[devtools-agent]

Linear: SDK-801 · Closes #125

What changed

• examples/nextjs-approuter/src/proxy.ts (new): reports errors with the shared serverInstance. A matcher limits it to a /proxy_error demo route, which throws, reports to Rollbar and returns a 500. Request data goes in per call (rollbar.error(err, { pathname })) and not through rollbar.configure(), because configure() would change the instance every concurrent request shares. That was the pattern in the original issue.
• examples/nextjs-approuter/README.md: new section Reporting errors from proxy.ts (formerly middleware.ts) that explains the Edge-runtime 403 and gives three options: rename to proxy.ts on Next 16, use runtime: 'nodejs' on Next 15.5 and later, or create a separate new Rollbar(clientConfig) instance if the middleware has to stay on Edge. The env var names in the README snippet now match src/rollbar.ts (NEXT_PUBLIC_ROLLBAR_CLIENT_TOKEN / ROLLBAR_SERVER_TOKEN); before, the snippet used different names than the code.
• README.md: one paragraph under Using with Next.js App Router that links to the new section.
• src/__tests__/proxy.test.tsx (new): checks that the proxy reports through serverInstance with per-call data, never calls configure(), returns a 500 on the demo route and passes other requests through.

Why

#125 is a docs/example gap, not an SDK bug. On the Edge runtime the bundler resolves rollbar through the browser export condition, so middleware gets the browser build. That build sends platform: browser items, and the API rejects them when they come with a post_server_item token.

Validation

Run against Next 16.3.8 and rollbar 3.1.0, with endpoint temporarily pointed at a local listener so the payloads could be inspected:

Setup	Bundled build	Item sent with server token
middleware.ts (Edge, default)	rollbar-browser-js	platform: browser → 403 on the real API (reproduces #125)
middleware.ts + runtime: 'nodejs'	node_rollbar	server item, accepted
proxy.ts (this PR)	node_rollbar	server item, accepted

• next build and next start with the new proxy.ts: GET /proxy_error returned 500 and sent one node_rollbar item; GET / returned 200 and sent nothing.
• jest --ci: 4 suites and 5 tests pass. eslint . --max-warnings 0 and tsc --noEmit pass, and prettier passes on the changed files.

🤖 Generated with Claude Code

[linear-code]

SDK-801

CR-577

[devtools-agent]

AI Agent Review (openai, openai-astra)

Review: document reporting from Next.js proxy.ts / middleware

I found nothing in the changed lines that needs fixing. I read the new and changed files against the example's code and the pinned dependencies.

What I checked

• examples/nextjs-approuter/src/proxy.ts:10-30 uses the shared serverInstance and passes request data per call (rollbar.error(error as Error, { pathname })). That call matches rollbar 3.1.0's types: error(...args: LogArgument[]) takes an Error and a plain object (node_modules/rollbar/index.d.ts:20,165-173). The code never calls configure(). Next.js is pinned to 16.3.8 (examples/nextjs-approuter/package.json:15, examples/nextjs-approuter/package-lock.json:7895), and proxy.ts is the Next 16 convention.
• The PR says the Edge runtime gets rollbar's browser build. That fits rollbar 3.1.0's export map, which has separate node and browser entries (node_modules/rollbar/package.json:22-33).
• The env var names in the example README snippet now match the real code (examples/nextjs-approuter/src/rollbar.ts:10,15 vs examples/nextjs-approuter/README.md:34,39).
• The test's jest.mock('../rollbar') should also cover the proxy's @/rollbar import, because both resolve to the same file. Another test in the same suite already imports through @/ (examples/nextjs-approuter/src/__tests__/next-error-handler.test.tsx:4). The test file uses .tsx because testMatch only picks up *.test.tsx (examples/nextjs-approuter/jest.config.js:9). Its @jest-environment node docblock replaces the default jsdom environment for this file only.
• As far as I can check by hand, the new code follows the repo's prettier config (prettier.config.js:4-7: single quotes, trailing commas, default width). CI runs it on examples/, which is not in .prettierignore.
• The root README link anchor #reporting-errors-from-proxyts-formerly-middlewarets matches the GitHub slug of the new heading (examples/nextjs-approuter/README.md:70).
• The example tests run in CI through npm run test:examples (.github/workflows/ci.yaml:76-77). I could not run them, so I am not claiming they pass.

Existing issues in unchanged lines (not findings)

• The root README.md snippet still uses the old env var names NEXT_PUBLIC_POST_CLIENT_ITEM_TOKEN / POST_SERVER_ITEM_TOKEN (README.md:156,161). This PR fixed the same mismatch in the example README, so the two READMEs now disagree. Worth updating while you're here.
• examples/nextjs-approuter/README.md:60 has an empty link [error handler]() and a double slash in ./src/app//next_error_handler/error.tsx.

Optional suggestions

• Edge option (examples/nextjs-approuter/README.md:105): if a reader imports clientConfig from @/rollbar into Edge middleware, the import also runs new Rollbar(...) with the server token (examples/nextjs-approuter/src/rollbar.ts:14-17). Edge would load the browser build, and the config has captureUncaught/captureUnhandledRejections turned on (examples/nextjs-approuter/src/rollbar.ts:3-7). The browser build attaches its global handlers to self when there is no window (node_modules/rollbar/src/browser/core.js:208-231,581-585). I did not check whether Edge ever fires those handlers. It may still be worth saying to define the Edge instance in an Edge-only module.
• The proxy returns without waiting for the report to send. That works with next start, which is what the PR says it validated. If the docs are meant to cover serverless hosts, they could mention rollbar's wait() flush API (node_modules/rollbar/index.d.ts:22).

The PR description declares no dependencies on other PRs; it only references issue #125 and SDK-801.