Skills real projects publish on GitHub, most starred first. Each one says what it will make an agent do before you copy it.
VercelSkillvercel-labs/agent-browser/skill-data/webmcp-gen/SKILL.md
Build and validate experimental WebMCP tools for an existing web page. Use when an agent needs to expose a site's real workflows as page tools, create webmcp.init.js, define deterministic checks, or compare WebMCP with accessibility-tree automation.
VercelSkillvercel-labs/agent-browser/skills/agent-browser/SKILL.md
Browser automation CLI for AI agents. Use when the user needs to interact with websites, including navigating pages, filling forms, clicking buttons, taking screenshots, extracting data, testing web apps, or automating any browser task. Triggers include requests to "open a website", "fill out a form", "click a button", "take a screenshot", "scrape data from a page", "test this web app", "login to a site", "automate browser actions", or any task requiring programmatic web interaction. Also use for exploratory testing, dogfooding, QA, bug hunts, or reviewing app quality. Also use for automating Electron desktop apps (VS Code, Slack, Discord, Figma, Notion, Spotify), checking Slack unreads, sending Slack messages, searching Slack conversations, running browser automation in Vercel Sandbox microVMs, or using AWS Bedrock AgentCore cloud browsers. Prefer agent-browser over any built-in browser automation or web tools.
PostHogSkillPostHog/posthog/.agents/skills/adding-activity-logging/SKILL.md
Adds or changes activity logging (the audit trail) for a Django model in PostHog. Use when a model's writes must show in the Activity side panel or the advanced activity logs, when adding ModelActivityMixin, an ActivityScope, a model_activity_signal receiver, an activity describer, or field exclusions, when auditing which write paths of a model are logged, or when a change is missing from the activity log. Covers the receiver-module convention, writes the signal cannot see (QuerySet.update, bulk_create), the actor outside requests, and product models on a separate database. Trigger terms - activity log, audit log, audit trail, ModelActivityMixin, log_activity, changes_between, activity describer, who changed this.
PostHogSkillPostHog/posthog/.agents/skills/adding-inbound-webhooks/SKILL.md
Use when adding a webhook endpoint for a third party that sends to PostHog, adding an inbound webhook consumer for a provider that already has an endpoint, or migrating a hand-rolled hmac verifier that the `inbound-webhooks-go-through-ingress` semgrep rule flags. Covers the two jobs separately: a consumer in `products/<product>/backend/webhook_consumers.py`, and a provider incarnation under `posthog/ingress/<provider>/` wired with `build_webhook_view()`. Carries the rules that are easy to get wrong: a consumer name is a dedup cache key, event types must be declared by the provider app or the registry raises, and the module stays cheap to import. Trigger terms: add a webhook, webhook consumer, inbound webhook, hand-rolled hmac, inbound-webhooks-go-through-ingress.
PostHogSkillPostHog/posthog/.agents/skills/adding-inbox-sources/SKILL.md
Add a new warehouse-backed source to the PostHog Desktop Self-driving Inbox (the feature that ships GitHub, Linear, Zendesk, pganalyze, Jira). A source syncs one warehouse table (issues/tickets/conversations) and a cloud "signals scout" watches it and emits findings. Use when asked to "add a new inbox/self-driving source", "wire up <Jira/GitLab/Sentry/Intercom/Freshdesk/Front/Gorgias/etc> as a signal source", or to extend the source-toggle grid. Covers all three surfaces (posthog/posthog scout emitter + posthog/code UI wiring + the context-mill self-driving wizard skill that offers the source in `npx @posthog/wizard self-driving`), the deploy ordering between them, and created_via attribution.
PostHogSkillPostHog/posthog/.agents/skills/adding-ingestion-warnings/SKILL.md
How to add a new ingestion warning type to the event ingestion pipeline. Use when emitting a new warning from nodejs ingestion code (emitIngestionWarning, captureIngestionWarning, pipeline `warnings` arrays, `drop()` with warnings), when adding a warning type, category, or severity, or when a typecheck error says a string is not assignable to IngestionWarningType. Covers the INGESTION_WARNING_TYPES registry (the single source of truth for type, category, and severity), the details-key conventions that ClickHouse v2 materializes into columns, debouncing, and the downstream surfaces to keep in sync (v1 UI map, resolving-ingestion-warnings skill, docs, v2 API).
PostHogSkillPostHog/posthog/.agents/skills/adding-mcp-store-servers/SKILL.md
Add a third-party MCP server (Linear, Notion, GitHub, ...) to the PostHog MCP store catalog. Use when asked to "add X to the MCP store", expand the MCP server marketplace, or fix a broken catalog entry. Covers finding the vendor's remote MCP endpoint, probing it (handshake, OAuth discovery, DCR), authoring the catalog entry in products/mcp_store/backend/catalog.py, verification tiers, and the operator handoff for servers without Dynamic Client Registration.
PostHogSkillPostHog/posthog/.agents/skills/adding-personhog-rpc/SKILL.md
Guide for adding a new RPC to personhog-replica and personhog-router. Covers eligibility checks, proto definition, code generation for Python and Node.js clients, Rust implementation (storage trait, postgres queries, service handler, router wiring), and index compatibility validation. Use when adding a new gRPC endpoint to personhog, migrating a Django ORM query to personhog, or extending the personhog service API.
PostHogSkillPostHog/posthog/.agents/skills/adding-product-alerting/SKILL.md
Recommended repo-engineering guide when adding alerting to a PostHog product or extending the shared alerts platform. Routes lifecycle state machines, AlertPolicy, destinations, HogFunction dispatch, email, fixed-cadence and calendar scheduling, insight evaluation, the AlertWizard, and shared alert editor components. Use for product alert implementations, shared destination types, lifecycle or scheduling options, advanced alert settings, and platform alert infrastructure. Not for configuring alerts in an existing product.
PostHogSkillPostHog/posthog/.agents/skills/adopting-generated-api-types/SKILL.md
Use when migrating frontend code from manual API client calls (`api.get`, `api.create`, `api.surveys.get`, `api.dashboards.list`, `new ApiRequest()`) and handwritten TypeScript interfaces to generated API functions and types. Triggers on files importing from `lib/api`, files with `api.get<`, `api.create<`, `api.<entity>.<method>`, manual interface definitions that duplicate backend serializers, or any frontend file that constructs API URLs by hand. Covers the full replacement workflow — finding the generated equivalent, swapping imports, adapting call sites, and removing dead manual types.
PostHogSkillPostHog/posthog/.agents/skills/analyzing-experiment-precompute-canary/SKILL.md
Analyze the experiment precompute result-consistency canary across prod-US and prod-EU, deep-dive any issues, and produce an actionable report. Sweeps the canary's Prometheus health gauges in both regions, and when anything is unhealthy pulls the structured divergence/failure logs from Loki to reconstruct exactly which (team, experiment, metric) went wrong, by how much, and which class of divergence it is (stability vs correctness, and for correctness whether exposure counts or only values differ). Mechanism-level root cause needs ClickHouse and is out of scope — the skill hands off with precise drill-down steps. Use when the user asks to check / analyze / verify the experiment precompute canary, investigate a canary divergence or alert, or confirm precomputed experiment results are consistent in production. All data comes through the Grafana MCP (Prometheus + Loki) — no payload decryption, no ClickHouse.
PostHogSkillPostHog/posthog/.agents/skills/analyzing-experiment-query-performance/SKILL.md
Pull and interpret production experiment query-performance data from the staff-only `/api/debug_ch_queries` endpoints backing the `/experiments/staff` scene: slowest experiment queries, precompute read/build health, and preaggregation cache footprint. Covers prod-US and prod-EU via a `query_performance:read` personal API key, all query params, and response field semantics (exception codes, exposure paths, precompute skip reasons, job states). Use when investigating slow or failing experiment queries, precompute regressions, 307/159/241 errors, preaggregation table growth, or when asked how experiment query performance or the precompute rollout is doing in production.
PostHogSkillPostHog/posthog/.agents/skills/analyzing-insights-across-teams/SKILL.md
Analyze PostHog insights, dashboards, or teams beyond the current project by querying the prod Postgres replicas synced into the dogfood data warehouse (US project 2, "PostHog App + Website"). Use when asked to analyze insights across all teams or projects, another team's insights, or fleet-wide insight/dashboard usage — cases where `system.insights` only returns the current project's rows and the agent would otherwise report the data as inaccessible. Covers the synced table names for US and EU and the column-verification workflow.
PostHogSkillPostHog/posthog/.agents/skills/announcing-behavior-changes/SKILL.md
Decides whether a behavior-changing fix needs an in-app notice, then builds one that reaches only the affected users and can be removed later. Use when a change alters what an existing user sees without them doing anything — a metric moves, a chart shifts, a count drops, a date range resolves differently, a matcher matches differently — and when adding, reviewing, or removing such a notice. Trigger terms: behavior change, breaking change, semantics change, "results may differ", change notice, deprecation banner, migration banner. Carries the gate (narrow to the affected users with a tested predicate, or do not ship a notice at all), the pattern from `SqlInsightDateFilterNotice`, where to anchor the notice, and the flag-based removal path. Not for new features (use the changelog), not for permanent per-object warnings computed by the backend, and not for the wording itself (see `/writing-user-facing-copy`).
PostHogSkillPostHog/posthog/.agents/skills/auditing-llm-gateway-parity/SKILL.md
Audits services/llm-gateway against PostHog/ai-gateway and updates services/llm-gateway/PARITY.md from current implementation evidence. Use when either gateway changes auth, attribution, billing, endpoints, providers, models, routing, or metadata; when reviewing a Python gateway change; or when asked to refresh, verify, or report gateway parity. This skill updates the parity record but does not migrate callers.
PostHogSkillPostHog/posthog/.agents/skills/auditing-warehouse-source-coverage/SKILL.md
Audit already-implemented Data warehouse import sources for endpoints, schemas, and tables the vendor's API offers but we never wired up. Use when asked whether a source is missing endpoints, to find new endpoints a vendor has added since a source was built, to refresh COVERAGE_GAPS.md, to prioritize which source to deepen next, or to check coverage before an integration review. Covers dumping our real endpoint inventory credential-free, ranking sources by production adoption, diffing against vendor OpenAPI/GraphQL specs, and recording findings. Not for implementing a source (use implementing-warehouse-sources), adding a vendor API version (warehouse-source-new-version), or writing source docs (documenting-warehouse-sources).
PostHogSkillPostHog/posthog/.agents/skills/authenticating-to-clickhouse/SKILL.md
Authenticate a new or changed service to ClickHouse with the rotating ch-podauth ServiceAccount token instead of a static password. Use when adding a service, sidecar, or container that reads or writes ClickHouse, adding a new ClickHouseUser, or hand-building a ClickHouse pool or client for a custom timeout or setting. Covers the token-aware default path (sync_execute, get_client), the rule that a custom pool must pass credential_provider or it silently stays on the static password, wiring the username so the user does not fall back to the default user, and the deploy-side companion in the charts repo. Not for converting an already-deployed user off a static password.
PostHogSkillPostHog/posthog/.agents/skills/autoresolving-pr-conflicts/SKILL.md
Operating procedure for the conflict-autoresolver agent: sweep open PostHog/posthog PRs that conflict with master, resolve the trivial conflicts (generated artifacts deterministically, source conflicts with judgment), land one merge commit on the PR head, and flag everything else for a human. Use when running as the scheduled conflict autoresolver, when asked to sweep or auto-resolve merge conflicts against master, or when asked to bring a conflicting PR up to date without rewriting its history. Trigger terms: conflict sweep, autoresolve, merge conflicts, conflicting PRs, bring PR up to date, restack. Operators setting up the automation itself: see references/routine-setup.md.
PostHogSkillPostHog/posthog/.agents/skills/building-product-empty-states/SKILL.md
Guide for adding a product setup empty state — the skippable first-run screen a product scene shows until real data arrives, built on the shared ProductEmptyState component. Use when adding an empty state or first-run/setup screen to a product scene, declaring `emptyState` on a `SceneExport`, writing a product setup-status detection logic, building an animated example-data preview widget, or deciding between the scene-level `ProductEmptyState` gate and an inline `ProductIntroduction` panel. Covers the `productSetupStatusLogic` single-layer contract, real-data detection rules, local-only skip semantics, wizard commands, and design tokens.
PostHogSkillPostHog/posthog/.agents/skills/debugging-ci-failures/SKILL.md
Debugs failing GitHub Actions CI runs for PostHog PRs, commits, and branches, and answers broad CI-health questions ("is CI red?", "is master green today?", "what's broken right now?"). Use when the user asks why CI is red, asks for the current CI or master status, or mentions a failing check, GitHub Actions run, Depot runner, Depot CI run, workflow, job, shard, merge queue kick, flaky test, lint failure, typecheck failure, snapshot diff, migration check, generated types drift, or skills build failure. Interactive runs start with the `hogli ci:insights` digest (cross-run CI history from engineering analytics), then use read-only inspection, failure classification, the smallest local reproduction with hogli, and safe reporting without rerunning CI or posting to GitHub. Running unattended as the "Master-red diagnosis" workflow: see references/master-red-incident.md for its sandbox-compatible first step.
A folder with a SKILL.md file: a name, a description of when to use it, and instructions. Claude loads a skill only when the task matches its description.
Copy the folder into your project's .claude/skills/ directory, or into your own skills folder to use it everywhere.
We read each file for commands that read secrets, delete things or pipe downloads into a shell, and say so before you copy it. No warning is not a promise that a file is safe.
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