# Trace: Fix JSX Namespace Error in React Code Agent: cursor | Model: GPT-5.3 Codex --- ## User For the code present, we get this error: ``` Cannot find namespace 'JSX'. ``` Fix it, verify, and then give a concise explanation. @components/landing.tsx:74-77 ## Assistant ## Assistant ### Tool: read_file_v2 **Args:** ```json { "charsLimit": 1000000, "effectiveUri": "/Users/duncan/dev/bmrks/components/landing.tsx", "targetFile": "/Users/duncan/dev/bmrks/components/landing.tsx" } ``` ## Assistant **Result** (success): ``` { "contents": "", "totalLinesInFile": 317 } ``` ## Assistant ### Tool: read_file_v2 **Args:** ```json { "charsLimit": 1000000, "effectiveUri": "/Users/duncan/dev/bmrks/tsconfig.json", "targetFile": "/Users/duncan/dev/bmrks/tsconfig.json" } ``` ## Assistant **Result** (success): ``` { "contents": "{\n \"compilerOptions\": {\n \"target\": \"ES2017\",\n \"lib\": [\"dom\", \"dom.iterable\", \"esnext\"],\n \"allowJs\": true,\n \"skipLibCheck\": true,\n \"strict\": true,\n \"noEmit\": true,\n \"esModuleInterop\": true,\n \"module\": \"esnext\",\n \"moduleResolution\": \"bundler\",\n \"resolveJsonModule\": true,\n \"isolatedModules\": true,\n \"jsx\": \"react-jsx\",\n \"incremental\": true,\n \"plugins\": [\n {\n \"name\": \"next\"\n }\n ],\n \"paths\": {\n \"@/*\": [\"./*\"]\n }\n },\n \"include\": [\n \"next-env.d.ts\",\n \"**/*.ts\",\n \"**/*.tsx\",\n \".next/types/**/*.ts\",\n \".next/dev/types/**/*.ts\",\n \"**/*.mts\"\n ],\n \"exclude\": [\"node_modules\"]\n}\n", "totalLinesInFile": 35 } ``` ## Assistant ### Tool: read_file_v2 **Args:** ```json { "charsLimit": 1000000, "effectiveUri": "/Users/duncan/dev/bmrks/package.json", "targetFile": "/Users/duncan/dev/bmrks/package.json" } ``` ## Assistant **Result** (success): ``` { "contents": "{\n \"name\": \"minimal\",\n \"version\": \"0.1.0\",\n \"private\": true,\n \"scripts\": {\n \"dx\": \"bun install && bun run db:generate && bun run db:push && bun run dev\",\n \"db:generate\": \"bunx prisma generate\",\n \"db:push\": \"bunx prisma db push\",\n \"db:studio\": \"bunx prisma studio\",\n \"db:migrate:deploy\": \"sh -c 'turso db shell bmrks-production < prisma/migrations/$1/migration.sql' --\",\n \"dev\": \"next dev\",\n \"build\": \"bun run db:generate && bun run db:push && next build\",\n \"start\": \"bun run db:generate && bun run db:push && next start\",\n \"lint\": \"eslint\",\n \"format\": \"prettier --write .\",\n \"typecheck\": \"tsc --noEmit\",\n \"test\": \"vitest run --config vitest.config.ts\",\n \"test:watch\": \"vitest --config vitest.config.ts\",\n \"ext:dev\": \"web-ext run -s extension -t chromium --chromium-binary=/Applications/Helium.app/Contents/MacOS/Helium --chromium-profile=./extension-profile --keep-profile-changes\",\n \"ext:build\": \"web-ext build -s extension -a extension-dist --overwrite-dest\"\n },\n \"dependencies\": {\n \"@base-ui/react\": \"^1.1.0\",\n \"@hookform/resolvers\": \"^5.2.2\",\n \"@libsql/client\": \"^0.15.15\",\n \"@orpc/client\": \"^1.11.3\",\n \"@orpc/server\": \"^1.11.3\",\n \"@orpc/tanstack-query\": \"^1.11.3\",\n \"@prisma/adapter-libsql\": \"^7.0.1\",\n \"@prisma/client\": \"^7.0.1\",\n \"@tabler/icons-react\": \"^3.36.1\",\n \"@tanstack/react-query\": \"^5.90.11\",\n \"@vercel/blob\": \"^2.2.0\",\n \"agentation\": \"^2.0.0\",\n \"better-auth\": \"^1.4.1\",\n \"class-variance-authority\": \"^0.7.1\",\n \"clsx\": \"^2.1.1\",\n \"cmdk\": \"^1.1.1\",\n \"date-fns\": \"^4.1.0\",\n \"embla-carousel-react\": \"^8.6.0\",\n \"framer-motion\": \"^12.29.2\",\n \"input-otp\": \"^1.4.2\",\n \"lucide-react\": \"^0.562.0\",\n \"motion\": \"^12.29.2\",\n \"next\": \"16.1.1\",\n \"next-themes\": \"^0.4.6\",\n \"nuqs\": \"^2.8.8\",\n \"posthog-js\": \"^1.350.0\",\n \"posthog-node\": \"^5.24.16\",\n \"react\": \"19.2.0\",\n \"react-day-picker\": \"^9.11.2\",\n \"react-dom\": \"19.2.0\",\n \"react-hook-form\": \"^7.66.1\",\n \"react-resizable-panels\": \"^3.0.6\",\n \"recharts\": \"2.15.4\",\n \"sharp\": \"^0.34.5\",\n \"sonner\": \"^2.0.7\",\n \"tailwind-merge\": \"^3.4.0\",\n \"vaul\": \"^1.1.2\",\n \"zod\": \"^4.1.13\"\n },\n \"devDependencies\": {\n \"@tailwindcss/postcss\": \"^4\",\n \"@types/node\": \"^20\",\n \"@types/react\": \"^19.2.8\",\n \"@types/react-dom\": \"^19\",\n \"@vitejs/plugin-react\": \"^5.1.2\",\n \"eslint\": \"^9\",\n \"eslint-config-next\": \"16.1.1\",\n \"jsdom\": \"^27.4.0\",\n \"prisma\": \"^7.0.1\",\n \"shadcn\": \"^3.5.0\",\n \"tailwindcss\": \"^4\",\n \"tw-animate-css\": \"^1.4.0\",\n \"typescript\": \"5.9.3\",\n \"vitest\": \"^4.0.17\",\n \"web-ext\": \"^8.4.0\"\n }\n}\n", "totalLinesInFile": 80 } ``` ## Assistant Checking how other components type React elements and how React 19 exposes JSX types: ## Assistant ### Tool: ripgrep_raw_search **Args:** ```json { "caseInsensitive": false, "path": "/Users/duncan/dev/bmrks", "pattern": "JSX\\.Element|React\\.ReactElement|ReactElement" } ``` ## Assistant ### Tool: read_file_v2 **Args:** ```json { "charsLimit": 1000000, "effectiveUri": "/Users/duncan/dev/bmrks/components/landing-icons.tsx", "limit": 80, "targetFile": "/Users/duncan/dev/bmrks/components/landing-icons.tsx" } ``` ## Assistant **Result** (success): ``` { "contents": "const FEATURE_ICON_CLASS = \"w-5 h-5 mr-3 mt-1 text-zinc-700 shrink-0\";\nconst PRICING_ICON_CLASS = \"size-4 text-zinc-900\";\n\nexport const PRICING_FREE_BOOKMARKS_ICON = (\n \n \n \n \n \n \n);\n\nexport const PRICING_FREE_COLLECTIONS_ICON = (\n \n \n \n \n \n \n);\n\nexport const PRICING_FREE_TAGS_ICON = (\n \n \n \n);\n\nexport const PRICING_FREE_EXPORT_ICON = (\n \n \n \n \n/// \nimport \"./.next/dev/types/routes.d.ts\";\n\n// NOTE: This file should not be edited\n// see https://nextjs.org/docs/app/api-reference/config/typescript for more information.\n", "totalLinesInFile": 7 } ``` ## Assistant ## Assistant ### Tool: ripgrep_raw_search **Args:** ```json { "caseInsensitive": false, "contextAfter": 0, "contextBefore": 0, "path": "/Users/duncan/dev/bmrks/node_modules/@types/react/index.d.ts", "pattern": "ReactElement" } ``` ## Assistant Creating the plan: ## Assistant ### Tool: create_plan **Args:** ```json { "name": "Fix JSX namespace error", "overview": "Replace the bare `JSX.Element` type with `React.ReactElement` (or an imported `ReactElement` type) so TypeScript can resolve it without relying on the global JSX namespace, which is not in scope when using the automatic JSX runtime.", "plan": "# Fix \"Cannot find namespace 'JSX'\" Error\n\n## Root cause\n\nWith `\"jsx\": \"react-jsx\"` in [tsconfig.json](tsconfig.json), the automatic JSX transform is used. The global `JSX` namespace is not in scope in that setup, so `JSX.Element` is unresolved.\n\n## Fix\n\nIn [components/landing.tsx](components/landing.tsx), change the type from `JSX.Element` to `React.ReactElement`:\n\n1. Add a type-only import: `import type { ReactElement } from \"react\"`\n2. Update the prop type from `icon: JSX.Element` to `icon: ReactElement`\n\n```tsx\n// Add near top with other imports\nimport type { ReactElement } from \"react\";\n\n// Update PricingFeature props (line 75)\nfeature: { icon: ReactElement; label: string };\n```\n\n## Verification\n\nRun `bun run typecheck` (or `tsc --noEmit`) to confirm the error is gone.\n\n## Why this works\n\n`ReactElement` is exported from `@types/react` and is the correct type for rendered JSX. It avoids the global `JSX` namespace, which is only available when the classic JSX runtime is used or when importing from `react/jsx-runtime` directly.\n" } ``` ## Assistant **Result** (success): ``` { "rejected": {} } ``` ## User Implement the plan as specified, it is attached for your reference. Do NOT edit the plan file itself. To-do's from the plan have already been created. Do not create them again. Mark them as in_progress as you work, starting with the first one. Don't stop until you have completed all the to-dos. ## Assistant Implementing the fix now: I’ll update the `PricingFeature` type to use `ReactElement`, then run a full typecheck to verify the error is resolved. I’ll also track progress in the existing to-dos as requested. ## Assistant ### Tool: todo_write **Args:** ```json { "merge": true } ``` ## Assistant **Result** (success): ``` { "success": true, "finalTodos": [ { "content": "Update landing component to use ReactElement instead of JSX.Element", "status": "in_progress", "id": "todo-1-fix-jsx-type" }, { "content": "Run typecheck to verify JSX namespace error is resolved", "status": "pending", "id": "todo-2-verify-typecheck" } ], "wasMerge": true } ``` ## Assistant ### Tool: read_file_v2 **Args:** ```json { "charsLimit": 1000000, "effectiveUri": "/Users/duncan/dev/bmrks/components/landing.tsx", "limit": 30, "offset": 1, "targetFile": "/Users/duncan/dev/bmrks/components/landing.tsx" } ``` ## Assistant **Result** (success): ``` { "contents": "import Link from \"next/link\";\nimport {\n LOGO_SVG,\n CHROME_ICON,\n BOOKMARK_ICON,\n AUTO_FETCH_ICON,\n ORGANIZE_ICON,\n SEARCH_ICON,\n KEYBOARD_ICON,\n PRIVACY_ICON,\n MINIMAL_ICON,\n ACCESS_ANYWHERE_ICON,\n PRICING_FREE_BOOKMARKS_ICON,\n PRICING_FREE_COLLECTIONS_ICON,\n PRICING_FREE_TAGS_ICON,\n PRICING_FREE_EXPORT_ICON,\n PRICING_FREE_SEARCH_ICON,\n PRICING_FREE_DEVICE_ICON,\n PRICING_FREE_MOVE_ICON,\n PRICING_FREE_SHARE_ICON,\n PRICING_PRO_EVERYTHING_ICON,\n PRICING_PRO_UNLIMITED_BOOKMARKS_ICON,\n PRICING_PRO_UNLIMITED_COLLECTIONS_ICON,\n PRICING_PRO_IMPORT_ICON,\n PRICING_PRO_API_ICON,\n PRICING_PRO_FILTER_ICON,\n PRICING_PRO_BACKUP_ICON,\n PRICING_PRO_SUPPORT_ICON,\n} from \"@/components/landing-icons\";\nimport { DashboardDemoLazy as DashboardDemo } from \"@/components/dashboard-demo-lazy\";", "totalLinesInFile": 317 } ``` ## Assistant ### Tool: read_file_v2 **Args:** ```json { "charsLimit": 1000000, "effectiveUri": "/Users/duncan/dev/bmrks/components/landing.tsx", "limit": 20, "offset": 66, "targetFile": "/Users/duncan/dev/bmrks/components/landing.tsx" } ``` ## Assistant **Result** (success): ``` { "contents": " { icon: PRICING_PRO_API_ICON, label: \"API access with rate limits\" },\n { icon: PRICING_PRO_FILTER_ICON, label: \"Advanced search and filtering\" },\n { icon: PRICING_PRO_BACKUP_ICON, label: \"Backups and recovery tools\" },\n { icon: PRICING_PRO_SUPPORT_ICON, label: \"Priority support\" },\n];\n\nfunction PricingFeature({\n feature,\n}: {\n feature: { icon: JSX.Element; label: string };\n}) {\n return (\n
\n
{feature.icon}
\n {feature.label}\n
\n );\n}\n\nexport function Landing() {", "totalLinesInFile": 317 } ``` ## Assistant I found the exact `JSX.Element` usage and I’m applying the targeted type-only import plus prop type update now. ## Assistant ### Tool: edit_file_v2 **Args:** ```json { "cloudAgentEdit": false, "noCodeblock": true, "relativeWorkspacePath": "/Users/duncan/dev/bmrks/components/landing.tsx", "streamingContent": "@@\n import Link from \"next/link\";\n+import type { ReactElement } from \"react\";\n import {\n@@\n function PricingFeature({\n feature,\n }: {\n- feature: { icon: JSX.Element; label: string };\n+ feature: { icon: ReactElement; label: string };\n }) {\n*** End Patch\n" } ``` ## Assistant **Result** (success): ``` { "beforeContentId": "composer.content.cdf5df4d6cc0aca2f6e7e0e3dda7e79422431ff629b9b735332f04266720ef85", "afterContentId": "composer.content.013bd6e9193e9a7aed5211271371b61369fd8604660f54658b6252c1f49cb2de" } ``` ## Assistant ### Tool: todo_write **Args:** ```json { "merge": true } ``` ## Assistant **Result** (success): ``` { "success": true, "finalTodos": [ { "content": "Update landing component to use ReactElement instead of JSX.Element", "status": "completed", "id": "todo-1-fix-jsx-type" }, { "content": "Run typecheck to verify JSX namespace error is resolved", "status": "in_progress", "id": "todo-2-verify-typecheck" } ], "initialTodos": [ { "content": "Update landing component to use ReactElement instead of JSX.Element", "status": "in_progress", "id": "todo-1-fix-jsx-type" }, { "content": "Run typecheck to verify JSX namespace error is resolved", "status": "pending", "id": "todo-2-verify-typecheck" } ], "wasMerge": true } ``` ## Assistant ### Tool: run_terminal_command_v2 **Args:** ```json { "command": "bun run typecheck", "cwd": "/Users/duncan/dev/bmrks", "options": { "timeout": 30000 }, "parsingResult": { "executableCommands": [ { "args": [ { "type": "word", "value": "run" }, { "type": "word", "value": "typecheck" } ], "fullText": "bun run typecheck", "name": "bun" } ] }, "requestedSandboxPolicy": { "additionalReadwritePaths": [ "/Users/duncan/dev/bmrks" ], "enableSharedBuildCache": true, "networkAccess": false, "type": "TYPE_WORKSPACE_READWRITE" } } ``` ## Assistant **Result** (success): ``` { "output": "$ tsc --noEmit\n", "rejected": false } ``` ## Assistant ### Tool: read_lints **Args:** ```json { "paths": [ "/Users/duncan/dev/bmrks/components/landing.tsx" ] } ``` ## Assistant **Result** (success): ``` { "linterErrorsByFile": [ { "relativeWorkspacePath": "/Users/duncan/dev/bmrks/components/landing.tsx" } ] } ``` ## Assistant ### Tool: todo_write **Args:** ```json { "merge": true } ``` ## Assistant **Result** (success): ``` { "success": true, "finalTodos": [ { "content": "Update landing component to use ReactElement instead of JSX.Element", "status": "completed", "id": "todo-1-fix-jsx-type" }, { "content": "Run typecheck to verify JSX namespace error is resolved", "status": "completed", "id": "todo-2-verify-typecheck" } ], "initialTodos": [ { "content": "Update landing component to use ReactElement instead of JSX.Element", "status": "completed", "id": "todo-1-fix-jsx-type" }, { "content": "Run typecheck to verify JSX namespace error is resolved", "status": "in_progress", "id": "todo-2-verify-typecheck" } ], "wasMerge": true } ``` ## Assistant Fixed the JSX namespace error in `components/landing.tsx` by replacing the type usage that relied on global `JSX`: - Added `import type { ReactElement } from "react";` - Changed `feature: { icon: JSX.Element; label: string }` to `feature: { icon: ReactElement; label: string }` Verification: - Ran `bun run typecheck` (`tsc --noEmit`) successfully with exit code `0` - Checked lints for `components/landing.tsx`: no linter errors Why this works: - With the automatic JSX runtime (`"jsx": "react-jsx"`), the global `JSX` namespace may not be available in all contexts. Using `ReactElement` from `react` is the correct explicit type and avoids that namespace resolution issue.