Start here: often you don’t need us
Your code assistant is good at this. Point it at an OpenAPI spec and it will write you a working client, usually on the first try. For one API, with you reading the diff, that is the right tool. Use it. This page is about the second API. And the one that spends money.1. It writes the call it can read
A code assistant works from what is written down. That is its whole method. So it cannot know what is missing. And on the surfaces that matter, a lot is missing — not because someone was careless, but because the fact does not belong in a document at all.
Those 16 extra Jupiter accounts are the legs of whichever route the aggregator picked a
second earlier. They are not in the specification and cannot be — they are not facts
about the program.
Given that surface, an assistant writes confident, well-formed, wrong code. Nothing in
its input tells it so.
2. Its debugging loop needs an error
Write, run, read the error, fix. That loop is exactly why a code assistant is good. It has two limits. On a paid API, every turn of the loop is billed. On a transaction that spends, the loop does not exist — the first attempt is the real one.And the failure that costs the most produces no error at all. The call is well-formed,
the API accepts it, nothing throws — the wrong pool, the wrong account, a charge posted.
The loop terminates successfully, on a wrong outcome.
3. It pays for the surface on every task
A 43-operation API is a lot of tokens. Reading it competes with the actual task, in the same context window, every time. Gecko hands over the one call instead. On a real production API that measured 79.3% less context (113,072 B of OpenAPI → 23,382 B of agent surface, 43 operations, measured 2026-08-06) — with first-call-correctness held, which is the only version of that number worth quoting.4. Its natural output puts your key in a file
Ask an assistant to wire up an API and you get a credential in.env or mcp.json —
inside the agent’s context, in your shell history, in your repo if you blink.
Gecko injects credentials at call time. The agent describes intent. It never sees a key.
The difference in one line
A code assistant gives you integration code — an artifact you now own and maintain, correct on the day it was written. Gecko gives your agent the call — derived fresh, every fact tagged with where it came from, and for anything that spends, simulated to a receipt before it counts. They are not competing. Most teams should have both.See it decide
Watch it route an intent, show what it rejected, and mark every account with its
origin — including the ones it flags instead of guessing.
The receipt
What a simulation proves before you sign, and what it does not.