wren-query

Installation
SKILL.md

The user wants to run a Wren CLI command. $ARGUMENTS is the SQL query or instruction.

What to do

  1. Check for ~/.wren/mdl.json and ~/.wren/connection_info.json using Read or Glob.

    • If either is missing, tell the user what's needed and show the format below.
    • If both exist, proceed directly.
  2. Run the appropriate command based on what the user asked:

Intent Command
Execute and return results uv run wren --sql '...'
Translate to native SQL (no DB) uv run wren dry-plan --sql '...'
Validate without fetching rows uv run wren dry-run --sql '...'
Check SQL is valid uv run wren validate --sql '...'

If wren is installed globally (not via uv), use wren directly instead of uv run wren.

  1. Show the result and explain what happened.

Required files

Both files are auto-discovered from ~/.wren/.

mdl.json — semantic model

{
  "catalog": "wren",
  "schema": "public",
  "models": [
    {
      "name": "orders",
      "tableReference": { "schema": "mydb", "table": "orders" },
      "columns": [
        { "name": "order_id",  "type": "integer" },
        { "name": "total",     "type": "double" },
        { "name": "status",    "type": "varchar" }
      ],
      "primaryKey": "order_id"
    }
  ]
}

connection_info.json — connection info (include datasource field)

{
  "datasource": "mysql",
  "host": "localhost",
  "port": 3306,
  "database": "mydb",
  "user": "root",
  "password": "secret"
}

Supported datasource values: mysql, postgres, bigquery, snowflake, clickhouse, trino, mssql, databricks, redshift, oracle, duckdb.


Override flags

When needed, flags can override the defaults:

wren --sql '...' --mdl other-mdl.json --connection-file prod-connection_info.json
wren --sql '...' --output csv          # table (default) | csv | json
wren --sql '...' --limit 100

Common errors

Error Fix
mdl.json not found Create ~/.wren/mdl.json
connection_info.json not found Create ~/.wren/connection_info.json with a datasource field
datasource key not found Add "datasource": "mysql" to connection_info.json
unknown datasource 'X' Check spelling; see supported values above
Connection refused Confirm the DB is running and host/port are correct
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Installs
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GitHub Stars
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First Seen
Apr 7, 2026