Use when editing worker/src/constants/default-model-prices.json, packages/shared/src/server/llm/types.ts, pricing tiers, tokenizer IDs, or matchPattern regexes for OpenAI, Anthropic, Bedrock, Vertex, Azure, or Gemini model pricing.
Instrument Langfuse with PostHog product analytics, and decide whether new frontend work should be instrumented. Use when (1) adding a meaningful user action to the frontend — a button, onClick/onSubmit handler, form, dialog, toggle, tRPC mutation call, or a new feature surface in `web/**` — pause and propose instrumentation before finishing; (2) asked to instrument a feature, add analytics or usage tracking, or answer "how do people use X"; (3) adding or reviewing `capture()` events, `usePostHogClientCapture`, or any code that touches `posthog`.
Upgrade pnpm workspace dependencies to target/latest versions: direct/transitive bumps, release-age checks, temporary overrides, minimumReleaseAgeExclude, lockfile/dedupe verification.
Seed local Langfuse test data with one command: large/branching observation trees (v3 and v4 events), long sessions, bulk traces for list performance. Use whenever a task needs ClickHouse/Postgres test data — e.g. "seed a complex trace", "make a tough session", "fill the trace list", "test v4 events UI", or when debugging trace/session/list rendering or performance. Never write ad-hoc seed scripts or raw ClickHouse inserts.
Use when writing or reviewing Storybook stories (`.stories.tsx`) for React components.
Use when designing, implementing, reviewing, or hardening Langfuse repo-owned autonomous agents, especially GitHub Actions that invoke Claude, Codex, or another LLM agent on a schedule or workflow_dispatch, create pull requests, update workflow prompts or allowlists, handle GitHub tokens/secrets, use untrusted web content, or self-improve repo agent instructions.
MUST USE when reviewing ClickHouse schemas, queries, or configurations. Contains 28 rules that MUST be checked before providing recommendations. Always read relevant rule files and cite specific rules in responses.
Tune Langfuse infrastructure autoscaling safely across web, web-iso, and web-ingestion. Use when Codex needs to review or change Terraform scale settings, RPM targets, scale-up/scale-down boundaries, min/max task counts, cost/performance tradeoffs, dashboard scaling markers, Datadog event-loop metrics, trace/span evidence, GitHub pull requests, or Linear follow-up tickets for `web`, `web-iso`, or `web-ingestion` containers in the langfuse/infrastructure repository.