# Which SKU do I need? (/docs/which-sku) The `@pleach/*` surface is 14 published packages (plus `@pleach/observe` in alpha and the reserved `@pleach/trust-pack`). Most projects need **three or four**. The packages are branches grafted onto one lattice — pick the branches that carry weight for what you're building, leave the rest for later. This page maps what you're building to the shortest install list, plus a one-line reason for each. If you're not sure, start with the first row — `@pleach/core` alone covers more cases than you'd guess. ## The shortest answer [#the-shortest-answer] | You want | Install | Read | | --------------------------------------------------- | ----------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------- | | **A streaming chat handler in 5 lines** | `@pleach/core` | [Getting started](/docs/getting-started) | | **A chatbot with a working UI** | `@pleach/core`, `@pleach/react` | [`recipes/simple-chatbot`](/docs/recipes/simple-chatbot) | | **RAG over your knowledge base** | `@pleach/core`, `@pleach/react` (+ your vector store) | [`recipes/rag-chatbot`](/docs/recipes/rag-chatbot) | | **An agent with tools** | `@pleach/core`, `@pleach/base-tools`, `@pleach/tools` | [Tools](/docs/tools), [`@pleach/base-tools`](/docs/base-tools) | | **A coding agent (SWE-bench-shaped)** | `@pleach/core`, `@pleach/coding-agent`, `@pleach/sandbox` | [`@pleach/coding-agent`](/docs/coding-agent) | | **A multi-tenant SaaS with per-tenant cost rollup** | `@pleach/core`, `@pleach/gateway` | [Multi-tenant](/docs/multi-tenant), [Gateway](/docs/gateway) | | **OTel-instrumented observability** | `@pleach/core` (OTel is built in); `@pleach/observe` (alpha) adds destination plugs | [`@pleach/observe`](/docs/observe) | | **PII / PHI scrubbing for HIPAA / GDPR / PCI-DSS** | `@pleach/core`, `@pleach/compliance`, `@pleach/compliance-contract` | [Compliance](/docs/compliance), [Scrubbers](/docs/scrubbers) | | **Regression-grade evals against the audit log** | `@pleach/core`, `@pleach/eval`, `@pleach/replay` | [`@pleach/eval`](/docs/eval), [`@pleach/replay`](/docs/replay) | | **An MCP server backed by Pleach sessions** | `@pleach/core`, `@pleach/mcp` | [`@pleach/mcp`](/docs/mcp) | | **A LangChain / LangGraph adapter layer** | `@pleach/core`, `@pleach/langchain` | [`@pleach/langchain`](/docs/langchain), [Migrating from LangChain](/docs/migrating-from-langchain) | The recipes column on the right is the canonical worked example for each row. Most of them are under 100 lines of glue over `@pleach/core`. ## Shortcuts by shape [#shortcuts-by-shape] If "what are you building?" is too narrow a question, here are seven common shapes the runtime is built around. Each maps to a recipe in `@pleach/recipes` and a SKU bundle. ### SaaS adding a chat tab [#saas-adding-a-chat-tab] A typical multi-tenant web app that wants a chatbot tab. You own your auth, your DB, your billing. Add Pleach without touching any of them. **Install:** `@pleach/core`, `@pleach/react` **Recipe:** [`simpleChatbot`](/docs/recipes/simple-chatbot) **Reach for next:** `@pleach/observe` (alpha) once you want per-tenant cost rollup. ### Vertical agent (specific tools, specific knowledge) [#vertical-agent-specific-tools-specific-knowledge] You're shipping an agent for a specific domain — legal review, medical coding, ops triage — with a curated tool set and a knowledge base. Not generic ChatGPT-shaped. **Install:** `@pleach/core`, `@pleach/base-tools`, `@pleach/tools` **Recipe:** [`verticalAgent`](/docs/recipes/vertical-agent) ### Compliance-bound (regulated industry) [#compliance-bound-regulated-industry] HIPAA, GDPR, PCI-DSS, SOC 2. You need scrubbers on inbound content, audit attestation on every call, and a hash chain you can prove to a regulator. **Install:** `@pleach/core`, `@pleach/compliance`, `@pleach/compliance-contract` **Recipe:** [`compliantChatbot`](/docs/recipes/compliant-chatbot) **Reach for next:** `@pleach/replay` once you need chain-verifier attestation. ### On an existing Anthropic / OpenAI Enterprise contract [#on-an-existing-anthropic--openai-enterprise-contract] You already have an Anthropic Enterprise or OpenAI Enterprise contract — SSO, ZDR, Workspaces / Projects. You want per-axis cost rollup *inside* one Workspace without a new vendor. **Install:** `@pleach/core`, `@pleach/gateway` (+ `@pleach/observe`, alpha) **Recipe:** [`enterpriseAgent`](/docs/recipes/enterprise-agent) **Read first:** [Migrating from Anthropic Enterprise](/docs/migrating-from-anthropic-enterprise) or [Migrating from OpenAI Enterprise](/docs/migrating-from-openai-enterprise). ### Multi-tenant platform (per-customer BYOK + billing) [#multi-tenant-platform-per-customer-byok--billing] You're running multiple customer agents on the same substrate, with per-customer BYOK, per-customer policies, and per-customer billing. **Install:** `@pleach/core`, `@pleach/gateway`, `@pleach/compliance` **Recipe:** [`enterpriseAgent`](/docs/recipes/enterprise-agent) * [Multi-tenant SaaS agent](/docs/multi-tenant-saas-agent). ### Subagent swarm (bounded fan-out under a root turn) [#subagent-swarm-bounded-fan-out-under-a-root-turn] A root agent that spawns N specialist sub-agents and reconciles their answers, with a per-root-turn cost ceiling. Common shape for research, planning, and refactor agents. **Install:** `@pleach/core`, `@pleach/recipes` **Recipe:** [`subagentSwarm`](/docs/recipes/subagent-swarm) ### Regression-grade eval lab [#regression-grade-eval-lab] You want fixture-driven eval against the audit log with replay determinism and Welch t-test scoring. CI-runnable, not notebook-shaped. **Install:** `@pleach/core`, `@pleach/eval`, `@pleach/replay` **Recipe:** [`evalLab`](/docs/recipes/eval-lab) ## When you don't need a sibling SKU [#when-you-dont-need-a-sibling-sku] `@pleach/core` already ships these in the substrate; you don't need a sibling for them: * **Session lifecycle, channels, checkpointing.** Built-in. * **Storage adapters** (Memory / IndexedDB / Supabase). Built-in. * **Family-lock, model resolution matrix, transport selection.** Built-in. * **`AuditableCall` row + event log + hash chain (schema-side).** Built-in. The verifier ships in `@pleach/replay`. * **OpenTelemetry spans (session.turn, llm.invocation, etc.).** Built-in. `@pleach/observe` (alpha, not yet on npm) adds destination plugs (Postgres, Supabase, Pleach Hosted); core ships the OTel emission. * **Plugin contract.** Built-in. Authoring conventions in [Plugin authoring standards](/docs/plugin-authoring-standards). * **The four-stage lattice + singleton synthesize seam.** Built-in invariants enforced by lint on the core repo. ## Quick "do I install this?" gut-checks [#quick-do-i-install-this-gut-checks] A few SKUs get asked about more than others. Short answers: * **`@pleach/base-tools`** — install if you want a working agent today and you don't have a domain tool set yet. Ships math, datetime, scratchpad, unit\_convert, text\_search, opt-in url\_fetch. * **`@pleach/tools`** — install if you're authoring tool definitions. Provides the contract + Zod helpers + queryable registry. Skip if you're using `@pleach/base-tools` directly. * **`@pleach/sandbox`** — install if you're running untrusted code (coding agent, user-supplied scripts). Contract today; vendor adapters land under `@pleach/sandbox-`. * **`@pleach/recipes`** — install if you want high-level factories (`simpleChatbot`, `ragChatbot`, `compliantChatbot`, `verticalAgent`, `subagentSwarm`, `enterpriseAgent`) instead of wiring `SessionRuntime` from scratch. * **`@pleach/trust-pack`** — reserved name. Not shipping code today. Don't install. ## Where to go next [#where-to-go-next]