Fix MDX parser error in mapping.mdx documentation

[Copilot]

Vercel build failed with MDX parsing error at mapping.mdx:44:99 - the parser interpreted unescaped curly braces in a table cell as JSX expression syntax.

Changes

• Escaped inline JSON example in table description by wrapping in backticks

-| **valueMap** | `Record<string, any>` | optional | Value mapping for map transform (e.g. { "Open": "draft" }) |
+| **valueMap** | `Record<string, any>` | optional | Value mapping for map transform (e.g. `{ "Open": "draft" }`) |

This aligns with the pattern used elsewhere in the docs (e.g., field.mdx:106, license.mdx:77).

Original prompt

拉取请求: #189

13:58:55.637 Running build in Washington, D.C., USA (East) – iad1
13:58:55.638 Build machine configuration: 4 cores, 8 GB
13:58:55.772 Cloning github.com/objectstack-ai/spec (Branch: dependabot/npm_and_yarn/production-dependencies-29f96a6100, Commit: aa54256)
13:58:57.037 Cloning completed: 1.265s
13:58:58.361 Restored build cache from previous deployment (33CdzVeYdQa29oXw8AYx2smX3Bno)
13:58:58.699 Warning: Detected "engines": { "node": ">=18.0.0" } in your package.json that will automatically upgrade when a new major Node.js Version is released. Learn More: https://vercel.link/node-version
13:58:58.699 Running "vercel build"
13:58:59.547 Vercel CLI 50.5.2
13:58:59.801 Warning: Detected "engines": { "node": ">=18.0.0" } in your package.json that will automatically upgrade when a new major Node.js Version is released. Learn More: https://vercel.link/node-version
13:58:59.862 Detected pnpm-lock.yaml version 9 generated by pnpm@10.x with package.json#packageManager pnpm@10.28.1
13:58:59.892 Installing dependencies...
13:59:02.244 Scope: all 21 workspace projects
13:59:03.679
13:59:03.739 Done in 1.9s using pnpm v10.28.1
13:59:03.766 Detected Next.js version: 16.1.6
13:59:03.793 Running "pnpm run build"
13:59:04.403
13:59:04.404 > @objectstack/docs@0.4.2 build /vercel/path0/apps/docs
13:59:04.404 > next build
13:59:04.404
13:59:05.668 [MDX] generated files in 126.659895ms
13:59:05.675 ▲ Next.js 16.1.6 (Turbopack)
13:59:05.675
13:59:05.683 ⚠ The "middleware" file convention is deprecated. Please use "proxy" instead. Learn more: https://nextjs.org/docs/messages/middleware-to-proxy
13:59:05.709 Creating an optimized production build ...
13:59:42.505
13:59:42.505 > Build error occurred
13:59:42.507 Error: Turbopack build failed with 1 errors:
13:59:42.508 ./content/docs/references/data/mapping.mdx
13:59:42.508 Error evaluating Node.js code
13:59:42.508 44:99: Could not parse expression with acorn
13:59:42.508 Caused by: Error: Unexpected content after expression
13:59:42.508 [at eventsToAcorn (file:///vercel/path0/node_modules/.pnpm/micromark-util-events-to-acorn@2.0.3/node_modules/micromark-util-events-to-acorn/lib/index.js:96:7)]
13:59:42.508 [at Object.mdxExpressionParse (file:///vercel/path0/node_modules/.pnpm/micromark-factory-mdx-expression@2.0.3/node_modules/micromark-factory-mdx-expression/index.js:246:18)]
13:59:42.508 [at before (file:///vercel/path0/node_modules/.pnpm/micromark-factory-mdx-expression@2.0.3/node_modules/micromark-factory-mdx-expression/index.js:129:47)]
13:59:42.508 [at inside (file:///vercel/path0/node_modules/.pnpm/micromark-factory-mdx-expression@2.0.3/node_modules/micromark-factory-mdx-expression/index.js:167:14)]
13:59:42.508 [at go (file:///vercel/path0/node_modules/.pnpm/micromark@4.0.2/node_modules/micromark/lib/create-tokenizer.js:235:13)]
13:59:42.509 [at main (file:///vercel/path0/node_modules/.pnpm/micromark@4.0.2/node_modules/micromark/lib/create-tokenizer.js:216:11)]
13:59:42.509 [at Object.write (file:///vercel/path0/node_modules/.pnpm/micromark@4.0.2/node_modules/micromark/lib/create-tokenizer.js:136:5)]
13:59:42.509 [at subcontent (file:///vercel/path0/node_modules/.pnpm/micromark-util-subtokenize@2.1.0/node_modules/micromark-util-subtokenize/index.js:171:17)]
13:59:42.509 [at subtokenize (file:///vercel/path0/node_modules/.pnpm/micromark-util-subtokenize@2.1.0/node_modules/micromark-util-subtokenize/index.js:69:30)]
13:59:42.509 [at postprocess (file:///vercel/path0/node_modules/.pnpm/micromark@4.0.2/node_modules/micromark/lib/postprocess.js:14:11)]
13:59:42.509
13:59:42.509
13:59:42.509 at ignore-listed frames
13:59:42.629  ELIFECYCLE  Command failed with exit code 1.
13:59:42.660 Error: Command "pnpm run build" exited with 1

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Project	Deployment	Actions	Updated (UTC)
spec	Canceled		Feb 1, 2026 3:25am

[Copilot]

Pull request overview

This PR fixes a critical MDX parsing error that caused the Vercel build to fail. The MDX parser was incorrectly interpreting unescaped curly braces { "Open": "draft" } in a table cell as JSX expression syntax, resulting in an "Unexpected content after expression" error at line 44:99 of mapping.mdx.

Changes:

• Escaped the inline JSON example in the valueMap parameter description by wrapping it in backticks