Features

Everything the Kit installs so your project never drifts.

A deterministic SDLC, a token-lean memory layer, nine slash commands, and the structural guarantees that hold it all together.

Deterministic SDLC

A spec-first pipeline that refuses to skip steps.

Every feature runs through six ordered steps. The plan won’t generate while the SRS has open questions in load-bearing categories - structure is enforced, not suggested.

Requirements gate blocks code without a frozen spec

6 steps: requirements → architecting → product → tech → plan → build

Every override is logged in design-decisions.md

/spec-feature
  1 requirements  ✓
  2 architecting  ✓
  3 product-spec  ✓
  4 tech-spec     ✓
  5 planning      ✓
  6 writing-code  ▶

The memory layer

Condensed memory, written once, read forever.

Re-reading source to reconstruct intent is a token tax. The Kit writes append-only memory files and reads a compressed snapshot instead of re-scanning the repo.

CLAUDE.md + context.md stay under 8k tokens

Append-only logs for features and decisions

/spec-sync compresses any file past 1,500 lines

claude/
  context.md          state
  srs.md              frozen
  plan.md             8-10 steps
  features.md         append-only
  design-decisions.md append-only
  learnings.md        append-only

Structure that compounds

A canonical tree every skill and human can navigate.

A predictable layout means agents and people always know where to look. The Kit scaffolds it in under five seconds with lint-clean defaults.

Same tree on npm and PyPI - never drifts

Resumable workflows if interrupted

Three-way merge on upgrade - never clobbers your edits

npx spec-init my-app

├─ claude/
├─ design/
├─ CLAUDE.md
├─ CHANGELOG.md
└─ README.md

✓ ready in 4.2s

Nine slash commands

One command for every move you make.

/spec-init

Scaffold the project inside an existing Claude session.

/spec-requirements

Build claude/srs.md via cross-questioning.

/spec-design

Build design/design.md and download UI assets.

/spec-plan

Build claude/plan.md with 8-10 step deliverables.

/spec-feature

Run the full feature development cycle.

/spec-refactor

Clean only the current cycle’s diff - nothing else.

/spec-bug

Isolated bug resolution: reproduce, test, smallest fix.

/spec-docs

Reconcile docs against reality - never touches source.

/spec-sync

Reconcile context.md against actual repo state.

Guarantees, not vibes.

Measurable commitments the Kit holds itself to.

≤ 8k

tokens to load full project context on a mature repo

≤ 120%

cost of a 5th feature cycle vs. the first

ordered steps, none skipped without a logged override

channels - npm + PyPI - from one source of truth

Read the docs. Run the cycle.

Get started ›Why Throughspec