read-file

What the source does

• FilesystemNone observedNo reads or writes in the source
• NetworkNone observedNo outbound calls in the source
• ShellNone observedNo commands run in the source
• DependenciesPinnedNothing floats
• SecretsNone foundNo keys in source

Five audit layers

Gates applied: no behavioural pass.

Audit 0.4.1 · source sha eaf479591fd1 · 26 Oct 2026Report an issue or request a re-scan

• Publisherduckdb GitHub organizationOwner of the repository this skill is read from
• Source folderduckdb/duckdb-skills/skills/read-fileThe exact folder we audited
• LicenceMITAs the repository states it
• Commit pinned for this verdicteaf479591fd1A new audit runs when the source changes
• Repository statusNot archivedLast push 185 days ago
• Sandboxed runNot runSkills are read, not executed; layer L4 is skipped

Its description: Read any data file (CSV, JSON, Parquet, Avro, Excel, spatial, SQLite) or remote URL (S3, HTTPS). Use when user references a data file, asks "what's in this file", or wants to preview/profile a dataset. Not for source…

---
name: read-file
description: >
  Read any data file (CSV, JSON, Parquet, Avro, Excel, spatial, SQLite) or remote URL (S3, HTTPS).
  Use when user references a data file, asks "what's in this file", or wants to preview/profile a dataset.
  Not for source code.
argument-hint: <filename or URL> [question about the data]
allowed-tools: Bash
---

You are helping the user read and analyze a data file using DuckDB.

Filename given: `$0`
Question: `${1:-describe the data}`

## Step 1 — Read it

`RESOLVED_PATH` is `$0`. If the user gave a bare filename (no `/`), resolve it to a full path with `find` first.

Run a single DuckDB command that defines the `read_any` macro inline and reads the file.

For **remote files**, prepend the necessary LOAD/SECRET before the macro:

| Protocol | Prepend |
|---|---|
| `https://` / `http://` | `LOAD httpfs;` |
| `s3://` | `LOAD httpfs; CREATE SECRET (TYPE S3, PROVIDER credential_chain);` |
| `gs://` / `gcs://` | `LOAD httpfs; CREATE SECRET (TYPE GCS, PROVIDER credential_chain);` |
| `az://` / `azure://` / `abfss://` | `LOAD httpfs; LOAD azure; CREATE SECRET (TYPE AZURE, PROVIDER credential_chain);` |

For **local files**, no prefix needed.

```bash
duckdb -csv -c "
CREATE OR REPLACE MACRO read_any(file_name) AS TABLE
  WITH json_case AS (FROM read_json_auto(file_name))
     , csv_case AS (FROM read_csv(file_name))
     , parquet_case AS (FROM read_parquet(file_name))
     , avro_case AS (FROM read_avro(file_name))
     , blob_case AS (FROM read_blob(file_name))
     , spatial_case AS (FROM st_read(file_name))
     , excel_case AS (FROM read_xlsx(file_name))
     , sqlite_case AS (FROM sqlite_scan(file_name, (SELECT name FROM sqlite_master(file_name) LIMIT 1)))
     , ipynb_case AS (
         WITH nb AS (FROM read_json_auto(file_name))
         SELECT cell_idx, cell.cell_type,
                array_to_string(cell.source, '') AS source,
                cell.execution_count
         FROM nb, UNNEST(cells) WITH ORDINALITY AS t(cell, cell_idx)
         ORDER BY cell_idx
     )
  FROM query_table(
    CASE
      WHEN file_name ILIKE '%.json' OR file_name ILIKE '%.jsonl' OR file_name ILIKE '%.ndjson' OR file_name ILIKE '%.geojson' OR file_name ILIKE '%.geojsonl' OR file_name ILIKE '%.har' THEN 'json_case'
      WHEN file_name ILIKE '%.csv' OR file_name ILIKE '%.tsv' OR file_name ILIKE '%.tab' OR file_name ILIKE '%.txt' THEN 'csv_case'
      WHEN file_name ILIKE '%.parquet' OR file_name ILIKE '%.pq' THEN 'parquet_case'
      WHEN file_name ILIKE '%.avro' THEN 'avro_case'
      WHEN file_name ILIKE '%.xlsx' OR file_name ILIKE '%.xls' THEN 'excel_case'
      WHEN file_name ILIKE '%.shp' OR file_name ILIKE '%.gpkg' OR file_name ILIKE '%.fgb' OR file_name ILIKE '%.kml' THEN 'spatial_case'
      WHEN file_name ILIKE '%.ipynb' THEN 'ipynb_case'
      WHEN file_name ILIKE '%.db' OR file_name ILIKE '%.sqlite' OR file_name ILIKE '%.sqlite3' THEN 'sqlite_case'
      ELSE 'blob_case'
    END
  );

DESCRIBE FROM read_any('RESOLVED_PATH');
SELECT count(*) AS row_count FROM read_any('RESOLVED_PATH');
FROM read_any('RESOLVED_PATH') LIMIT 20;
"
```

**If this fails:**
- **`duckdb: command not found`** → invoke `/duckdb-skills:install-duckdb` and retry.
- **Missing extension** (e.g. spatial files, xlsx, sqlite) → retry with `INSTALL spatial; LOAD spatial;` or `INSTALL sqlite_scanner; LOAD sqlite_scanner;` prepended before the macro.
- **Wrong reader / parse error** → use the correct `read_*` function directly instead of `read_any`.

## Step 2 — Answer

Using the schema, row count, and sample rows, answer:

`${1:-describe the data: summarize column types, row count, and any notable patterns.}`

Excerpt, first 3,664 characters of SKILL.md, verbatim from the audited commit. It is text from someone else’s repository, quoted so you can judge it before your agent reads it.

git clone https://github.com/duckdb/duckdb-skills
git -C duckdb-skills checkout eaf479591fd1

Works in

1. 2026-10-26
   ✓SAFE B 89 / 100

   first audit · source eaf479591fd1

Questions about read-file

• github.com/duckdb/duckdb-skills/tree/main/skills/read-file — the audited source at commit eaf479591fd1 and every finding aboveObserved · 26 Oct 2026

Spotted something wrong? Report a correction · Methodology