A simple program to check for errors in a JSON stream.

Reads a stream of JSON values, one per line, from standard input. (This format is variously known as line delimited JSON (ldjson), newline delimited JSON (ndjson), or JSON lines (jsonl).) When a line cannot be parsed as valid JSON, prints a description of the parse error, followed by the erroneous line with some context (previous four lines and next line, if any).

Built for investigating T276643, but may also be useful elsewhere.

Published under the GNU Affero General Public License, version 3 or later.