Layerkit

Evidence-first AI agents that integrate and heal vendor APIs like a senior developer — production code, multi-lang surfaces, live PRs.

When a vendor renames fields or a package needs a new vendor, freestyle agents pin apiVersion, invent maps, open store-only “done” PRs, or invent a parallel facade beside existing adapters. Layerkit makes the agent read docs/OpenAPI/code, follow the client’s existing multi-vendor path (registry + sibling adapters), edit real production source (not a sidecar SDK), cover every language surface, and ship a real GitHub PR — or an honest residual when there is nothing to change.

docs / OpenAPI / curl / code
        ↓
  discover siblings → research → map → production source edits (all languages)
        ↓
  package verify → live PR  (or residual-no-pr break-glass)

Layerkit is not a runtime integration SDK and not a config-only installer. Skills + deterministic CLI rails force process; the client package remains the source of truth.

Quick start

npm install -g layerkit   # or: npx layerkit --help
# current release: see npm badge above (0.1.4+)

cd /path/to/your/client/package
layerkit install --platform claude   # or codex | cursor | copilot | …
layerkit doctor

# Intentional integrate / contract heal (user must opt in)
layerkit help
layerkit agent start --mode full --vendor <vendor>    # first integrate (default)
# layerkit agent start --mode heal --vendor <vendor>  # contract update when domain known
layerkit agent next          # skill packet — follow THAT skill only
# … evidence-backed research & production edits …
layerkit agent mark-done --step <id> --evidence <note.md>
layerkit pr open --title "…" --body "…" --pr-match "integrate <vendor>"
layerkit handoff write --vendor <vendor> --goal "…" --quality "package_verify: green"

User opt-in examples: layerkit: full integrate acme, /layerkit heal stripe, @layerkit contract update.

Platforms: codex · claude · cursor · copilot · opencode · openhands · devin · windsurf · factory-droid · antigravity

What you get

Semantic mapping, renames, and source edits are agent work (docs + code). The CLI validates structure, order, evidence, surfaces, and live PR existence — it does not invent vendor fields or replace your production datalayer.

Modes: full vs heal

Full integrate on multi-vendor packages: inventory sibling adapters/registries/tests → research the new vendor from docs → design by following the existing path (same module root + registry wire) → production adapter + clone sibling tests → package verify → live PR. Parallel facades and pin-only bumps are fail-closed.

Master skill: layerkit-orchestrate-integration.

discover → surfaces → research → design → author → privacy → deletion-first → source-edit → handoff

Contract heal: human/docs/OpenAPI → agent cites evidence → edits existing mappers/adapters/tests → layerkit pr open (or residual). Prefer updating existing code; deletion-first before additive work.

Deletion-first is mandatory:

• Before adding code, identify existing code/docs/tests that can be removed or rewritten.
• Prefer modifying or deleting existing code over adding files.
• Do not add an abstraction until the existing abstraction is proven insufficient.
• For every new file/function/export, list what it replaces. If it replaces nothing, justify why it must exist.
• Target net-negative or near-neutral LOC unless functionality truly expands.

Commands

layerkit install --platform codex|claude|cursor|copilot|opencode|openhands|devin|windsurf|factory-droid|antigravity \
  [--hooks enabled|disabled] [--map-reminders enabled|disabled] [--poc] [--user-config]
layerkit doctor
layerkit repo status
layerkit help
layerkit cheatsheet

layerkit agent start --mode full|heal --vendor <v> [--force-reset]
layerkit agent status
layerkit agent next
layerkit agent mark-done --step discover|surfaces|research|design|author|privacy|deletion-first|source-edit|handoff --evidence <path>

layerkit pr open --title "…" --body "…" [--pr-match "…"] [--no-reuse]
layerkit handoff write --vendor <v> --goal "…" [--done …] [--next …] [--blocked …] [--quality "package_verify: green"]

layerkit map list
layerkit map show <vendor>
layerkit map validate <file>

layerkit proposal write map --vendor <v> --out ./map.json --source title=url … --field domain:vendor …
layerkit proposal validate <file>   # read-only structural check
layerkit proposal submit <file>
layerkit proposal approve <id>
layerkit proposal apply <file-or-id>

layerkit memory list
layerkit memory search "<query>"
layerkit memory show <id>
layerkit memory append --type research --title "<title>" --body-file <file>

Project Store

Layerkit stores agent working state under a project directory, defaulting to .layerkit.

Resolution order:

Production paths listed in source-edit evidence are resolved against the customer package root (git/repo root), not the .layerkit store — so src/vendors/… paths must exist on disk under the package.

Client projects usually should not commit .layerkit/maps unless the team intentionally wants reviewed map artifacts in source control. Production source edits and tests belong in the client package itself.

Package Layout

apps/cli/                 CLI entry
libs/install/             Platform install support
libs/vendor-memory/       Local maps, proposals, sessions, memory
libs/proposal/            Proposal scaffold and validation
libs/hallucination/       Evidence and hallucination guardrails
libs/agent/               Pipeline, skill packets, surfaces, PR open, handoff
libs/domain/              Shared schema/types for proposals and maps
evals/                    CI gates, skill-train curriculum, fixtures
skills/                   Agent skills shipped in the package
docs/                     Agent/operator docs

Validate / develop

npm run build
npm run eval:ci          # merge bar
npm run eval:skill-train # skill-text + agent-run judges
npm run pack:check

See docs/CHEATSHEET.md and docs/AGENT_GOLDEN_PATH.md for the operator flow. See MATURITY.md, SECURITY.md, and docs/API_STABILITY.md for release expectations. Contributing: CONTRIBUTING.md.

Release notes (0.1.4)

• Multi-vendor full integrate training: skills + skill-train scenarios for “follow sibling path / no parallel facade”
• Source-edit mark-done resolves production paths against package root (fixes false source_edit_paths_not_on_disk when files live under src/)
• README aligned with intentional entry, full vs heal, surfaces, PR/handoff rails