keys). Read 2026-10-11. https://massive.com/docs/ai-tools/x402 ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰
Massive. "AI Tools Quickstart" (hosted MCP server at https://mcp.massive.com/ over OAuth; supported clients; access mirrors entitlements; self-hosted option). Read 2026-10-11. https://massive.com/docs/ai-tools/quickstart ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶
agent.massive.com. HTTP 402 payment-required response for GET /v2/aggs/ticker/AAPL/range/1/day/2026-08-03/2026-08-07 (x402Version 2; scheme exact; network eip155:8453; asset USD Coin; amount 10000; maxTimeoutSeconds 60). Read 2026-10-11. https://agent.massive.com/ ↩ ↩² ↩³
Massive. "Give Your AI Live Market Data with Massive" (hosted MCP server, OAuth, no install; free Basic account can connect). September 15, 2026. https://massive.com/blog/give-your-ai-live-market-data-with-massive ↩ ↩²
GitHub. "massive-com/mcp_massive" (MIT license). Read 2026-10-11. https://github.com/massive-com/mcp_massive ↩
Agentic Market. "Massive x402 service" (23 endpoints on agent.massive.com, $0.01 per request each). Read 2026-10-11. https://agentic.market/services/agent-massive-com ↩ ↩² ↩³
Massive. "Pricing" (Stocks Starter $29/month, Advanced $199/month). Read 2026-10-11. https://massive.com/pricing ↩

Frequently asked questions

How much does Massive charge AI agents per request over x402?: Each of the 23 routes on agent.massive.com was listed at $0.01 per request on 2026-10-11, paid in USDC on Base. The 402 response for the aggregates route showed an amount of 10000 in 6-decimal units, which is $0.01. Only successful requests are charged, and each page of a paginated result is a separate request.
Does the Massive MCP server need an API key?: Not the hosted one. You add https://mcp.massive.com/ to your MCP client and sign in over OAuth; access follows your Massive plan, and a free Basic account can connect. The self-hosted mcp_massive server uses an API key.
What data is not available through x402?: Tick data, streaming and every asset class other than US stocks. Aggregates and indicators are end-of-day, snapshots cover the current session, and intraday values are based on Massive's fair-market-value model. Real-time trades and quotes need an API key and a plan.
When is a Massive plan cheaper than x402?: At about 2,900 requests a month against Stocks Starter ($29) and 19,900 against Stocks Advanced ($199). Requesting daily bars for 500 tickers one by one each evening makes roughly 10,500 requests a month, about $105, but the whole-market daily route returns all tickers for a session in one request, so the cheapest design depends on the routes the agent uses.