# What Does the `hallmark study` Command Do? Extracting Design DNA from Screenshots and URLs > Discover what the hallmark study command does. Analyze screenshots and URLs to extract design DNA like typography and color, generating a detailed report. - Repository: [Hassan El Mghari/hallmark](https://github.com/Nutlope/hallmark) - Tags: how-to-guide - Published: 2026-07-27 --- **The `hallmark study` command analyzes a user-supplied screenshot or live webpage to extract its underlying design DNA—macrostructure, archetypes, typography, and color—and returns a diagnosis report that can optionally rebuild your content or emit a portable [`design.md`](https://github.com/Nutlope/hallmark/blob/main/design.md) file.** If you want to deconstruct a website's visual system without copying pixels, the `hallmark study` command in the `Nutlope/hallmark` repository provides a structured solution. This **design-DNA extraction verb** accepts either an image file or a URL, runs safety and validation checks, and produces a detailed diagnosis report. According to the Hallmark source code, the command acts as both a learning tool for designers and a bridge to reusable design systems. ## Source-Mode Detection: URL vs. Screenshot When you invoke the tool, the skill dispatch reads the verb definition in [[`skills/hallmark/SKILL.md`](https://github.com/Nutlope/hallmark/blob/main/skills/hallmark/SKILL.md)](https://github.com/Nutlope/hallmark/blob/main/skills/hallmark/SKILL.md) at line 28. The system then auto-selects its ingestion method by inspecting the argument string. As documented in [[`skills/hallmark/references/study.md`](https://github.com/Nutlope/hallmark/blob/main/skills/hallmark/references/study.md)](https://github.com/Nutlope/hallmark/blob/main/skills/hallmark/references/study.md), the command enters **URL mode** when the argument starts with `http://` or `https://`; otherwise it assumes **image mode** and expects a screenshot file attached to the chat. ## Refusal Checks and Safety Guardrails Before any extraction begins, Hallmark runs protocol-specific safety filters. In URL mode, the system consults a **refuse list** that blocks template marketplaces, auth-walled sites, and SPA shells, then performs a remote-safety check prior to any `WebFetch` call. In image mode, a **vision pass** validates that the attached screenshot is a legitimate design reference. These refusal heuristics live in [`references/study.md`](https://github.com/Nutlope/hallmark/blob/main/references/study.md) between lines 69 and 75. ## How the `hallmark study` Command Extracts Design DNA Once the input passes validation, the pipeline extracts ten structured fields describing the source's visual grammar. In **image mode**, the vision pass captures **macrostructure**, **component archetypes**, **type-pairing**, **colour anchor**, and **rhythm**. In **URL mode**, Hallmark performs a shallow `WebFetch` of the target page and parses HTML and CSS to recover exact font names, color values, and paper or accent tokens, as implemented in [[`skills/hallmark/SKILL.md`](https://github.com/Nutlope/hallmark/blob/main/skills/hallmark/SKILL.md)](https://github.com/Nutlope/hallmark/blob/main/skills/hallmark/SKILL.md) at lines 508–512. ## Diagnosis Report and Follow-Up Actions After extraction, the command emits a one-page Markdown **diagnosis report** summarizing the captured DNA, governed by the diagnosis section in [`references/study.md`](https://github.com/Nutlope/hallmark/blob/main/references/study.md). At this point, you have three options: - **Build**: Hand the extracted DNA off to `hallmark redesign` to reconstruct your content using the studied system. - **Lock**: Emit a portable [`design.md`](https://github.com/Nutlope/hallmark/blob/main/design.md) file containing the extracted DNA for downstream tools; the specification for this file lives in [[`skills/hallmark/references/design-md.md`](https://github.com/Nutlope/hallmark/blob/main/skills/hallmark/references/design-md.md)](https://github.com/Nutlope/hallmark/blob/main/skills/hallmark/references/design-md.md). - **Stop**: End the session after receiving the diagnosis. ## `hallmark study` Command Examples Run the command against a live page by passing a URL: ```bash hallmark study https://example.com/awesome-landing-page ``` Or analyze a local screenshot: ```bash hallmark study my-favourite-portfolio.png ``` A typical response looks like this: ```markdown ## Diagnosis Report - **Macrostructure**: Marquee Hero with single-column body - **Archetypes**: Hero → Feature → Footer - **Type-pairing**: Display = Inter Tight, Body = Workbench - **Colour anchor**: Desaturated forest-green (hue ≈ 140°) - **Rhythm** (image mode): 3-step vertical flow ``` To persist the extracted DNA, run the study and then reply with the lock instruction: ```bash hallmark study https://example.com/awesome-landing-page # ... after the diagnosis, reply: lock the DNA ``` Result: a [`design.md`](https://github.com/Nutlope/hallmark/blob/main/design.md) file is emitted according to the [`design-md.md`](https://github.com/Nutlope/hallmark/blob/main/design-md.md) specification. ## Summary - The `hallmark study` command is a **design-DNA extraction verb** that reads screenshots or live URLs and returns structured design intelligence. - It auto-selects **URL mode** or **image mode** based on the argument format, then applies **refusal checks** to unsafe or invalid sources before fetching. - The extraction pipeline captures ten fields—ranging from macrostructure to color anchors—using vision passes or shallow `WebFetch` and HTML/CSS parsing. - Output is a one-page **diagnosis report**; optional follow-ups include handing off to `hallmark redesign` or emitting a portable [`design.md`](https://github.com/Nutlope/hallmark/blob/main/design.md) file. ## Frequently Asked Questions ### Can `hallmark study` clone an entire website's code? No. The command is intentionally not a code cloner. As implemented in `Nutlope/hallmark`, it captures **design DNA**—structural patterns, type scales, and color systems—and produces a diagnosis report or [`design.md`](https://github.com/Nutlope/hallmark/blob/main/design.md) spec, never a pixel-for-pixel reproduction. ### How does `hallmark study` choose between analyzing a URL and a screenshot? The verb inspects the argument string. If it starts with `http://` or `https://`, the system enters **URL mode** and performs a shallow `WebFetch`; otherwise it assumes **image mode** and validates the attached screenshot through a vision pass. This logic is documented in [`references/study.md`](https://github.com/Nutlope/hallmark/blob/main/references/study.md). ### What files govern the behavior and output of `hallmark study`? The central contract lives in [[`skills/hallmark/SKILL.md`](https://github.com/Nutlope/hallmark/blob/main/skills/hallmark/SKILL.md)](https://github.com/Nutlope/hallmark/blob/main/skills/hallmark/SKILL.md), which defines the verb syntax and high-level flow at line 28. The detailed protocol—including source-mode detection, refusal heuristics, and emission rules—is specified in [[`skills/hallmark/references/study.md`](https://github.com/Nutlope/hallmark/blob/main/skills/hallmark/references/study.md)](https://github.com/Nutlope/hallmark/blob/main/skills/hallmark/references/study.md). The portable [`design.md`](https://github.com/Nutlope/hallmark/blob/main/design.md) output format is defined in [[`skills/hallmark/references/design-md.md`](https://github.com/Nutlope/hallmark/blob/main/skills/hallmark/references/design-md.md)](https://github.com/Nutlope/hallmark/blob/main/skills/hallmark/references/design-md.md). ### Is it safe to run `hallmark study` on any public URL? No. The command enforces a **refuse list** that blocks template marketplaces, auth-walled pages, and SPA shells. A remote-safety check also runs before fetching any URL, ensuring the tool only analyzes appropriate sources.