The user wants me to rewrite a headline about TypeScript's `satisfies` operator.

Short summary

TypeScript's satisfies operator (4.9+) preserves literal type inference while enforcing contracts—unlike annotations that widen types. Essential for configuration objects, discriminated unions, const assertions, and API validation where exact types enable compile-time exhaustiveness checking and prevent runtime errors. Demonstrates practical patterns for feature flags, payment methods, route configs, and response validation.

• •satisfies preserves literal types while type annotations widen them, losing specificity
• •Critical for discriminated unions, immutable configs, and exhaustiveness checking
• •Enables compile-time guarantees that eliminate entire classes of runtime errors

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