CLI

One binary, fsl, with four commands. Run it with npx fsl <command>.

npx fsl help

fsl help, fsl --help or -h after any command prints the usage text and exits 0. An unknown command prints it and exits 1. The CLI loads .env.local from the current folder first.

fsl upload-sourcemaps

npx fsl upload-sourcemaps --backend=./functions --embed-sourcemaps
npx fsl upload-sourcemaps --backend=./functions --embed-sourcemaps --bucket=my-maps --prefix=fsl-maps
npx fsl upload-sourcemaps --bucket= --backend=./backend --embed-sourcemaps

Uploads .map files from dist/ to Cloud Storage and deletes them locally. Run it in your deploy script, between the build and the deploy. See Source maps.

Flag	Meaning
--bucket=<name>	The bucket. Defaults to VITE_FIREBASE_STORAGE_BUCKET, then FIREBASE_STORAGE_BUCKET. An empty --bucket= means no bucket, whatever those two hold.
--backend=<path>	The backend folder, such as ./functions or ./backend. --functions is a deprecated alias.
--embed-sourcemaps	Copy the maps to {backend}/sourcemaps/current/ for fast lookup of the current release.
--release=<id>	The release id. Defaults to VITE_RELEASE_ID, then RELEASE_ID. With none of them set, it exits 1.
--dist=<path>	The build folder to read maps from. Defaults to ./dist.
--prefix=<path>	The Storage prefix to upload under. Defaults to sourcemaps/.

Maps are stored at gs://<bucket>/sourcemaps/<releaseId>/<filename>.map. The prefix must match sourceMaps: { prefix } on the log function, or maps are not found.

With --embed-sourcemaps and no bucket, it embeds the current release and uploads nothing. Only the deployed release can then be resolved. With neither a bucket nor --embed-sourcemaps, it prints usage and exits 1. If the upload fails but the maps were embedded, it exits 3.

It authenticates with FIREBASE_SERVICE_ACCOUNT_PATH when set, otherwise with application-default credentials.

fsl doctor

npx fsl doctor
npx fsl doctor --backend=./server --dist=./dist
npx fsl doctor --strict --json

Checks the setup from disk, with no network and no credentials. It reads firebase.json when present. See fsl doctor.

Flag	Meaning
--backend=<path>	The backend folder, when there is no firebase.json.
--dist=<path>	The web build folder, when there is no firebase.json.
--strict	Fail on warnings as well as errors.
--json	Print JSON instead of the report.

Exit code 0 with no errors, 1 with an error, or with a warning under --strict.

fsl logs

npx fsl logs --where labels.userId=<uid> --since 2h
npx fsl logs schema
npx fsl logs attachments <logId>

Reads production logs through gcloud logging read, or .fsl-logs/*.jsonl with --local. One JSON entry per line. See fsl logs.

Flag	Meaning
--where field=value	A condition, repeatable. Operators =, !=, >=, <=, ~.
--select a,b,count	Fields to print. With no value, lists the fields.
--group-by field	Aggregate per value.
--order-by "field desc"	Sort order.
--limit N	100 by default, 1000 at most.
--distinct field	Distinct values of a field.
--since 1h	30m, 1h, 2d or an ISO time. 1 hour by default.
--repeats <repeatKey>	One repeating error, with its true count.
--local	Read .fsl-logs/ instead of Cloud Logging.
--project <id>	The project. Read from .firebaserc when not given.

fsl logs schema

Flag	Meaning
--refresh	Re-read the logs. --add entries are kept.
--add name [meaning]	Record a label your code can write. Repeatable.
--remove name	Drop a label recorded with --add. Repeatable.
--json	Print JSON.
--local	Read the local files.
--project <id>	The project.

fsl logs attachments

npx fsl logs attachments <logId> --bucket <name>

Downloads an entry’s files to .fsl-logs/attachments/<logId>/ through gcloud storage. The bucket is --bucket <name>, else FIREBASE_STORAGE_BUCKET, else VITE_FIREBASE_STORAGE_BUCKET. --project <id> names the project.

fsl install-skills

npx fsl install-skills
npx fsl install-skills --global --force

Copies the package’s skills to .claude/skills/, or ~/.claude/skills/ with --global. It prompts before overwriting, and before removing a skill the package no longer ships (logs, query-logs). --force skips the prompts. With no terminal to answer on and no --force, it asks nothing, installs what needs no answer, lists on stderr what it left, and exits 1. See Skills for coding agents.