When an agent connects to NoVo’s MCP server it receives one catalogue. Free tools and paid tools are listed together. Nothing is hidden until you subscribe. So the question is what happens when the agent calls each kind.
What the free tools return
Many tools need no key at all. get_dealer_levels returns the call wall, put wall and spot for SPY, QQQ and IWM. get_volatility_record ranks the VIX family against its own history. get_market_pulse, get_economic_calendar, get_sector_heatmap and get_wire_news cover the backdrop. get_ticker_brief gathers what the free surface holds on one name.
Free does not mean degraded. It means delayed or narrower in scope, and the payload says which. The dealer levels carry a delayed field. Fields held back, such as the gamma flip, are named in a gated field. The principle is in a free tier should be useful, not a teaser.
What a subscription opens
Paid tools need an API subscription and a key. get_equity_map serves the dealer map whole and current. get_crypto_map serves the full crypto book. get_stocks_onchain and get_robinhood_trending cover the weekend perps, stock tokens and the Robinhood Chain trending list. get_base_rates, get_gamma_profile and get_session_history read NoVo’s own logged history.
What the key does
The key is sent with the request and identifies who is asking. The subscription behind it decides what opens. A key on its own does not unlock paid data. That distinction has its own article, your API key says who you are, not what you bought.
How a refusal should read
When an agent calls a paid tool without a subscription, the tool answers saying exactly that. It does not return a sample, a truncated list or a block of zeros. This matters more for an agent than for a person. A person sees a paywall and understands it. A model that receives a thin sample will summarize it as if it were the market.
A good agent passes the refusal on in plain words: this reading needs the paid API, and here is what the free tool can tell you instead. A poor one fills the gap from memory. If yours does the second, tell it that a refused tool means no answer.
Gated is not missing
The same care applies inside a free response. A field named in gated is withheld. It is not zero and it is not absent from the market. An agent that reports there is no gamma flip today has misread the payload. The honest sentence is that the flip is on the paid map.
Choosing between them
Run the free tools through your agent for a week before paying for anything. You will learn whether the freshness fields, the refusals and the errors behave. Those do not change when you subscribe. What changes is delay and depth. Plans and what each opens are listed on the MCP & API page.