convert-file
Convert any data file to another format: CSV, Parquet, JSON, Excel, GeoJSON, and more. Use when the user says "convert to parquet", "save as xlsx", "export as JSON", "make this a CSV", "turn into parquet", or any variation of format-to-format conversion for data files. Also triggers when the user wants to write Parquet, Excel, or other binary formats that Claude cannot produce natively.
What this skill does
You are helping the user convert a data file from one format to another using DuckDB.
Input file: `$0`
Output file: `${1:-}`
## Step 1 — Resolve input and output
**Input**: `$0`. If it's a bare filename (no `/`), resolve to a full path with `find "$PWD" -name "$0" -not -path '*/.git/*' 2>/dev/null | head -1`.
**Output**: If `$1` is provided, use it as the output path. If not, default to the same stem as the input with a `.parquet` extension (e.g., `data.csv` → `data.parquet`).
Infer the output format from the output file extension:
| Extension | Format clause |
|---|---|
| `.parquet`, `.pq` | *(default, no clause needed)* |
| `.csv` | `(FORMAT csv, HEADER)` |
| `.tsv` | `(FORMAT csv, HEADER, DELIMITER '\t')` |
| `.json` | `(FORMAT json, ARRAY true)` |
| `.jsonl`, `.ndjson` | `(FORMAT json, ARRAY false)` |
| `.xlsx` | `(FORMAT xlsx)` — requires `INSTALL excel; LOAD excel;` |
| `.geojson` | `(FORMAT GDAL, DRIVER 'GeoJSON')` — requires `LOAD spatial;` |
| `.gpkg` | `(FORMAT GDAL, DRIVER 'GPKG')` — requires `LOAD spatial;` |
| `.shp` | `(FORMAT GDAL, DRIVER 'ESRI Shapefile')` — requires `LOAD spatial;` |
## Step 2 — Convert
Run a single DuckDB command. Prepend extension loads as needed based on both the input and output formats.
```bash
duckdb -c "
<EXTENSION_LOADS>
COPY (FROM '<INPUT_PATH>') TO '<OUTPUT_PATH>' <FORMAT_CLAUSE>;
"
```
For remote inputs (`s3://`, `https://`, etc.), prepend the same protocol setup as `read-file`:
| Protocol | Prepend |
|---|---|
| `s3://` | `LOAD httpfs; CREATE SECRET (TYPE S3, PROVIDER credential_chain);` |
| `gs://` / `gcs://` | `LOAD httpfs; CREATE SECRET (TYPE GCS, PROVIDER credential_chain);` |
| `https://` / `http://` | `LOAD httpfs;` |
**If the user mentions partitioning** (e.g., "partition by year"), add `PARTITION_BY (col)` to the format clause. This only works with Parquet and CSV output.
**If the user mentions compression** (e.g., "use zstd"), add `CODEC 'zstd'` for Parquet output.
## Step 3 — Report
On success, report:
- Input file and detected format
- Output file, format, and size (`ls -lh`)
- Row count if quick to compute
On failure:
- **`duckdb: command not found`** → delegate to `/duckdb-skills:install-duckdb`
- **Missing extension** → install it and retry
- **Input parse error** → suggest the user check the input format or try `/duckdb-skills:read-file` first to inspect it
Related in Ads & Marketing
ads
IncludedMulti-platform paid advertising audit and optimization skill. Analyzes Google, Meta, YouTube, LinkedIn, TikTok, Microsoft, and Apple Ads. 250+ checks with scoring, parallel agents, industry templates, and AI creative generation.
banana
IncludedAI image generation Creative Director powered by Google Gemini Nano Banana models. Use this skill for ANY request involving image creation, editing, visual asset production, or creative direction. Triggers on: generate an image, create a photo, edit this picture, design a logo, make a banner, visual for my anything, and all /banana commands. Handles text-to-image, image editing, multi-turn creative sessions, batch workflows, and brand presets.
rpg-migration-analyzer
IncludedAnalyzes legacy RPG (Report Program Generator) programs from AS/400 and IBM i systems for migration to modern Java applications. Extracts business logic from RPG III/IV/ILE source code, identifies data structures (D-specs), file operations (F-specs), program dependencies (CALLB/CALLP), and converts RPG constructs to Java equivalents. Generates migration reports, complexity estimates, and Java implementation strategies with POJO classes, JPA entities, and service methods. Use when modernizing AS/400 or IBM i legacy systems, analyzing RPG source files (.rpg, .rpgle, .RPGLE), converting RPG to Java, mapping data specifications to Java classes, planning legacy system migration, or when user mentions RPG analysis, Report Program Generator, RPG III/IV/ILE, AS/400 modernization, IBM i migration, packed decimal conversion, or mainframe application rewrite.
brand-library-architect
IncludedBuild a complete brand library for a product — visual asset render pipeline, brand documentation set (BRAND, COPY, MANIFESTO, BIOS, FAQ, GLOSSARY, TONE, PRICING), open-source convention files (README, CONTRIBUTING, SECURITY, CODE_OF_CONDUCT), and a self-contained press kit. This skill should be used when the user asks to "build a brand library / brand kit / press kit / brand assets" for a product, "set up a brand library workflow," "create a positioning manifesto plus visual identity," or any combination of brand documentation + visual asset pipeline. Apply phase-by-phase or run end-to-end. Templates are product-agnostic and use {{TOKEN}} placeholders the skill prompts the user to fill.
writing-tech-post
IncludedAuthors engineering blog posts end-to-end: launch deep-dives, incident postmortems, architecture migrations, performance case studies, tutorials, AI/agent system writeups, security disclosures, and research-to-product translations. Picks the correct archetype, plans the abstraction ladder, enforces an evidence cadence (diagrams, benchmarks, profiles, traces, code, ablations), tunes voice against publisher house styles (Datadog, Vercel, GitHub, AWS, Meta, Cloudflare, Jane Street), and runs a pre-publish gate for narrative momentum and disclosure ethics. Use when drafting a new engineering post, restructuring a draft that feels flat, deciding which evidence form belongs where, validating that depth and product context are balanced, or preparing a postmortem, migration, or performance narrative for external publication. Do not use for API reference documentation, README authoring, marketing copy, release notes, generic SEO content, ghost-written executive thought leadership, or non-engineering long-form essays.
blog-google
IncludedGoogle API integration for blog performance: PageSpeed Insights, CrUX Core Web Vitals with 25-week history, Search Console performance, URL Inspection, Indexing API, GA4 organic traffic, NLP entity analysis for E-E-A-T, YouTube video search for embedding, and Google Ads Keyword Planner. Progressive feature availability based on credential tier (API key, OAuth/service account, GA4, Ads). Shares config with claude-seo at ~/.config/claude-seo/google-api.json. Use when user says "google data", "page speed", "core web vitals", "search console", "indexation", "GA4", "keyword research", "nlp entities", "blog performance", "youtube search", "google api setup".