# Extracting Metadata
> Use when extracting metadata from HTML — title, description, language, Open Graph, JSON-LD / Microdata / RDFa, headers, links, and images. Covers the --json output shape and the --extract-metadata flag.
- Skill: `xberg-io/extracting-metadata` (Agent Skill)
- Install (CLI): `npx skillmds@latest add xberg-io/extracting-metadata`
- Raw SKILL.md: https://api.skillmd.com/api/skills/xberg-io/extracting-metadata/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Web & Frontend
- Author: xberg-io (https://skillmd.com/u/xberg-io)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/xberg-io/extracting-metadata
---
# Extracting metadata
Use this when the user wants structured metadata out of HTML rather than (or in
addition to) the Markdown body — page title, description, language, Open Graph
tags, structured data, the heading outline, links, or image references.
Metadata lives in `result.metadata` and is surfaced on the CLI through
`--json`. On the CLI, metadata extraction is **opt-in**: pass
`--extract-metadata` alongside `--json`, otherwise `result.metadata` comes back
empty (`document.title` is null, `headers`/`links`/`images`/`structured_data`
are `[]`). The library `convert()` call extracts metadata by default
(`extract_metadata=True`) — that default is a property of the API, not the CLI.
There are no per-field extraction flags: `--extract-metadata` populates all
sub-fields below at once.
## Get all metadata
```bash
html-to-markdown --json --extract-metadata input.html | jq '.metadata'
# Extraction-only (skip the Markdown body)
html-to-markdown --json --extract-metadata --no-content input.html | jq '.metadata'
```
## Metadata sub-fields
```json
{
"metadata": {
"document": { "title": "...", "description": "...", "language": "en", "open_graph": {"title": "..."} },
"headers": [ { "level": 1, "text": "Main Heading" } ],
"links": [ { "href": "https://example.com", "link_type": "external" } ],
"images": [ { "src": "photo.jpg", "alt": "A photo", "image_type": "external" } ],
"structured_data": [ /* JSON-LD, Microdata, RDFa blocks */ ]
}
}
```
## Metadata flag
There is one metadata flag: `--extract-metadata`. With `--json` set it populates
all sub-fields above (`document`, `headers`, `links`, `images`,
`structured_data`) under `result.metadata` — select what you need with `jq`.
| Flag | Effect |
| ---- | ------ |
| `--extract-metadata` | With `--json`: populate `result.metadata`. In plain-text mode (no `--json`): prepend title + meta tags as a YAML frontmatter block (`---`-delimited) at the top of the Markdown output |
```bash
# Pull just the document-level metadata and the heading outline
html-to-markdown --json --extract-metadata --no-content input.html \
| jq '{title: .metadata.document.title, lang: .metadata.document.language, outline: [.metadata.headers[].text]}'
```
## Common queries
```bash
# Title + canonical language
html-to-markdown --json --extract-metadata input.html | jq '{title: .metadata.document.title, lang: .metadata.document.language}'
# External links only
html-to-markdown --json --extract-metadata input.html | jq '[.metadata.links[] | select(.link_type == "external") | .href]'
# Open Graph card
html-to-markdown --json --extract-metadata input.html | jq '.metadata.document.open_graph'
# JSON-LD blocks
html-to-markdown --json --extract-metadata input.html | jq '.metadata.structured_data'
```
## Programmatic access
```python
from html_to_markdown import convert
html = """
My Article
Main Heading
External link
"""
result = convert(html)
meta = result.metadata
print(meta.document.title) # "My Article"
print(meta.document.language) # "en"
print(meta.headers[0].text) # "Main Heading"
print(meta.links[0].link_type) # "external"
print(meta.images[0].alt) # "A photo"
```
Metadata is available from the single `convert()` call in Python, Rust, Go,
Ruby, and Elixir; in TypeScript read it off the returned result object. In Rust
it requires the `metadata` feature (on by default).
See `../html-to-markdown/references/cli-reference.md` (Metadata section) and
`../html-to-markdown/references/configuration.md` for field details.