mcpbeat

Establishing Code Ownership

posthog/establishing-code-ownership

Determine which PostHog team owns a file, directory, or code path, or enumerate all code a team owns (via distributed `owners.yaml`, `products/*/product.yaml`, and `.github/CODEOWNERS`). Use when assigning a reviewer, attributing a bug or slow query to a team, routing work, scoping a team-wide audit, or answering "who owns X" / "what does team Y own".

1k tokens
context cost
the whole folder, loaded on every use
1
files
instructions only
0
copies elsewhere
how many repositories repackaged it
690
stars on the repo
on the repository, not the skill itself

Install

one command, takes just this skill from the repository
npx skills add https://github.com/PostHog/posthog --skill establishing-code-ownership

The instruction itself

7 sections, as written by the author

Establishing code ownership

Ownership is resolved by one tool — hogli owners:* — over distributed owners.yaml files.

Don't re-parse the ownership files by hand; the resolver owns the semantics and is what CI enforces.

Fast path: hogli owners:*

Dev machines have flox/hogli, so shell straight to the resolver.

hogli owners:who posthog/hogql/printer.py    # who owns this path (+ the file that decided it)
hogli owners:resolve --json posthog/api/survey.py products/surveys/backend/api.py   # batch, JSON keyed by path
hogli owners:unowned                          # every tracked file with no owner (append a prefix to scope: `owners:unowned products/`)

owners:who prints the resolved owners, the status, the Slack channel, and source — the owners.yaml/product.yaml file that decided the answer.

The channel comes from the root teams: registry entry for the primary owner, else a derived #<slug>; a path whose primary owner is an @handle has no channel.

owners:resolve takes paths as arguments or newline-delimited on stdin, so you can pipe a file list: git ls-files posthog/hogql | hogli owners:resolve --json.

No hogli/flox available? The dependency-light fallback needs only pyyaml: git ls-files posthog/hogql | PYTHONPATH=tools/owners python -m posthog_owners (stdin paths → the same JSON).

Resolution algorithm (what the resolver does)

For a path, it walks from the repo root down to the path collecting ownership files, then merges them nearest-file-wins:

  • owners.yaml — the canonical, distributed source. Each directory can carry one. Fields (owners, status, inherit, per-path rules) fall through to the nearest ancestor unless overridden. inherit: false cuts the walk (Gerrit's set noparent) — nothing above it contributes. Within a file, rules: are last-match-wins. owners: null means unowned by design (exempt from the coverage check), distinct from a directory with no file at all (genuinely unowned).
  • products/<name>/product.yaml — an accepted alias. When a product dir has no owners.yaml, its product.yaml owners: list is read as the ownership for products/<name>/** (every other product.yaml field is ignored). A dir with both files is a lint error; owners.yaml wins.
  • .github/CODEOWNERS — blocking approvals, never part of the walk. It keeps GitHub-native semantics, stays hand-maintained (mostly infra, e.g. team-security), and is enforced by GitHub itself. The resolver does not read it — when you need to know whether a blocking approval is additionally required, consult the file directly. It never changes the resolved owners, and nothing here writes to it.

Owners are a mixed list of team slugs (team-devex, conversations, logs — the GitHub team handle minus @PostHog/) and @handles for individuals; the first entry is the primary owner.

team → code (what does this team own?)

There's no single "team → files" command; resolve the tree and filter by slug:

git ls-files | hogli owners:resolve --json | jq -r 'to_entries[] | select(.value.owners | index("team-surveys")) | .key'

Also grep products/*/product.yaml for the slug — each hit is all of that products/<name>/**; one team often owns several, so don't stop at the first.

Owned paths span backend and frontend/src/...; cover both, or say up front you're doing one side.

Generated files

A generated artifact often resolves to a broad parent owner or nobody.

Trace it to the input it's generated from and report that team as the logical owner (e.g. services/mcp/src/tools/generated/<x>.ts comes from products/<name>/mcp/tools.yaml).

Distinguish the logical owner (the team owning the source — the answer to report) from the literal resolver result on the generated path, and flag the gap so the operator can decide whether to pin it with a rules: entry.

Last resort: feature-ownership handbook, then Slack

If neither the resolver nor product.yaml resolves it, consult the feature-ownership handbook — coarse-grained (broad areas, not files) and hand-maintained, so prefer the repo files and flag any handbook-sourced answer as possibly stale.

If even that fails and the Slack MCP is available, search Slack — least authoritative (opinions, stale threads), so verify against the repo files and flag the answer as Slack-sourced.

Slug vs handle

  • Handle (CODEOWNERS): @PostHog/<slug>, e.g. @PostHog/team-replay.
  • Slug (owners.yaml / product.yaml): handle minus @PostHog/, e.g. team-replay.
  • Not uniform: some carry team- (team-self-driving), some don't (conversations, logs). If a name doesn't resolve, try both forms.

How to use it

Copy the folder

Take posthog/establishing-code-ownership from the repository into ~/.claude/skills for personal use, or into .claude/skills inside a project.

Check the name does not clash

The agent identifies a skill by the name field in its header. Two skills with the same name cannot sit side by side — one of them will be ignored.