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 breaks a contract, freestyle agents pin apiVersion, invent maps, or open store-only “done” PRs. Layerkit makes the agent read docs/OpenAPI/code, edit real client source (not generate 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
        ↓
  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.

Outcome	Freestyle agent	With Layerkit
Pin-only / SDK bump as “full integrate”	Common	Blocked — field edits or residual required
Multi-lang package (node/python/ruby/…)	Often one language	Surfaces inventory; PR blocked until all updated\|residual
Handoff	Memory/store or fake PR URL	Live `pr:` URL (verified) or residual break-glass
Evidence	Optional	Fail-closed mark-done (docs URLs, paths on disk)

Quick start

npm install -g layerkit   # or: npx layerkit --help

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

# Intentional integrate / contract heal (agent must opt in)
layerkit help
layerkit agent start --mode heal --vendor <vendor>
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 "heal multilang"

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

What you get

Area	Purpose
Skills	How the agent researches, maps, edits production source, reviews privacy, and hands off
Pipeline	`discover → surfaces → research → design → author → privacy → deletion-first → source-edit → handoff`
CLI rails	Fail-closed `agent next` / `mark-done`, surface inventory, package verify, PR open/reuse
Evals	CI gates + skill-train that block freestyle holes (pin-only, invent fields, store-only PR)
Project store	Local evidence, maps, proposals, memory under `.layerkit` (session workspace — not the product)

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.

Agent workflow

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 in the package → 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 agent start --mode full|heal --vendor <v>
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 "heal multilang"] [--no-reuse]

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

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:

Priority	Source
1	CLI `--project-dir <path>`
2	Env `LAYERKIT_PROJECT_DIR`
3	Repo pointer `layerkit.path.json` / `layerkit.json`
4	Default `{repo}/.layerkit`

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 state and handoff helpers
libs/domain/              Shared schema/types for proposals and maps
evals/                    CI gates and skill judges
skills/                   Agent skills shipped in the package
docs/                     Agent/operator docs

Validate

npm run build
npm run eval:ci
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.