Posthog Desktop Skill for Claude

Working in products/desktop

products/desktop/ is the PostHog desktop app (Electron + agent framework), imported from

PostHog/code and kept as a nested standalone workspace: own pnpm-workspace.yaml, own

lockfile, own Biome config, Node 22. It is excluded from the root pnpm-workspace.yaml, from

ruff/mypy, from root Jest, from oxlint/oxfmt, from stylelint and from pytest.

**Read products/desktop/AGENTS.md before writing code

in this tree.** It is the source of truth for architecture, layer boundaries, DI, and style.

This skill only covers the scoping contract around it.

Scope contract

Default: everything you read, edit, run and test lives under products/desktop/. Run all

commands with that as cwd. Do not go fishing in frontend/, posthog/, or other products/*

for patterns — the desktop tree has its own, and copying monorepo idioms in is a defect.

Step outside only when one of these is true:

• The user explicitly tells you to.
• A backend API the app calls needs to change. The client is

packages/api-client/; the endpoints it hits live in the Django monorepo (see below).

• Desktop CI / config that lives at the root by design. The list is fixed — see

products/desktop/MIGRATION.md "Root-repo changes (outside products/desktop/)":

.github/workflows/desktop-*.yml, .github/actions/desktop-*/,

.github/scripts/products/desktop/, and the exclusion entries in pnpm-workspace.yaml,

pyproject.toml, pytest.ini, package.json (lint:css), frontend/jest.config.ts,

.dockerignore, .oxlintrc.json, .oxfmtrc.json, .config/.markdownlint-cli2.jsonc,

.github/workflows/ci-{frontend,storybook,backend}.yml (+ .depot/workflows/ci-backend.yml).

Touch these only to keep an exclusion correct; say so when you do.

Anything else outside the tree: stop and ask.

Toolchain — root CLAUDE.md does not apply here

| Root monorepo says | In products/desktop use |

| ----------------------------------------------------- | ------------------------------------------------------------- |

| ruff / mypy / pytest | nothing — no Python app code here |

| oxlint + Oxfmt, pnpm --filter=@posthog/frontend fix | pnpm lint (Biome check --write), pnpm format |

| Jest, hogli test | Vitest (pnpm test), Playwright (pnpm test:e2e) |

| pnpm --filter=@posthog/frontend typescript:check | pnpm typecheck (turbo, all packages) |

| Kea logics, typegen:write | Zustand stores + InversifyJS services; no kea, no typegen |

| LemonUI in frontend/ and products/*/frontend/ | @posthog/quill + Tailwind + Radix Themes |

| hogli build:openapi → generated frontend types | packages/api-client/src/generated.ts (hand-maintained here) |

| 4-space / repo Prettier habits | Biome, 2-space, double quotes |

Commands (from products/desktop/): pnpm install, pnpm dev, pnpm build, pnpm typecheck,

pnpm lint, pnpm test, pnpm test:e2e, pnpm --filter <pkg> <task>,

node scripts/check-host-boundaries.mjs.

Never run root-level pnpm install expecting it to cover desktop, and never let a desktop

dependency change alter the root lockfile — the root install must stay byte-identical.

What still applies from the root

• Conventional commits and PR titles; scope of desktop (e.g. fix(desktop/$feature): ...).
• .github/pull_request_template.md structure, including the Agent context section.
• Public-repo copy safety: no customer names, internal incidents, or Slack quotes.
• Merging: gh pr merge <number> --squash into master. **AGENTS.md "Merging PRs" and

products/desktop/.claude/skills/merging-prs/ are stale** — they describe the PostHog/code

Trunk queue against main, which does not exist here. products/desktop/POST-MIGRATION.md

has the correct flow.

• hogli ci:preflight on push (pre-push hook) still runs repo-wide.

Cross-boundary: the Django API

packages/api-client/ calls monorepo endpoints — tasks (/api/projects/:id/tasks/...),

signals, agent applications, environments/MCP installations, /api/users/. When a change needs

the backend:

• Read the Django side to get the contract right; that is in scope without asking.
• Editing it is a separate, monorepo-side change: root CLAUDE.md rules apply again

(/improving-drf-endpoints, /django-migrations, serializer help_text, hogli build:openapi).

• Keep the two sides in one PR only if they must ship together; otherwise land the backend first.
• Wiring the app at a local Django instance (OAuth app, RSA keys, flags) is

products/desktop/docs/LOCAL-DEVELOPMENT.md.

Resync hazard

The tree is a verbatim copy of PostHog/code at a pinned SHA. A resync replaces it wholesale, so

edits to imported files are lost unless they are upstreamed or listed as intentional drift.

Before changing a file, consider whether the fix belongs upstream in PostHog/code. The drift

list, the local security patches that must be reapplied, and the monorepo-only files

(MIGRATION.md, POST-MIGRATION.md, product.yaml, docs/plan.md) are in

products/desktop/MIGRATION.md. Do not delete or "clean up" monorepo-only files.

Desktop-local skills

products/desktop/.claude/skills/ ships its own: test-electron-app (drive the running app

over CDP :9222), quill-code, storybook-stories, canvas-templates, merging-prs (stale,

see above). Prefer these over monorepo equivalents while in this tree.

Before reporting done

• pnpm typecheck and pnpm lint from products/desktop/, plus pnpm test for touched packages.
• After touching packages/core: biome lint packages/core, zero noRestrictedImports.
• After touching @posthog/platform: rebuild or typecheck its dist/.
• After moving logic out of apps/code: node scripts/check-host-boundaries.mjs --prune.
• Confirm the diff touches nothing outside products/desktop/ — or name what it touches and why.