fidelity

fidelity is a command for coding agents from Manavarya09/design-extract. It costs 40 tokens per session (466 once invoked), scanned A, original, MIT.

A website comparison command that scores how closely a clone matches the original, from visual appearance to animation behaviour. It produces an overall score, letter grade and ordered list of fixes.

In plain words
What is it for?
Use it to compare an original URL with a cloned or locally running page, inspect pixel-difference images, review motion differences and create a shareable score card.
Why use it?
It replaces subjective claims such as “pixel-perfect” with measured differences. Developers can see which visual or motion problems should be fixed first.

Command

Part of the designlang plugin — 2 skills, 14 commands shipped together

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add commands/manavarya09/design-extract/fidelity
Clone the repo
git clone --depth 1 https://github.com/Manavarya09/design-extract

Or install designlang, the plugin that ships this one along with the rest of its 2 skills, 14 commands.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for fidelity

README.md
[![agentmods](https://agentmods.dev/badge/commands/manavarya09/design-extract/fidelity.svg)](https://agentmods.dev/commands/manavarya09/design-extract/fidelity)
Your own site
<a href="https://agentmods.dev/commands/manavarya09/design-extract/fidelity"><img src="https://agentmods.dev/badge/commands/manavarya09/design-extract/fidelity.svg" alt="Measured on agentmods" height="20"></a>
Per session 40 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 466 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00040 $0.00466
Opus 5 $0.00020 $0.00233
Sonnet 5 $0.00008 $0.00093
Haiku 4.5 $0.00004 $0.00047

Measured 4d ago against content hash e7850910618b, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

fidelity scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

commands/fidelity.md · 43 lines

What it actually says

Run designlang fidelity to score a clone against the site it was cloned from. Unlike tools that just hand you code and claim "pixel-perfect", this measures it: a full-page pixel-diff for visuals and a motion-fidelity comparison (durations, easings, springs, keyframe kinds, scroll-linked motion, choreography/stagger) — blended into one score with a ranked plan of what to fix next.

npx designlang fidelity $ARGUMENTS

If no $ARGUMENTS were supplied, ask the user for the original URL and the clone URL (often a local dev server like http://localhost:3000).

After the run, surface the overall score + grade, the visual/motion split, and the top correction directives. Outputs land in the output dir:

File What it is
fidelity.md headline score, motion breakdown table, ranked correction plan
fidelity.json the full machine-readable report
fidelity-card.svg a shareable score card (88% · B · stripe.com)
fidelity-diff.png the visual loss heatmap

Useful flags via $ARGUMENTS:

Flag Effect
--clone <url> the clone to score (required)
--min <score> exit non-zero if overall fidelity is below this (CI gate)
--motion-runtime capture real runtime motion + choreography on both sides

This is the self-correcting clone loop: measure → read the correction plan → rebuild → re-run until the score crosses your threshold. Pair with /extract and /verify.

Full reference: https://github.com/Manavarya09/design-extract#full-cli-reference

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 4d ago First seen · 43 lines · 40 tokens per session scan A e7850910618b

Subscribe to this mod's changes

fidelity is a command published in the GitHub repository Manavarya09/design-extract (4,000 stars, last pushed 4d ago), licensed MIT. It adds 40 tokens to every session and 466 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.