## link

```bash
mercemur link --store acme.mercemur.com
```

Writes `.mercemur.json` so every command in this directory knows which store it acts on, **after
checking** that the store answers and the key works.

The check is the point. Writing a config that turns out to be wrong moves the failure to the next
command, where the message is about that command rather than about the link.

## env pull

```bash
mercemur env pull
mercemur env pull --force   # replace values already set
```

Fills `.env.local` with what the CLI can prove: the store id, the API base, the storefront URL and
the default locale.

<Warning>
  **It cannot supply a publishable key.** Keys are minted from the dashboard and are not on the
  public API, so the file records the variable with a note rather than leaving a name you discover
  from a stack trace. Run `mercemur open apikeys`.
</Warning>

Existing values are kept unless you pass `--force`: a local override is usually deliberate.
Unrelated variables and key order are preserved, so a pull is a small diff rather than a rewrite.

## translations

```bash
mercemur translations locales
mercemur translations export -o strings.csv
mercemur translations export -o fr.csv --locale fr --resource-type product
mercemur translations import strings.csv --dry-run
mercemur translations import strings.csv
```

Columns are `locale, resource_type, resource_id, field, value`, with the value last because it is
the only one a translator edits.

<Note>
  The API scopes a translation list to **one resource** on purpose, so an export walks them and
  reports how many reads that took. A store with ten thousand products should see what the export
  costs before it is surprised by it. Reading `product` requires `read_products`, and so on for
  each type walked.
</Note>

Import sends only the values that **differ**, so re-importing an unchanged export writes nothing.
Leading and trailing space is preserved: it belongs to the translator, and stripping it changes the
rendered copy.

## redirects

```bash
mercemur redirects export -o redirects.csv
mercemur redirects import redirects.csv --dry-run
mercemur redirects import redirects.csv
```

Columns are `from_path, to_path, status_code`. A status must be 301, 302, 307 or 308; anything else
is refused rather than guessed at.

<Warning>
  **Import only adds and updates.** A redirect missing from the file is left alone, because a
  shorter file is far more often a partial export than an instruction to delete the rest, and
  removing a live redirect breaks a URL somebody has indexed.
</Warning>

A file that redirects the same path twice is refused, naming both rows: that is a merge accident,
and applying both silently leaves whichever landed last.

## seo

```bash
mercemur seo list
mercemur seo audit
```

`audit` reports the mistakes a search result makes visible: a duplicate title across two pages, a
description too long to survive truncation, one too short to say anything.

It audits **what is set**, not what is missing. A resource with no override falls back to its own
catalogue title, which is usually correct, and reporting every one of those would bury the findings
that matter.

Exits non-zero on a duplicate title, which is the one finding here that is unambiguously wrong: two
pages competing for the same query is a decision nobody made. Length findings are warnings, because
those limits are conventions that move.

## metafields

```bash
mercemur metafields definitions
mercemur metafields export -o metafields.jsonl
mercemur metafields import metafields.jsonl --dry-run
mercemur metafields import metafields.jsonl
```

One JSON object per line, not CSV.

<Warning>
  **A metafield's value is typed by its definition**: a number, a boolean, an object, a list of
  references. CSV stringifies all of it, so `420` comes back as `"420"` and nothing reports it
  until a template renders the quotes. JSONL keeps the type and still gives a diff of one line per
  field.
</Warning>

Values are compared as **canonical JSON**, so the same object with its keys in another order is
the same value and a reformatted file is not mistaken for a store-wide edit.

A line with no `definition_id` is refused rather than guessed at: the definition is what decides
the value's type, and writing one without it stores a shape the storefront cannot read. Run
`mercemur metafields definitions` to see them.

A malformed line names its own line number, because "invalid character" in a file of several
thousand is a search rather than a fix.

## A header with no rows

Every import here treats a header-only CSV as zero rows rather than an error. That file is exactly
what an export of a store with none of these produces, and erroring on it would break the round
trip at its emptiest point. A file with no header at all names no columns and is refused.