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@jsvision/core / assertEssentials

Function: assertEssentials() ​

assertEssentials(caps, facts, options?): EssentialsReport

Defined in: safety/essentials.ts:139

Assert the essentials before starting: throws EssentialsNotMetError when the terminal is unusable, otherwise returns the report. Use this as the gate right before you create and start the host.

If you pass a logger, each degradation is written once at info level (a screen-safe notice — never to the terminal). This function does not touch or restore the terminal itself.

Parameters ​

caps ​

CapabilityProfile

Resolved capability profile.

facts ​

HostFacts

TTY facts from detectTty(); do not pass an un-started Host.

options? ​

Optional { logger } to emit the one-time degradation notices.

logger? ​

Logger

Returns ​

EssentialsReport

The EssentialsReport (including any degradations) when essentials are met.

Throws ​

EssentialsNotMetError when the terminal lacks an essential capability.

Example ​

ts
import { assertEssentials, resolveCapabilities, detectTty, createHost } from '@jsvision/core';

const caps = resolveCapabilities().profile;
assertEssentials(caps, { isTTY: detectTty() }); // throws on a non-TTY
const host = createHost({ caps });
await host.start();