Join two lists of JSON rows on a key, like SQL or VLOOKUP: left, inner, full, anti joins, union.
Scored across 2 tools
join_rows performs data joins and list_capabilities retrieves server metadata; their purposes are completely distinct with no overlap. An agent can easily select the right tool based on the task.
Both tool names follow a consistent verb_noun pattern (join_rows, list_capabilities) using snake_case. This predictable convention makes the set easy to scan and understand.
The server is narrowly scoped to dataset joining, so 2 tools is not unreasonable. The single join_rows tool efficiently covers all join types and options, with list_capabilities as a necessary discovery companion, though the set is slightly thin compared to typical multi-tool servers.
join_rows supports all standard join types (left, inner, full, leftAnti, rightAnti, union) plus key matching, conflict strategies, and fan-out modes, leaving few gaps. Minor operations like previewing or validating data without joining are absent, but the core domain is well covered.
Joins two lists of JSON rows on a shared key, like a SQL join or a spreadsheet VLOOKUP, and returns the combined rows plus a summary: how many rows matched on each side, match rates, and warnings for duplicate keys, rows missing the key and key fields that exist on no row. Use it to enrich a list with fields from a lookup table (left join), keep only the overlap (inner), combine two sources into one table (full), find rows in one list that are missing from the other (leftAnti or rightAnti), or stack two same-shape lists (union). Keys match case-insensitively with whitespace trimmed by default, and the key can have a different name on each side (email on the left, contact_email on the right). Input and output rows are capped per call; a many-to-many join that would exceed the output cap is refused with the predicted row count, never truncated. Call list_capabilities for the exact limits.
Inputs: leftRows (required), rightRows (required), joinType, keyMatching, +7 more.
Returns every join type, key matching mode, conflict strategy and fan-out mode this server supports, the fields it adds to each row, and the input and output row limits per call. Free, processes no data.
Inputs: no named parameters.
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Returns two Apify datasets, files or Google Sheets by URL, or JSON arrays joined on key fields...
Compare two versions of a JSON row list: what was added, removed or changed, field by field.
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Add one secure layer between your agents and this server.