Find Google Play Console Credentials

<objective> `gpc auth login` needs a **Google service-account JSON key**, a **Play Console app/package**, and **Play Console permissions** for that service-account email. This skill finds or creates the JSON, stores it in the repo-ignored NowStack path, and verifies that `gpc` can access `dev.melvynx.nowstack`.

Key insight from the NowStack Android setup: this is a two-console credential. Google Cloud owns the service account and JSON key; Google Play Console owns app access. A Cloud project alone is not enough. The service-account email must be invited in Play Console -> Users and permissions with app-scoped release permissions.

Terminology: gpc here means the Google Play Console CLI used by this repo. gcp means Google Cloud Platform, where the service account is created. </objective>

<nowstack_state> Known NowStack values:

Value	Current value
Android package	dev.melvynx.nowstack
Runtime credential path	mobile-app/google-play-service-account.json
Git ignore status	mobile-app/google-play-service-account.json is ignored
Android deploy skill	.agents/skills/ns-deploy-android-app/SKILL.md
Observed download candidate	~/Downloads/play-publisher-500306-d28739223973.json

Treat observed downloads as candidates only. Verify JSON structure before using them. </nowstack_state>

<credentials_anatomy>

Credential	What it looks like	Where it lives
Service-account JSON	JSON with type: "service_account", project_id, private_key_id, private_key, client_email	User disk; Downloads first, then repo ignored runtime path
Client email	<name>@<project-id>.iam.gserviceaccount.com	Inside the JSON; this is what Play Console must invite
Cloud project ID	e.g. play-publisher-500306	Inside the JSON; API must be enabled here
Android package	dev.melvynx.nowstack	site-config.ts > androidPackage, Expo android.package, Play Console app
Developer ID	long numeric ID in Play Console URLs	Optional; useful for debugging account selection

Look-alikes that are NOT Play publishing credentials:

• google-services.json - Firebase client config, not an API private key.
• Android keystore files (.jks, .keystore) - signing credentials, not Play API auth.
• App Store Connect .p8 files - iOS only.
• OAuth client secrets - not the default credential for gpc/Fastlane server-side uploads. </credentials_anatomy>

<step n="1" title="Check if gpc already works">

From the repo root:

command -v gpc && gpc --version
export GPC_APP="dev.melvynx.nowstack"
test -f mobile-app/google-play-service-account.json && export GPC_SERVICE_ACCOUNT="$PWD/mobile-app/google-play-service-account.json"
gpc doctor || true
gpc status || true

If gpc doctor and a read-only gpc status work for dev.melvynx.nowstack, stop. The credential is already usable. </step>

<step n="2" title="Hunt for service-account JSON files">

Search standard locations first. Use jq to avoid mistaking random JSON files for credentials:

find "$HOME/Downloads" "$HOME/Desktop" "$HOME/Documents" "$HOME/Developer" "$HOME/.config/gcloud" \
  -maxdepth 6 -type f -name "*.json" -size -2M 2>/dev/null |
while IFS= read -r file; do
  jq -e '
    .type == "service_account"
    and (.client_email | test("@.*\\.iam\\.gserviceaccount\\.com$"))
    and (.private_key | startswith("-----BEGIN PRIVATE KEY-----"))
  ' "$file" >/dev/null 2>&1 || continue

  jq -r --arg file "$file" '
    "\($file)\tproject=\(.project_id)\temail=\(.client_email)\tkey_id=\((.private_key_id // "")[0:8])..."
  ' "$file"
done

Do not print .private_key. Do not paste the JSON into chat. File path, project ID, and client email are enough for debugging. </step>

<step n="3" title="If no JSON exists, create/download one">

Use the official shape: create/select a Google Cloud project, enable the Google Play Android Developer API, create a service account, create a JSON key, then grant the service-account email access in Play Console.

If the user sees a Google Cloud project selector with "Nouveau projet" and no obvious "linked project", that is normal enough. Create or select a dedicated Cloud project for Play publishing. Do not burn time looking for a hidden linked-project list. The real access gate is:

1. androidpublisher.googleapis.com enabled on the Cloud project.
2. Service account JSON key downloaded.
3. Service-account email invited in Play Console -> Users and permissions.

Manual console path:

Google Cloud Console -> IAM & Admin -> Service Accounts
Google Cloud Console -> APIs & Services -> Library -> Google Play Android Developer API -> Enable
Play Console -> Users and permissions -> Invite new user

CLI path when gcloud is already authenticated and the user has chosen {project_id}:

gcloud config set project "{project_id}"
gcloud services enable androidpublisher.googleapis.com
gcloud iam service-accounts create play-publisher --display-name "NowStack Play Publisher"
gcloud iam service-accounts keys create "$HOME/Downloads/nowstack-play-publisher.json" \
  --iam-account "play-publisher@{project_id}.iam.gserviceaccount.com"

The downloaded JSON key is a secret. It can be recreated later by creating another key, but this exact private key is only shown/downloaded at creation time. </step>

<step n="4" title="Grant Play Console permissions">

Open Play Console as the account owner/admin and invite the service-account email from the JSON:

jq -r .client_email mobile-app/google-play-service-account.json

Grant app-scoped access to the NowStack app/package dev.melvynx.nowstack. Minimum practical permissions depend on the target flow:

• Internal/closed testing upload: grant the permissions needed to view app information, manage testing tracks, and release apps to testing tracks.
• Production rollout: also grant release-to-production permissions.
• Listing/screenshots automation: grant store presence/listing permissions.
• Billing/purchase verification: grant the financial/orders/subscriptions permissions required by the Google Play Developer API.

Prefer app-scoped permissions over full account admin. Use account-level admin only if the release automation truly needs broad access and the user explicitly accepts it. </step>

<step n="5" title="Organize the JSON">

Keep the canonical runtime path in the repo-ignored file that existing NowStack skills expect:

mkdir -p "$HOME/Developer/google-play"

# Replace the source path with the verified candidate JSON.
install -m 600 "/path/to/verified-service-account.json" \
  "$HOME/Developer/google-play/nowstack-play-service-account.json"

ln -sf "$HOME/Developer/google-play/nowstack-play-service-account.json" \
  mobile-app/google-play-service-account.json

chmod 600 "$HOME/Developer/google-play/nowstack-play-service-account.json"

If the verified JSON is still in ~/Downloads, move it out of Downloads after setup so future agents do not pick an old duplicate. </step>

<step n="6" title="Validate locally and with gpc">

First validate the file shape without exposing secrets:

export GPC_APP="dev.melvynx.nowstack"
export GPC_SERVICE_ACCOUNT="$PWD/mobile-app/google-play-service-account.json"

jq -e '
  .type == "service_account"
  and (.client_email | test("@.*\\.iam\\.gserviceaccount\\.com$"))
  and (.private_key | startswith("-----BEGIN PRIVATE KEY-----"))
  and (.project_id | length > 0)
' "$GPC_SERVICE_ACCOUNT" >/dev/null

jq -r '"project=\(.project_id)\nemail=\(.client_email)\nkey_id=\((.private_key_id // "")[0:8])..."' "$GPC_SERVICE_ACCOUNT"

Then authenticate and verify read-only Play access:

gpc auth login --service-account "$GPC_SERVICE_ACCOUNT"
gpc doctor
gpc status

If gpc is unavailable or blocked, validate with Fastlane as a fallback:

bundle exec fastlane run validate_play_store_json_key json_key:"$GPC_SERVICE_ACCOUNT"

After this skill succeeds, Android upload/promotion belongs to ns-deploy-android-app, ns-android-beta, or ns-android-distribute. </step>

<step n="7" title="Persist non-secret findings">

Record only non-secret operational facts in AGENTS.md, release notes, or agent memory:

• Credential runtime path: mobile-app/google-play-service-account.json.
• Canonical local archive path: ~/Developer/google-play/nowstack-play-service-account.json.
• Package name: dev.melvynx.nowstack.
• Cloud project ID.
• Service-account client email.
• Play Console permission scope: app-scoped vs account-wide, testing vs production/listing/billing.
• Verification result: gpc doctor and gpc status worked on the expected package.

Never record the private key, full JSON contents, or any copied secret material. </step>

<failure_modes>

• jq finds google-services.json: wrong file; Firebase client config cannot authenticate Play publishing.
• gpc doctor says auth is missing: GPC_SERVICE_ACCOUNT path is wrong, the JSON is malformed, or gpc auth login has not been run.
• gpc/Fastlane says API has not been used or is disabled: enable androidpublisher.googleapis.com on the JSON's project_id.
• The caller does not have permission: the service-account email was not invited to Play Console, lacks app access, or lacks release/listing/billing permissions.
• Package not found: the Play Console app for dev.melvynx.nowstack does not exist in that developer account, or the service account lacks access to that app.
• Project selector confusion: use a Cloud project plus Play Console Users and permissions; do not require a visible "linked project" row before creating the service account.
• Duplicate JSON files: verify the active one by client_email, project_id, and gpc status; do not keep stale Downloads copies around. </failure_modes>

<critical_safety>

• Never commit service-account JSON, keystores, passwords, .env secrets, or App Store .p8 files.
• Never paste or print .private_key.
• Do not run upload, publish, promote, or listing mutation commands from this skill. This skill only finds/authenticates credentials and performs read-only verification.
• Do not try to automate the user's Google login or bypass 2-Step Verification. Ask the user to complete browser-only Play Console permission grants.
• Before any later real Play mutation, run validate-only/dry-run commands and get explicit user confirmation of package, account, track, service account, release notes, and artifact. </critical_safety>

<references> - Official Google Play Developer API setup: https://developers.google.com/android-publisher/getting_started - Play Console users and permissions: https://support.google.com/googleplay/android-developer/answer/9844686 - Play release permissions/testing tracks: https://support.google.com/googleplay/android-developer/answer/9859348 </references>

<success_criteria>

• A valid service-account JSON is stored behind mobile-app/google-play-service-account.json.
• GPC_SERVICE_ACCOUNT points to that file and GPC_APP=dev.melvynx.nowstack.
• The service-account email is invited in Play Console with the needed app permissions.
• gpc doctor succeeds.
• gpc status can read the expected NowStack Play app/package.
• No secret material is committed, printed, or copied into docs. </success_criteria>