SpecSpace
Authoring layer for spec-driven development

Spec-prompts that carry their own expertise.

Compose modular, forkable spec sections for your AI coding agent. Every section ships with the examples, pitfalls, and acceptance criteria that spare your agent the wrong turns someone already took — not just a description of what to build.

Feeds Spec Kit, Kiro & OpenSpec — it doesn't replace them.
section: auth/session · depth: rigorous · guidance: 2 pitfalls, 3 acceptance criteria · forked from marketplace/auth-core
Composes intoSpec KitKiroOpenSpecClaude CodeCursorspecspace is where the spec is written — export it wherever you build.
The atomic unit

A Section is three layers, not a blob of text.

Most prompt libraries hand your agent a paragraph and hope. A SpecSpace Section separates the shape from the substance from the expertise — so each part can be reused, checked, and improved on its own.

Schema

The shape it must take

A typed contract for the section — fields, depth profile, and what it depends on. Composable and machine-checkable.

Content

What to actually do

The concrete instruction your agent reads — written once, refined over time, reusable across every project that needs it.

GuidanceThe moat

Why it goes right

Worked examples, known pitfalls, and acceptance criteria for judging the result — expertise that travels with the section instead of living in someone's head.

Why SpecSpace

More than a prompt library.

A prompt library hands your agent text. SpecSpace hands it structured, reusable expertise — and the composition tools to shape it into exactly the spec each build needs. Each capability below is labeled honestly: live now, or on the roadmap.

2.1

Fork, merge & split

Live

Adapt a section without touching the original, reconcile two that overlap, or break up one that outgrew its scope — composition at section granularity.

forkmergesplit
2.2

Depth profiles

Live

One section at three resolutions — lite · standard · rigorous. A quick prototype and a production build draw from the same source of truth.

2.3

Templates that stay current

Live

Bundle sections into ordered templates. Improve a section once and every template built on it inherits the change — no copy-paste drift.

2.4

A marketplace, not a blank page

Live

Start from community sections instead of an empty prompt. Publish your own, and let the guidance compound as others fork and refine it.

2.5

Export anywhere, no lock-in

Live

Author here, build where you already do — export into Spec Kit, Kiro, OpenSpec, Claude Code, or Cursor. SpecSpace owns the authoring, never your workflow.

2.6

Security-pack modules

Roadmap

In development: drop-in sections for the parts that bite — auth, access control, session handling, input validation — with the known pitfalls written in before the agent starts.

How it works

From blank prompt to a spec your agent follows.

STEP 1

Pick or fork sections

Start from the marketplace or your own library. Fork anything to fit your stack and conventions — the guidance comes with it.

STEP 2

Compose a template

Order the sections, set the depth profile, and let each section's examples, pitfalls, and acceptance criteria travel along.

STEP 3

Export & build

Hand the result to Claude Code, Cursor, or Spec Kit. The agent gets the expertise, not just the ask.

Install in Claude Code

Specspace, running inside Claude Code.

One install brings the catalog and the compose skill into the agent you already use. The MCP server is wired to the Specspace API, so sections, guidance, and saved specs flow without leaving the session.

$claude plugin install https://github.com/TAESTUDIOS/specspaceclaudecode

Adds the plugin and its MCP server. Sections stream from specspace.io — no local catalog to keep in sync.

>approve the sign-in

The first run opens a browser. Approve with your Specspace (GitHub) sign-in — you never paste a token.

>“compose a spec for a next.js auth module”

The skill lists sections, reads each one's guidance, fills the fields, and saves the spec to your account.

Also runs in OpenAI Codex — the same MCP server, installed with a one-line ./install.sh. Early access: both plugin repos are private during pre-release, so request access from Specspace before installing.

For teams

Start solo. Scale to a shared canon.

One source of spec truth for the whole team.

When your team adopts it, shared workspaces keep everyone composing from the same sections — with roles deciding who can edit the canon.

Shared section libraries
Owner / admin / member roles
Private team workspaces
Pricing

Start free. Upgrade when it earns it.

Free
$0
Compose and ship public specs, end to end.
  • Public sections & templates
  • Fork, merge & split
  • Marketplace access
Sign in with GitHub
Pro Coming soon
$—/mo
Private specs and the full export toolkit for serious solo work.
  • Everything in Free
  • Private sections & templates
  • CLI / API & multi-format export
Join early access
Team
Per seat
Shared workspaces for teams composing from one canon.
  • Everything in Pro
  • Shared team libraries
  • Roles & access controls
Join the waitlist

Stop re-explaining the same thing to every agent.

Write the section once, with the guidance that makes it land — then compose it into everything you build.