diff --git a/packages/vitest/src/integrations/inject.ts b/packages/vitest/src/integrations/inject.ts
index 57cc9cafde6b..1abdf0633e59 100644
--- a/packages/vitest/src/integrations/inject.ts
+++ b/packages/vitest/src/integrations/inject.ts
@@ -5,9 +5,9 @@ import { getWorkerState } from '../utils/global'
  * Gives access to injected context provided from the main thread.
  * This usually returns a value provided by `globalSetup` or an external library.
  */
-export function inject<T extends keyof ProvidedContext>(
+export function inject<T extends keyof ProvidedContext & string>(
   key: T,
 ): ProvidedContext[T] {
   const workerState = getWorkerState()
-  return workerState.providedContext[key]
+  return workerState.providedContext[key] as ProvidedContext[T]
 }
diff --git a/packages/vitest/src/node/core.ts b/packages/vitest/src/node/core.ts
index dfad23e65356..d0ed0afeeef5 100644
--- a/packages/vitest/src/node/core.ts
+++ b/packages/vitest/src/node/core.ts
@@ -183,7 +183,7 @@ export class Vitest {
     }
   }
 
-  public provide<T extends keyof ProvidedContext>(key: T, value: ProvidedContext[T]) {
+  public provide<T extends keyof ProvidedContext & string>(key: T, value: ProvidedContext[T]) {
     this.getCoreWorkspaceProject().provide(key, value)
   }
 
diff --git a/packages/vitest/src/node/globalSetup.ts b/packages/vitest/src/node/globalSetup.ts
index 69ddb38402ed..310c8949770a 100644
--- a/packages/vitest/src/node/globalSetup.ts
+++ b/packages/vitest/src/node/globalSetup.ts
@@ -5,7 +5,7 @@ import type { ResolvedConfig } from '../types/config'
 
 export interface GlobalSetupContext {
   config: ResolvedConfig
-  provide: <T extends keyof ProvidedContext>(
+  provide: <T extends keyof ProvidedContext & string>(
     key: T,
     value: ProvidedContext[T]
   ) => void
diff --git a/packages/vitest/src/node/workspace.ts b/packages/vitest/src/node/workspace.ts
index 85a0386790f6..e2f5b8002f68 100644
--- a/packages/vitest/src/node/workspace.ts
+++ b/packages/vitest/src/node/workspace.ts
@@ -115,10 +115,10 @@ export class WorkspaceProject {
     return this.ctx.getCoreWorkspaceProject() === this
   }
 
-  provide = <T extends keyof ProvidedContext>(
+  provide<T extends keyof ProvidedContext & string>(
     key: T,
     value: ProvidedContext[T],
-  ) => {
+  ) {
     try {
       structuredClone(value)
     }
@@ -157,7 +157,7 @@ export class WorkspaceProject {
 
     for (const globalSetupFile of this._globalSetups) {
       const teardown = await globalSetupFile.setup?.({
-        provide: this.provide,
+        provide: (key, value) => this.provide(key, value),
         config: this.config,
       })
       if (teardown == null || !!globalSetupFile.teardown) {