The context engineering harness for AI coding agents.
Turn a fuzzy idea into a structured blueprint — story map, data model, build order, critical assumptions — then keep it in sync with your codebase as it changes. Specs that don't rot.
Hi, I'm Spec. I'll turn your idea into a living harness — not a doc that rots.
Built for Claude Code, Cursor, Codex, and the agentic SDLC.
01
Your specs were right on day one. Then your code moved on.
Most AI-planning tools hand you a stack of documents and walk away. The moment you ship your first feature, those docs are wrong — and your AI agent goes back to guessing. That's not a spec problem. It's a context problem, and it compounds every sprint.
02
Don't generate docs. Build a harness.
specstocode turns your idea into a blueprint, then wraps your AI agent in everything it needs to stay production-grade:
Instructions
A rich CLAUDE.md / AGENTS.md assembled from your project, not a static stub.
Knowledge
Story maps and docs your agent references at every step.
Memory
Decisions and an activity log that evolve with the codebase, so context never resets.
Examples
Few-shot patterns your agent reuses to match your style.
Tools & MCP registry
MCP tools for actions, resources for context — your agent reads the spec natively.
Guardrails
Complexity gates and eval stubs before risky work ships.
03
One command keeps your code and its context in sync.
$ npx specstocode init # assemble the harness from your project
$ stc next # next story, with full context loaded
$ stc done # ship it — and auto-log the decision + lesson
$ stc status # harness health at a glance
A browser extension can paste context into a chat window. It can't keep a real codebase and its context in sync over weeks. Our CLI can — that's the difference between a spec tool and a system of record.
04
Early builders ship with a harness that doesn't drift.
92%
Average harness health across active projects
First try
Agents build the right thing when context is complete
0 drift
Specs stay in sync with code, sprint after sprint
Real metrics coming soon — we're collecting data from early users.
05
Built for non-technical founders who ship with AI.
You have the idea and the drive, not a decade of architecture experience. specstocode gives your AI agent the structure a senior engineer would — so it builds the right thing, remembers why, and doesn't wander.
06
Start free. Upgrade when the harness proves its value.
Trial
7 days
£0
- ✓ 1 project
- ✓ Full agent interview
- ✓ CLI access
- ✓ Every template
- ✓ No card required
Pro
PopularMost popular
£12/mo
Billed £144/year
- ✓ Unlimited projects & stories
- ✓ specstocode CLI
- ✓ Custom spec templates
- ✓ Priority support
Team
For teams
£23/mo
Billed £276/year
- ✓ Everything in Pro
- ✓ Team workspace
- ✓ Workspace invites
- ✓ Shared spec templates
All plans include the specstocode CLI, story map canvas, and harness sync
