mirror of
https://github.com/hanzoai/next.js.git
synced 2026-09-24 17:00:51 +00:00
Andrew ImmandGitHub
ca414736ba
Add agentName to anonymous telemetry metadata ### What Adds an agentName: string | null field to the anonymous telemetry metadata block that accompanies every payload, alongside existing fields like ciName, nextVersion, and isCI. The value is the detected AI coding agent driving the process (e.g. claude, cursor, codex), or null when none is detected. ### Why We currently have no visibility into how much Next.js development happens under AI coding agents. This field lets us understand that split in the same anonymous way we already track other CLI usage. ### How Agent detection via @vercel/detect-agent - Vendored @vercel/detect-agent (from the Vercel CLI) into `next/dist/compiled/@vercel/detect-agent` (new taskfile ncc task, externals entry, and type declaration), matching how I *understand* other third-party deps are bundled. - The vendored detection method is async (it does a filesystem probe for Devin in addition to env-var checks) and potentially slower than we'd want for logging, so it's wrapped in a memoized helper: `telemetry/agent-name.ts`. `getAgentName()` caches the promise from `determineAgent()`: the first call runs detection once, concurrent callers share that in-flight promise, and every later call resolves against the already-settled result. The agent shouldn't change over the process lifetime, so this is safe. Detection failures resolve to null so telemetry never throws on this path. Wiring into the payload - `getAnonymousMeta()` is now async and includes `agentName: await getAgentName()`. `storage.ts` awaits it on the send path (the record method was thankfully already async). - The NEXT_TELEMETRY_DEBUG=1 output now includes the meta block alongside each event, so the full payload — including agentName — is observable locally without sending anything. We didn't output this before, so it was harder to debug these fields. Consolidating agent detection - There was a second, synchronous, hand-vendored copy of agent detection (telemetry/detect-agent.ts) used only by the AGENTS.md/CLAUDE.md auto-generation hook. It's been removed and that hook (ensureAgentRulesForDev) now uses the same vendored `getAgentName()`. Now we have a single source of truth and can easily get upstream changes from the vercel CLI package. `ensureAgentRulesForDev` became async, its only caller in start-server.ts was already in an async scope, so this is easy. ### Testing - NEXT_TELEMETRY_DEBUG=1 next build shows agentName in the payload meta block next to ciName/nextVersion. - Verified the memoized helper: agent present -> name; cleared env -> null; repeated calls return the same promise instantly. - agent-rules-auto-generate dev tests pass (agent-detected generates files; cleared-env does not) - next-server-nft trace snapshot updated: adds @vercel/detect-agent + agent-name.js, removes detect-agent.js. - ts, build, existing telemetry unit test, lint