What it means here## Static typing in this material In the channel's material, static typing appears as the mechanism that makes code execution safe for agents. When a model runs TypeScript against an API's SDK instead of calling MCP tools one by one, the whole approach only works if the library behaves perfectly out of the box — the right version, no hallucinated methods. Static typing is the safety net: a type checker catches errors in real time — stripe.transactions.list doesn't exist; did you mean payment intents, orders, or balance transactions? — returning relevant documentation inline, powered by a sub-agent unburdened by the full conversation context. [^913c216d-5ccb-51d9-8f42-8feb7c017d9d@2398] [^ea9761fa-0184-555e-be30-4928a6682680@2412] [moment: 2398] [moment: 2412] Why it matters### The hallucination guard Without typed SDKs, a code-executing agent could happily invent methods that don't exist. The type checker surfaces the mistake immediately and points toward the correct API surface, so the model self-corrects instead of failing silently. This is what lets Stainless run agent code in network-locked sandboxes — one API provider per sandbox, so only api.stripe.com is reachable — with type checking catching hallucinated calls. [^913c216d-5ccb-51d9-8f42-8feb7c017d9d@2611] [^ea9761fa-0184-555e-be30-4928a6682680@2638] - Static typing is presented as the enabler for agent code execution: the type checker guarantees the SDK the model is calling actually exists and behaves as intended. - It catches hallucinated method calls in real time and returns relevant documentation inline via a sub-agent, keeping the main context lean. [^913c216d-5ccb-51d9-8f42-8feb7c017d9d@2398] - It is one half of the code-execution stack — typed SDKs in network-locked sandboxes — that Stainless offers as an alternative to exposing hundreds of MCP tools. [^913c216d-5ccb-51d9-8f42-8feb7c017d9d@2398]: Anthropic Just Bought a Dev Tools Startup for $300M. Here's What Its Founder Told Me. — Alex Rattray on static typing as the hallucination guard, from 2398s. [^ea9761fa-0184-555e-be30-4928a6682680@2412]: Alex Rattray, MCP conversation — type checker returning relevant docs inline, from 2412s. [^913c216d-5ccb-51d9-8f42-8feb7c017d9d@2611]: Anthropic Just Bought a Dev Tools Startup for $300M. Here's What Its Founder Told Me. — sandboxing, from 2611s. [^ea9761fa-0184-555e-be30-4928a6682680@2638]: Alex Rattray, MCP conversation — network-locked sandbox, from 2638s.