sealed_pool_build errors with "Bulk metadata missing 'download_uri'"

[chidniu]

Area

Draft/limited workflows

Description

sealed_pool_build doesn't work.

Steps to Reproduce

1. Ask the assistant to rate a card pool.
2. Make sure it uses sealed_pool_build.

Expected Behavior

sealed_pool_build works.

Actual Behavior

It errors with:

Error
sealed_pool_build failed: Bulk metadata missing 'download_uri'. Keys: ['object', 'id', 'type', 'updated_at', 'uri', 'name', 'description', 'jsonl_download_uri', 'compressed_size']

mtg-mcp-server version

FastMCP Horizon (hosted)

Transport

FastMCP Horizon (hosted)

MCP Client

Claude Web

[joaocarmo]

Scryfall changed the bulk data API. See Updates to Bulk Data and /cards Deprecation Notice. The download_uri key is gone. It is now jsonl_download_uri, and the format changed from a JSON array to gzipped JSONL.

This breaks every tool that uses bulk data, not only sealed_pool_build but also deck_analysis, deck_validate and the bulk_* tools. Hosted and local installs are probably both affected.

There are three separate problems and fixing only the first gives the next error:

1. ensure_loaded reads download_uri, which no longer exists
2. The file is gzipped and served as content-type: application/gzip with no content-encoding header, so httpx does not decompress it and _parse then fails with a UnicodeDecodeError
3. The content is JSONL (one card per line), not a JSON array, so json.loads on the whole file fails

The fix should be something like:

# ensure_loaded
download_url = metadata.get("jsonl_download_uri") or metadata.get("download_uri")

# _parse
if raw_bytes[:2] == b"\x1f\x8b":
    raw_bytes = gzip.decompress(raw_bytes)

if raw_bytes.lstrip()[:1] == b"[":
    raw = json.loads(raw_bytes)
else:
    raw = [json.loads(line) for line in raw_bytes.splitlines() if line.strip()]

And keeping the old paths as a fallback means both formats still work.