Adopt Oxc lint and format tooling for MCP and root

.oxfmtrc.json

@@ -0,0 +1,13 @@
+{
+  "$schema": "./node_modules/oxfmt/configuration_schema.json",
+  "printWidth": 80,
+  "tabWidth": 2,
+  "sortPackageJson": false,
+  "ignorePatterns": [
+    "apps/cli-docs/**",
+    "packages/cli/**",
+    "packages/mcp-server-mocks/src/fixtures/**",
+    "**/worker-configuration.d.ts",
+    "**/tsconfig*.json"
+  ]
+}

.oxlintrc.json

@@ -0,0 +1,26 @@
+{
+  "$schema": "./node_modules/oxlint/configuration_schema.json",
+  "plugins": ["eslint", "typescript", "unicorn", "oxc", "jsx-a11y"],
+  "categories": {
+    "correctness": "error"
+  },
+  "ignorePatterns": [
+    "apps/cli-docs/**",
+    "packages/cli/**",
+    "**/worker-configuration.d.ts",
+    "**/tsconfig*.json",
+    "packages/mcp-server-mocks/src/fixtures/**"
+  ],
+  "rules": {
+    "no-unused-vars": "off",
+    "jsx-a11y/interactive-supports-focus": "off"
+  },
+  "overrides": [
+    {
+      "files": ["packages/mcp-cloudflare/src/client/**/*.tsx"],
+      "rules": {
+        "jsx-a11y/no-static-element-interactions": "off"
+      }
+    }
+  ]
+}

.vscode/extensions.json

@@ -1,4 +1,4 @@
 {
-  "recommendations": ["biomejs.biome"],
+  "recommendations": ["oxc.oxc-vscode", "biomejs.biome"],
   "unwantedRecommendations": []
 }

.vscode/settings.json

@@ -1,21 +1,18 @@
 {
+  "editor.defaultFormatter": "oxc.oxc-vscode",
   "editor.formatOnSave": true,
+  "editor.formatOnSaveMode": "file",
   "editor.codeActionsOnSave": {
-    "source.fixAll.biome": "explicit"
+    "source.fixAll.oxc": "explicit"
   },
   "files.trimTrailingWhitespace": false,
   "files.trimFinalNewlines": false,
   "files.insertFinalNewline": true,
   "cursor.general.enableShadowWorkspace": true,
   "[json]": {
-    "editor.tabSize": 2,
-    "editor.defaultFormatter": "biomejs.biome"
+    "editor.tabSize": 2
   },
   "[typescript]": {
-    "editor.tabSize": 2,
-    "editor.defaultFormatter": "biomejs.biome"
-  },
-  "[typescriptreact]": {
-    "editor.defaultFormatter": "biomejs.biome"
+    "editor.tabSize": 2
   }
 }

docs/contributing/coding-guidelines.md

@@ -20,18 +20,27 @@ Essential patterns and standards for Sentry MCP development.
 
 ## Code Style
 
-### Biome Configuration
+### Formatting and linting
+
 - 2 spaces, double quotes, semicolons
-- Max line: 100 chars
+- Formatter width: 80 characters
 - Trailing commas in multiline
+- MCP and root files use Oxfmt and Oxlint; CLI files still use their own Biome rules.
+- CLI's custom Grit rules and inline suppressions remain active until their
+  equivalents are available in the new linter.
+- VS Code uses Oxc for root and MCP files. Oxfmt ignores `packages/cli/**`;
+  use `pnpm --filter sentry exec biome format --write <file>` to format a CLI
+  file and keep CLI's Biome checks in the pre-commit hook.
 
 ### Naming Conventions
+
 - Files: `kebab-case.ts`
 - Functions: `camelCase`
 - Types/Classes: `PascalCase`
 - Constants: `UPPER_SNAKE_CASE`
 
 ### Import Order
+
 ```typescript
 // 1. Node built-ins
 import { readFile } from "node:fs/promises";
@@ -50,14 +59,14 @@ export const toolName = {
   description: "Clear, concise description",
   parameters: z.object({
     required: z.string().describe("Description"),
-    optional: z.string().optional()
+    optional: z.string().optional(),
   }),
   execute: async (params, context) => {
     // 1. Validate inputs
     // 2. Call API
     // 3. Format output
     return formatResponse(data);
-  }
+  },
 };
 ```
 
@@ -68,17 +77,18 @@ describe("Component", () => {
   it("handles normal case", async () => {
     // Arrange
     const input = createTestInput();
-    
+
     // Act
     const result = await method(input);
-    
+
     // Assert
     expect(result).toMatchInlineSnapshot();
   });
 });
 ```
 
 Key practices:
+
 - Use inline snapshots for formatting
 - Mock with MSW
 - Test success and error paths
@@ -87,29 +97,32 @@ Key practices:
 ## Quality Checklist
 
 Before committing:
+
 ```bash
-pnpm -w run lint        # Biome check
+pnpm -w run lint        # Oxlint and ast-grep checks for MCP and root files
 pnpm -w run lint:fix    # Fix issues
+pnpm -w run format      # Format MCP and root files with Oxfmt
+pnpm --filter sentry run lint  # CLI Biome rules
 pnpm tsc --noEmit       # Type check
 pnpm test               # Run tests
 pnpm -w run build       # Build all
 ```
 
 ## JSDoc Pattern
 
-```typescript
+````typescript
 /**
  * Brief description.
- * 
+ *
  * @param param - Description
  * @returns What it returns
- * 
+ *
  * @example
  * ```typescript
  * const result = func(param);
  * ```
  */
-```
+````
 
 ## Security Essentials
 
@@ -121,6 +134,7 @@ pnpm -w run build       # Build all
 ## Common Patterns
 
 For shared patterns see:
+
 - Error handling: [common-patterns.md](common-patterns.md#error-handling)
 - Zod schemas: [common-patterns.md](common-patterns.md#zod-schema-patterns)
 - API usage: [api-patterns.md](api-patterns.md)

package.json

@@ -23,7 +23,7 @@
   },
   "scripts": {
     "docs:check": "node scripts/check-doc-links.mjs",
-    "test:ci-projects": "node --test scripts/ci-projects.test.mjs scripts/cli-nightly-version.test.mjs scripts/cloudflare-deployment.test.mjs scripts/deploy-workflow.test.mjs scripts/migrate-cloudflare-token.test.mjs",
+    "test:ci-projects": "node --test scripts/ci-projects.test.mjs scripts/cli-nightly-version.test.mjs scripts/cloudflare-deployment.test.mjs scripts/deploy-workflow.test.mjs scripts/migrate-cloudflare-token.test.mjs scripts/oxc-config.test.mjs",
     "dev": "pnpm --filter '@sentry/mcp-cloudflare...' --if-present run build && dotenv -e .env -e .env.local -- pnpm --parallel --filter @sentry/mcp-cloudflare --filter @sentry/mcp-core --filter @sentry/mcp-server-mocks --if-present run dev",
     "dev:stdio": "pnpm --filter '@sentry/mcp-server...' --if-present run build && dotenv -e .env -e .env.local -- pnpm --parallel --filter @sentry/mcp-server --filter @sentry/mcp-core --filter @sentry/mcp-server-mocks --if-present run dev",
     "build": "dotenv -e .env -e .env.local -- pnpm -r --filter '!sentry' --filter '!sentry-cli-docs' --if-present run build",
@@ -32,10 +32,10 @@
     "deploy:docs": "pnpm --filter sentry run generate:schema && pnpm --filter sentry run generate:docs && pnpm --filter sentry-cli-docs run build && pnpm --filter sentry-cli-docs run deploy",
     "eval": "pnpm --filter '@sentry/mcp-server-evals...' --if-present run build && dotenv -e .env -e .env.local -- pnpm --filter @sentry/mcp-server-evals run eval",
     "eval:ci": "pnpm --filter '@sentry/mcp-server-evals...' --if-present run build && CI=true dotenv -e .env -e .env.local -- pnpm --stream -r run eval:ci",
-    "format": "biome format --write",
-    "lint": "biome lint && pnpm run lint:ast-grep",
+    "format": "oxfmt --write",
+    "lint": "oxlint . && pnpm run lint:ast-grep",
     "lint:ast-grep": "ast-grep scan && ast-grep test --skip-snapshot-tests",
-    "lint:fix": "biome lint --fix",
+    "lint:fix": "oxlint --fix .",
     "pre-commit:generated": "node scripts/pre-commit-generated.mjs",
     "inspector": "pnpx @modelcontextprotocol/inspector@latest",
     "inspector:stdio": "pnpx @modelcontextprotocol/inspector@latest -- tsx packages/mcp-server/src/index.ts",
@@ -50,11 +50,12 @@
   },
   "dependencies": {
     "@ast-grep/cli": "catalog:",
-    "@biomejs/biome": "catalog:",
     "@types/node": "catalog:",
     "dotenv": "catalog:",
     "dotenv-cli": "catalog:",
     "lint-staged": "catalog:",
+    "oxfmt": "catalog:",
+    "oxlint": "catalog:",
     "simple-git-hooks": "catalog:",
     "tsdown": "catalog:",
     "tsx": "catalog:",
@@ -68,8 +69,12 @@
   },
   "lint-staged": {
     "*": [
-      "biome format --write --no-errors-on-unmatched --files-ignore-unknown=true",
-      "biome lint --fix --no-errors-on-unmatched --files-ignore-unknown=true"
+      "oxfmt --write --no-error-on-unmatched-pattern",
+      "oxlint --fix --no-error-on-unmatched-pattern"
+    ],
+    "packages/cli/**/*": [
+      "pnpm --filter sentry exec biome format --write --no-errors-on-unmatched --files-ignore-unknown=true",
+      "pnpm --filter sentry exec biome lint --fix --no-errors-on-unmatched --files-ignore-unknown=true"
     ]
   },
   "devDependencies": {

packages/mcp-cloudflare/src/client/components/animation/terminal-ui/StepsList.test.ts

@@ -0,0 +1,44 @@
+import {
+  Children,
+  isValidElement,
+  type KeyboardEvent,
+  type KeyboardEventHandler,
+} from "react";
+import { describe, expect, it, vi } from "vitest";
+import StepsList from "./StepsList";
+
+const steps = Array.from({ length: 6 }, (_, index) => ({
+  label: `Step ${index}`,
+  description: "",
+  startTime: 0,
+  pauseMs: null,
+}));
+
+describe("StepsList keyboard navigation", () => {
+  it.each(["Enter", " "])("restarts from the final step with %j", (key) => {
+    const restart = vi.fn();
+    const onSelectAction = vi.fn();
+    const element = StepsList({
+      steps,
+      globalIndex: steps.length - 1,
+      onSelectAction,
+      restart,
+    });
+    const button = Children.toArray(element.props.children).find(
+      (child) => isValidElement(child) && child.type === "button",
+    );
+    if (!isValidElement<{ onKeyDown: KeyboardEventHandler }>(button)) {
+      throw new Error("Step navigation button is missing");
+    }
+
+    const preventDefault = vi.fn();
+    button.props.onKeyDown({
+      key,
+      preventDefault,
+    } as unknown as KeyboardEvent<HTMLButtonElement>);
+
+    expect(preventDefault).toHaveBeenCalledOnce();
+    expect(restart).toHaveBeenCalledOnce();
+    expect(onSelectAction).not.toHaveBeenCalled();
+  });
+});

packages/mcp-cloudflare/src/client/components/animation/terminal-ui/StepsList.tsx

@@ -108,8 +108,8 @@ export default function StepsList({
         onKeyDown={(e) => {
           if (e.key === "Enter" || e.key === " ") {
             e.preventDefault();
-            if (globalIndex === 6) {
-              typeof restart === "function" && restart();
+            if (globalIndex === 5) {
+              if (typeof restart === "function") restart();
             } else {
               onSelectAction(Math.min(globalIndex + 1, steps.length - 1));
             }

packages/mcp-cloudflare/src/client/components/fragments/install-tabs.tsx

@@ -109,7 +109,7 @@ export default function InstallTabs({
     const from = c.offsetHeight;
     const to = next.offsetHeight;
     c.style.height = `${from}px`;
-    c.offsetHeight;
+    void c.offsetHeight;
     c.style.transition = "height 300ms cubic-bezier(0.2, 0.8, 0.2, 1)";
     c.style.height = `${to}px`;
     const done = () => {

packages/mcp-core/package.json

@@ -151,7 +151,7 @@
     "test:ci": "pnpm run generate-definitions && pnpm run validate-skills && vitest run --reporter=default --reporter=junit --outputFile=tests.junit.xml",
     "test:watch": "pnpm run generate-definitions && vitest",
     "tsc": "tsc --noEmit",
-    "generate-definitions": "tsx scripts/generate-definitions.ts && biome format --write src/toolDefinitions.json src/skillDefinitions.json",
+    "generate-definitions": "tsx scripts/generate-definitions.ts && oxfmt --write src/toolDefinitions.json src/skillDefinitions.json",
     "generate-otel-namespaces": "tsx scripts/generate-otel-namespaces.ts",
     "measure-tokens": "tsx scripts/measure-token-cost.ts",
     "validate-skills": "tsx scripts/validate-skills-mapping.ts"

packages/mcp-core/src/telem/logging.ts

@@ -408,7 +408,7 @@ export function logIssue(
 
   const { attachments, ...baseOptions } = options;
   const extra: LogContext = {
-    ...(baseOptions.extra ?? {}),
+    ...baseOptions.extra,
     ...(attachments && Object.keys(attachments).length > 0
       ? { attachments: Object.keys(attachments) }
       : {}),