CoinMarketCap API for AI Agents: MCP, Keyless Data and Sources

How the Two APIs Compare for Agent Work

Read from each provider's own pricing pages and documentation. Figures verified 8 September 2026. Both pricing pages quote a monthly price that assumes annual billing, so prices here are compared annual to annual. Read live 14 September 2026.

Calling the Data Without an Account

The keyless public API takes GET requests at https://pro-api.coinmarketcap.com/public-api with no authentication header at all. For an agent, that removes the step no agent can complete on its own: a human signing up, generating a key, and pasting it into a config file.

curl "https://pro-api.coinmarketcap.com/public-api/v1/simple/price?ids=1,1027&convert=USD"

Thirty-six endpoints are reachable this way, split 19 Standard and 17 DEX. The Standard set covers quotes, listings, coin info, the ID map, categories, global metrics, price conversion and the index endpoints. The DEX set covers spot pairs, token prices, liquidity, pools, holders, security detail and candles.

Keyless requests share an IP-based rate pool, so a 429 response is a signal to back off with exponential retry rather than a hard stop. A free API key raises the ceiling to 15,000 monthly credits at 50 requests per minute on the Basic plan, and that free tier carries a commercial licence.

CoinGecko's free Demo plan carries 10,000 monthly credits at 100 calls per minute, and it requires an API key. Commercial use is not permitted on that tier, and attribution to CoinGecko is required.

The Paths an Agent Can Take

Six paths reach the same underlying data, and the right one depends on what is holding the agent.

The MCP server is the shortest route into an MCP-compatible client. It runs at https://mcp.coinmarketcap.com/mcp and authenticates with an X-CMC-MCP-API-KEY header, and it exposes 12 tools grouped into market data (search, live quotes, global metrics), technical analysis (crypto and market cap), information and news (crypto info, latest news, concept search, trending narratives), and advanced metrics (on-chain, derivatives, macro events). The on-chain tools are documented as work in progress, with multi-market DEX trading and wider chain coverage planned.

x402 is the path for an agent with a wallet and no account. Payment on Base authenticates each call at $0.01, so there is no key to provision and no billing relationship to set up first. That suits a short-lived or single-purpose agent better than a subscription does.

Skills package multi-step workflows over whichever path is already configured, and crypto research is the one to start with for retrieval work. There is a machine-readable index of the whole surface at https://pro.coinmarketcap.com/llms.txt.

CoinGecko's API offers the same four agent paths: an MCP server, a Skill, a CLI and x402 endpoints.

Index Data an Agent Cannot Compute From Prices

Four proprietary indices are exposed as endpoints, each with a latest and a historical variant:

• Fear and Greed/v3/fear-and-greed/latest/v3/fear-and-greed/historical
• CMC100/v3/index/cmc100-latest/v3/index/cmc100-historical
• CMC20/v3/index/cmc20-latest/v3/index/cmc20-historical
• Altcoin Season/v1/altcoin-season-index/latest/v1/altcoin-season-index/historical

All eight are keyless. For an agent answering a question like "is the market fearful right now", that is one call returning a scored value with history behind it, instead of a modelling task the agent has to invent and defend. CoinGecko's complete Pro API endpoint overview lists 97 endpoints and none of them is a market index, a sentiment score or a fear-and-greed reading, so the same question there becomes a computation over raw market data.

Answers With Their Sources Attached

The CMC AI endpoint family is live on the Pro API, documented at /api/documentation/pro-api-reference/cmc-ai, and it returns something different from the rest of the surface: generated answers rather than numbers.

Each item carries a type (a fixed question, a trending question, or a headline), a display title, a two-section markdown answer split into a TLDR and a body, and an array of source URLs. Two fields on the array do the work an agent needs. sources_count reports the true number of sources behind the answer, and sources_truncated says whether the returned list is shorter than that count. So an agent can cite what it was given and state honestly how much it is not showing.

The shape looks like this:

{
  "type": "fixed_question",
  "title": "What are the trending narratives?",
  "question_key": "trending_narratives",
  "answer": { "tldr": "## TLDR ...", "body": "## Deep Dive ..." },
  "sources": [ { "url": "https://coinmarketcap.com/trending-cryptocurrencies/" } ],
  "sources_count": 91,
  "sources_truncated": true,
  "generated_at": "2026-08-17T09:11:37Z"
}

Three details shape how an agent should use it. Source URLs are normalised before the array is deduplicated, so tracking parameters do not produce the same article twice. The content is fetched from a database rather than generated per request, which means a call returns the answer the CoinMarketCap site is already showing. And answers are English only in the first release.

The first release is Enterprise, and the answers are regenerated on a schedule rather than on demand, so an agent polls on a cadence instead of asking for a fresh answer. Historical snapshots are not part of this release.

The full question set and its keys, the coverage map and how to read an empty result, and how every answer is sourced are covered separately. The same content is also already published as pages, which is a faster way to see what an answer actually looks like before writing any code: a coin's latest updates and price prediction pages are the rendered form of two of the question types.

Pricing and Licensing

A commercial licence is attached from the free Basic tier, which carries 15,000 monthly credits at 50 requests per minute, and no attribution obligation is stated on any tier. It is a limited, non-exclusive licence covering one product with up to 100,000 users, and it does not extend to redistributing or reselling the data as a standalone service. CoinGecko's free Demo plan carries no commercial licence and requires attribution, and its commercial licence begins on Basic at $29/mo billed yearly with 100,000 monthly credits. For an agent that renders answers inside someone else's product, an attribution requirement is a design constraint as much as a licensing one.

CoinMarketCap API tiers as published, verified 8 September 2026.

Tier for Tier Against CoinGecko

Both providers quote a monthly price that assumes annual billing, so this compares annual to annual and pairs the plans by what they cost rather than by what they are called. Both pricing pages read 14 September 2026.

At the same $348, CoinMarketCap’s allowance is 50% larger. At the two middle points CoinMarketCap is cheaper for comparable credits and carries the higher rate limit, most clearly at Growth against Lite: the same 2,000,000 credits for $1,202 less a year, with half again the requests per minute. Above that CoinGecko moves to Enterprise while CoinMarketCap still publishes a price.

Three things to check against the build before picking a tier. Update frequency is 60 seconds on Basic and Builder and real-time from Startup up. OHLCV and market-pair endpoints begin at Startup, so an agent that needs candles cannot run on the two lowest tiers. And the keyless path sits outside this table, so a prototype can run before any plan decision is made.

Which One Fits the Build

• A prototype agent with no account and no wallet CoinMarketCap36 REST endpoints answer without a key or a signup, while CoinGecko's free Demo tier requires an API key
• An agent that must cite what it says CoinMarketCapThe CMC AI endpoints return source URLs with a true sources_count alongside each answer, where CoinGecko's /insights documents no source field
• A sentiment or market-regime question CoinMarketCapFear and Greed, CMC100, CMC20 and Altcoin Season are single keyless calls rather than a computation
• A commercial agent on no budget at all CoinMarketCapThe free Basic tier carries a commercial licence and 15,000 monthly credits, while CoinGecko's free Demo plan carries none and requires attribution
• An agent that needs streaming at the lowest monthly price CoinGeckoWebSocket and webhook delivery start on its Basic plan at $29/mo billed yearly, against Startup at $79/mo

FAQ