fortify

A design-review rule set for handling real-world conditions outside the ideal user journey. It covers errors, empty screens, loading, first use, slow connections, older devices, unusual input, and other edge cases.

In plain words
What is it for?
It helps review and design error recovery, empty and loading states, first-run experiences, stress cases, and readiness for different languages and devices.
Why use it?
It prevents products from only working when users have perfect conditions and make no mistakes.

Cursor rule for Cursor

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 rules/ghaida/intent/fortify
Clone the repo
git clone --depth 1 https://github.com/ghaida/intent

Made for: Cursor.

Per session 157 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 4,636 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 $0.00157 $0.04636
Opus 5 $0.00078 $0.02318
Sonnet 5 $0.00031 $0.00927
Haiku 4.5 $0.00016 $0.00464

Measured 2d ago against content hash 506ff9566bab, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

fortify 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 2d 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.

.cursor/rules/fortify.mdc · 244 lines

How it starts

The opening of the file, as written. The whole thing — 244 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Fortify — Harden for Real-World Use

Overview

The happy path is a fantasy. Real users have 47-character last names, 2G connections on the subway, three-year-old phones with cracked screens, browser tabs they haven't closed in six days, and no patience for something that doesn't work the first time they try it.

Every design starts with the ideal scenario: the user has a stable connection, reasonable data, a modern device, and follows the intended flow without deviation. That scenario accounts for maybe 60% of actual usage. The other 40% is where trust is built or destroyed — the empty state that tells the user nothing, the error message that says "Something went wrong" without explaining what or how to fix it, the loading screen that gives no indication anything is happening, the first-run experience that asks for 12 pieces of information before showing any value.

Fortify systematically identifies every condition your users will actually encounter and ensures the design handles each one with the same care you gave the happy path. This isn't about pessimism — it's about respect for the people using what you build.

When to activate this skill: Edge case reviews, error state design, empty state design, loading pattern design, first-run experience design, offline mode planning, internationalization readiness checks, stress testing, or any moment someone asks "but what happens when..."


Skill family

Fortify works alongside the full Intent skill system, with especially tight connections to skills that define the paths you stress-test:

  • /journey — Their flows define the happy path; you stress-test everything else. Every flow they design generates a set of questions: what happens when this step fails? What if the user abandons midway and returns? What if data from step 2 isn't available at step 4? Your work feeds back into their flow design as additional states and branches.

  • /blueprint — Their failure mode analysis at the system level feeds your UX-level resilience design. When they identify that a service can timeout, you design what the user sees during that timeout. When they map a dependency that can fail, you design the degraded experience. System-level failure modes become UX-level state designs.

Read the full file on GitHub · 244 lines

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. 2d ago First seen · 244 lines · 4,636 tokens per session scan A 506ff9566bab

Subscribe to this mod's changes

fortify is a cursor rule published in the GitHub repository ghaida/intent (139 stars, last pushed 1mo ago), licensed CC0-1.0. It adds 157 tokens to every session and 4,636 once invoked, about $0.0008 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.