# Microgram: dataframe-group-by

`station__algovigilance__microgram-dataframe-group-by` · native (always callable) · domain `algovigilance` · pv-relevance `pv-core`

Group rows by one or more columns and compute aggregations. Agg types: sum, mean, min, max, count, first, last, n_unique. Each agg specifies type and target column.

## Agent metadata

- `idempotent`: true
- `read_only`: true
- `expected_latency_ms`: unknown (not yet contract-tested)
- `cost_tokens_estimate`: unknown

## Input schema

- `columns` *object* (required) — Column name to array of values
- `group_cols` *object* (required) — Column names to group by
- `aggs` *object* (required) — Array of {"type": "sum"|"mean"|..., "column": "col_name"} (column omitted for count)

## Example call

```json
POST /api/mcp
Content-Type: application/json

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "station__algovigilance__microgram-dataframe-group-by",
    "arguments": {
      "columns": {},
      "group_cols": {},
      "aggs": {}
    }
  }
}
```

## Related

- [/tools](/tools) — all 7718 tools
- [/tools/algovigilance__microgram-dataframe-group-by](/tools/algovigilance__microgram-dataframe-group-by) — HTML page
- [/tools/algovigilance__microgram-dataframe-group-by/json](/tools/algovigilance__microgram-dataframe-group-by/json) — JSON form (agent-friendly)
- [/api/mcp](/api/mcp) — endpoint
- [/AGENTS.md](/AGENTS.md) — agent guide