Skip to content

devto-article.md

Latest commit

 

History

History
225 lines (155 loc) · 8.53 KB

devto-article.md

File metadata and controls

225 lines (155 loc) · 8.53 KB
title I Told My AI "Never Touch Auth" — It Did Anyway. Here's How I Fixed It.
published false
description AI coding tools remember your constraints. Then ignore them. I built an open-source enforcement layer that actually stops the AI before it breaks your locked code.
tags ai, programming, beginners, discuss
cover_image

Last month, I was building a SaaS app on Bolt.new. Session 1 went great — auth system working, Supabase connected, everything clean.

Session 2, I asked Bolt to "add a dark theme."

Bolt added the dark theme. It also rewrote my auth system, switched my database queries, and broke 3 pages I didn't ask it to touch.

Sound familiar?

The Problem Nobody's Solving

AI coding tools now have memory. Claude Code has auto-memory. Cursor has Memory Bank. Lovable has Knowledge. .cursorrules and AGENTS.md exist.

But memory without enforcement is dangerous.

Here's what actually happens:

  • Your AI remembers you use Supabase — then switches to Firebase because it "seemed better"
  • Your AI remembers your auth setup — then rewrites it while "fixing" a bug
  • Your AI remembers your constraints — then ignores them when they're inconvenient

The stats back this up:

Remembering is not the same as respecting.

What I Built

I spent 6 months building SpecLock — an open-source constraint engine that adds active enforcement on top of persistent memory.

The idea is simple: you tell the AI what it can't do, and SpecLock stops it before the damage happens.

You:    "Don't ever touch the auth files"
AI:     Lock added: "Never modify auth files"

... 5 sessions later ...

You:    "Add social login to the login page"
AI:     CONFLICT (HIGH — 100%): Violates lock "Never modify auth files"
        Should I proceed or find another approach?

No other tool does this. Not Claude's native memory. Not Cursor rules. Not AGENTS.md files.

How It Works: 3 Enforcement Layers

The reason .cursorrules and AGENTS.md fail is they're suggestions. The AI reads them, then does whatever it wants. As one Cursor forum user put it: "LLMs can't guarantee 100% compliance. They work probabilistically."

SpecLock uses 3 layers that make enforcement as strong as possible:

Layer 1: Package.json Lock Sync

When you add a lock, SpecLock embeds it directly in package.json. Since every AI tool reads package.json at session start, your constraints are visible from the very first message.

{
  "speclock": {
    "active": true,
    "locks": [
      "Never modify auth files",
      "Database must always be Supabase"
    ]
  }
}

Layer 2: Semantic Conflict Detection

Before any change, SpecLock checks the proposed action against all locks. Not just keyword matching — synonym expansion (65+ groups), negation detection, and destructive action flagging:

Lock:   "No breaking changes to public API"
Action: "Remove the external endpoints"

Result: CONFLICT (85% confidence)
  - synonym match: remove/delete, external/public, endpoints/api
  - lock prohibits this action (negation detected)
  - destructive action against locked constraint

Layer 3: File-Level Guards

When you lock something like "never modify auth files", SpecLock finds the actual auth files in your project and injects a warning header:

// ============================================================
// SPECLOCK-GUARD — DO NOT MODIFY THIS FILE
// LOCKED: Never modify auth files
// THIS FILE IS LOCKED. DO NOT EDIT, CHANGE, OR REWRITE.
// A question is NOT permission. ONLY "unlock" is permission.
// ============================================================

export function Auth() { return <div>Login</div> }

When the AI opens the file to edit it, it sees the warning before it can make changes. This is the strongest layer — the AI literally has to read the guard to access the code.

Real Test: 4 Tests on Bolt.new

I ran 4 tests on Bolt.new with real locks:

Test What I Asked What Happened Result
1 "Add social media login" Bolt detected conflict with auth lock Blocked
2 "Add dark theme" Bolt added it normally Allowed (not locked)
3 "Switch database to Firebase" Bolt detected conflict with Supabase lock Blocked
4 Bolt opened Auth.tsx to edit Bolt read SPECLOCK-GUARD and refused Blocked at file level

Locked things get blocked. Unlocked things work normally. That's the whole point.

Quick Start (2 minutes)

Bolt.new / Aider / Any npm Platform

Just tell the AI:

"Install speclock and set up project memory"

Or run it yourself:

npx speclock setup --goal "Build my app"

That's it. SpecLock creates SPECLOCK.md, injects locks into package.json, and generates a context file. The AI reads these automatically.

Cursor / Claude Code / Windsurf / Cline (MCP)

Add to .cursor/mcp.json:

{
  "mcpServers": {
    "speclock": {
      "command": "npx",
      "args": ["-y", "speclock", "serve", "--project", "."]
    }
  }
}

This gives you 51 MCP tools — session memory, locks, conflict checking, git checkpoints, change tracking, constraint templates, violation reports, pre-commit hooks, and more.

Lovable (MCP Remote — No Install)

  1. Go to Settings > Connectors > New MCP server
  2. Enter URL: https://speclock-mcp-production.up.railway.app/mcp
  3. Done.

What's Different From Other Memory Tools?

Feature Claude Memory Cursor Rules AGENTS.md SpecLock
Remembers context Yes Yes Yes Yes
Blocks violations No No No Yes
Semantic conflict detection No No No Yes
File-level protection No No No Yes
Git checkpoints No No No Yes
Constraint templates No No No Yes (6 built-in)
Violation reports No No No Yes
Git pre-commit enforcement No No No Yes
Works on Bolt.new No No No Yes

New in v1.7.0: Templates, Reports, Pre-commit Hooks

SpecLock v1.7.0 adds 3 features that take enforcement to the next level:

Constraint Templates — Pre-built lock packs for popular frameworks. One command adds 5-6 locks + decisions instantly:

npx speclock setup --goal "Build my app" --template nextjs
# Applies: routing protection, API route locks, middleware guards,
# auth system lock, server component constraints + 2 architecture decisions

Available: nextjs, react, express, supabase, stripe, security-hardened

Violation Reports — Every blocked change is tracked. See stats on how many times SpecLock protected your project:

npx speclock report
# Total blocked: 12
# Most tested: "Never modify auth files" (5 blocks)

Git Pre-commit Hook — True git-level enforcement. Staged files are checked against locks before every commit:

npx speclock hook install
# Now: git commit on a guarded file → BLOCKED

The Uncomfortable Truth

Every AI coding tool will get better memory eventually. Context windows will grow. Models will improve.

But the fundamental problem remains: AI tools are optimized to be helpful, not to respect boundaries.

When you say "never touch auth" and then ask "add social login", the AI sees a conflict between your constraint and your current request — and it resolves the conflict by doing what you're currently asking. That's how LLMs work. They're people-pleasers.

The only way to fix this is an external enforcement layer that doesn't care about being helpful. It just checks the rules and blocks violations.

That's SpecLock.

Try It

Free. Open source. MIT license.

What constraint would you lock first? Drop it in the comments — I'm curious what people are most worried about their AI breaking.