--- title: Methods description: Reference for all Flagship binding evaluation methods, including typed value and details methods for booleans, strings, numbers, and objects. image: https://developers.cloudflare.com/dev-products-preview.png --- > Documentation Index > Fetch the complete documentation index at: https://developers.cloudflare.com/flagship/llms.txt > Use this file to discover all available pages before exploring further. [Skip to content](#%5Ftop) # Methods The Flagship binding provides the following methods for evaluating feature flags. All methods are asynchronous and return a `Promise`. For known evaluation failures, typed methods return the `defaultValue` you provide. Refer to the [types reference](https://developers.cloudflare.com/flagship/binding/types/) for the definitions of `FlagshipEvaluationContext` and `FlagshipEvaluationDetails`. ## `get()` Returns the raw flag value without type checking. Use this method when the flag type is not known at compile time. If you provide `defaultValue`, `get()` returns that value for known evaluation failures, such as a missing flag. If you omit `defaultValue`, known evaluation failures are thrown. TypeScript ``` get(flagKey: string, defaultValue?: unknown, context?: FlagshipEvaluationContext): Promise ``` | Parameter | Type | Required | Description | | ------------ | ------------------------- | -------- | ------------------------------------------------------------------------- | | flagKey | string | Yes | The key of the flag to evaluate. | | defaultValue | unknown | No | The fallback value returned if evaluation fails or the flag is not found. | | context | FlagshipEvaluationContext | No | Key-value attributes for targeting rules. | TypeScript ``` const value = await env.FLAGS.get("checkout-flow", "v1", { userId: "user-42",}); ``` ## `getBooleanValue()` Returns the flag value as a `boolean`. TypeScript ``` getBooleanValue(flagKey: string, defaultValue: boolean, context?: FlagshipEvaluationContext): Promise ``` | Parameter | Type | Required | Description | | ------------ | ------------------------- | -------- | ------------------------------------------------------------------------- | | flagKey | string | Yes | The key of the flag to evaluate. | | defaultValue | boolean | Yes | The fallback value returned if evaluation fails or the flag is not found. | | context | FlagshipEvaluationContext | No | Key-value attributes for targeting rules. | TypeScript ``` const enabled = await env.FLAGS.getBooleanValue("dark-mode", false, { userId: "user-42",}); ``` ## `getStringValue()` Returns the flag value as a `string`. TypeScript ``` getStringValue(flagKey: string, defaultValue: string, context?: FlagshipEvaluationContext): Promise ``` | Parameter | Type | Required | Description | | ------------ | ------------------------- | -------- | ------------------------------------------------------------------------- | | flagKey | string | Yes | The key of the flag to evaluate. | | defaultValue | string | Yes | The fallback value returned if evaluation fails or the flag is not found. | | context | FlagshipEvaluationContext | No | Key-value attributes for targeting rules. | TypeScript ``` const variant = await env.FLAGS.getStringValue("checkout-flow", "v1", { userId: "user-42", country: "US",}); ``` ## `getNumberValue()` Returns the flag value as a `number`. TypeScript ``` getNumberValue(flagKey: string, defaultValue: number, context?: FlagshipEvaluationContext): Promise ``` | Parameter | Type | Required | Description | | ------------ | ------------------------- | -------- | ------------------------------------------------------------------------- | | flagKey | string | Yes | The key of the flag to evaluate. | | defaultValue | number | Yes | The fallback value returned if evaluation fails or the flag is not found. | | context | FlagshipEvaluationContext | No | Key-value attributes for targeting rules. | TypeScript ``` const maxRetries = await env.FLAGS.getNumberValue("max-retries", 3, { plan: "enterprise",}); ``` ## `getObjectValue()` Returns the flag value as a typed object. Use the generic parameter `T` to specify the expected shape. TypeScript ``` getObjectValue(flagKey: string, defaultValue: T, context?: FlagshipEvaluationContext): Promise ``` | Parameter | Type | Required | Description | | ------------ | ------------------------- | -------- | ------------------------------------------------------------------------- | | flagKey | string | Yes | The key of the flag to evaluate. | | defaultValue | T | Yes | The fallback value returned if evaluation fails or the flag is not found. | | context | FlagshipEvaluationContext | No | Key-value attributes for targeting rules. | TypeScript ``` interface ThemeConfig { primaryColor: string; fontSize: number;} const theme = await env.FLAGS.getObjectValue( "theme-config", { primaryColor: "#000", fontSize: 14 }, { userId: "user-42" },); ``` ## `getBooleanDetails()` Returns the flag value as a `boolean` with evaluation metadata. TypeScript ``` getBooleanDetails(flagKey: string, defaultValue: boolean, context?: FlagshipEvaluationContext): Promise> ``` | Parameter | Type | Required | Description | | ------------ | ------------------------- | -------- | ------------------------------------------------------------------------- | | flagKey | string | Yes | The key of the flag to evaluate. | | defaultValue | boolean | Yes | The fallback value returned if evaluation fails or the flag is not found. | | context | FlagshipEvaluationContext | No | Key-value attributes for targeting rules. | TypeScript ``` const details = await env.FLAGS.getBooleanDetails("dark-mode", false, { userId: "user-42",});console.log(details.value); // trueconsole.log(details.reason); // "TARGETING_MATCH" ``` ## `getStringDetails()` Returns the flag value as a `string` with evaluation metadata. TypeScript ``` getStringDetails(flagKey: string, defaultValue: string, context?: FlagshipEvaluationContext): Promise> ``` | Parameter | Type | Required | Description | | ------------ | ------------------------- | -------- | ------------------------------------------------------------------------- | | flagKey | string | Yes | The key of the flag to evaluate. | | defaultValue | string | Yes | The fallback value returned if evaluation fails or the flag is not found. | | context | FlagshipEvaluationContext | No | Key-value attributes for targeting rules. | TypeScript ``` const details = await env.FLAGS.getStringDetails("checkout-flow", "v1", { userId: "user-42",});console.log(details.value); // "v2"console.log(details.variant); // "new"console.log(details.reason); // "TARGETING_MATCH" ``` ## `getNumberDetails()` Returns the flag value as a `number` with evaluation metadata. TypeScript ``` getNumberDetails(flagKey: string, defaultValue: number, context?: FlagshipEvaluationContext): Promise> ``` | Parameter | Type | Required | Description | | ------------ | ------------------------- | -------- | ------------------------------------------------------------------------- | | flagKey | string | Yes | The key of the flag to evaluate. | | defaultValue | number | Yes | The fallback value returned if evaluation fails or the flag is not found. | | context | FlagshipEvaluationContext | No | Key-value attributes for targeting rules. | TypeScript ``` const details = await env.FLAGS.getNumberDetails("max-retries", 3, { plan: "enterprise",});console.log(details.value); // 5console.log(details.reason); // "TARGETING_MATCH" ``` ## `getObjectDetails()` Returns the flag value as a typed object with evaluation metadata. Use the generic parameter `T` to specify the expected shape. TypeScript ``` getObjectDetails(flagKey: string, defaultValue: T, context?: FlagshipEvaluationContext): Promise> ``` | Parameter | Type | Required | Description | | ------------ | ------------------------- | -------- | ------------------------------------------------------------------------- | | flagKey | string | Yes | The key of the flag to evaluate. | | defaultValue | T | Yes | The fallback value returned if evaluation fails or the flag is not found. | | context | FlagshipEvaluationContext | No | Key-value attributes for targeting rules. | TypeScript ``` interface ThemeConfig { primaryColor: string; fontSize: number;} const details = await env.FLAGS.getObjectDetails( "theme-config", { primaryColor: "#000", fontSize: 14 }, { userId: "user-42" },);console.log(details.value); // { primaryColor: "#0051FF", fontSize: 16 }console.log(details.variant); // "brand-refresh" ``` ## Error handling Typed evaluation methods return the `defaultValue` you provided for known evaluation failures, such as a missing flag or type mismatch. Unexpected runtime failures can still throw. Use the `*Details` methods to inspect known evaluation failures. ### Type mismatch If you call a typed method on a flag with a different type (for example, `getBooleanValue` on a string flag), the method returns the default value. The `*Details` methods set `errorCode` to `"TYPE_MISMATCH"`. TypeScript ``` // Flag "checkout-flow" is a string flag, but you call getBooleanDetails.const details = await env.FLAGS.getBooleanDetails("checkout-flow", false);console.log(details.value); // false (the default value)console.log(details.errorCode); // "TYPE_MISMATCH" ``` ### Evaluation failure If evaluation fails for another reason, the method returns the default value. The `*Details` methods include an `errorCode` such as `"FLAG_NOT_FOUND"`, `"INVALID_CONTEXT"`, `"PARSE_ERROR"`, or `"GENERAL"`. TypeScript ``` const details = await env.FLAGS.getStringDetails( "nonexistent-flag", "fallback",);console.log(details.value); // "fallback"console.log(details.errorCode); // "FLAG_NOT_FOUND" ``` ## Parameters reference The following table summarizes the parameters shared across all evaluation methods. | Parameter | Type | Required | Description | | ------------ | ------------------------- | ---------------- | --------------------------------------------------------------------------------------------- | | flagKey | string | Yes | The key of the flag to evaluate. | | defaultValue | varies | Yes (except get) | The fallback value returned if evaluation fails or the flag is not found. | | context | FlagshipEvaluationContext | No | Key-value attributes for targeting rules (for example, { userId: "user-42", country: "US" }). | ```json {"@context":"https://schema.org","@type":"TechArticle","@id":"https://developers.cloudflare.com/flagship/binding/methods/#page","headline":"Methods ยท Cloudflare Flagship docs","description":"Reference for all Flagship binding evaluation methods, including typed value and details methods for booleans, strings, numbers, and objects.","url":"https://developers.cloudflare.com/flagship/binding/methods/","inLanguage":"en","image":"https://developers.cloudflare.com/dev-products-preview.png","dateModified":"2026-06-24","publisher":{"@type":"Organization","name":"Cloudflare","url":"https://www.cloudflare.com/"},"isPartOf":{"@type":"WebSite","@id":"https://developers.cloudflare.com/#website","name":"Cloudflare Docs","url":"https://developers.cloudflare.com/"}} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/directory/","name":"Directory"}},{"@type":"ListItem","position":2,"item":{"@id":"/flagship/","name":"Flagship"}},{"@type":"ListItem","position":3,"item":{"@id":"/flagship/binding/","name":"Binding API"}},{"@type":"ListItem","position":4,"item":{"@id":"/flagship/binding/methods/","name":"Methods"}}]} ```