graft

---
name: graft
description: >-
license: Apache-2.0
---

# Graft

Use this skill when the task is about creating or refining a Graft server, wrapping an existing API with Graft proxy mode, or updating contributor-facing docs and examples so they match the current `graft` package behavior.

## Product thesis

Graft's core value has three parts:

1. **Define once** — tools with a name, schema, and handler.
2. **Serve as HTTP and MCP** — from the same server, through a single shared pipeline (same auth, validation, middleware).
3. **Discovery is automatic** — agents find tools via `agent.json`, `mcp.json`, `llms.txt`. Humans get interactive docs (`/docs`) and an OpenAPI spec (`/openapi.json`). Zero configuration.

When explaining Graft, lead with all three parts. When showing examples, demonstrate both access patterns (MCP and HTTP) and mention what the server auto-serves. This applies to both source-based apps and proxy mode.

## Workflow

1. Identify the mode before proposing changes:
- App authoring: `createApp(...)`, tools, resources, prompts, HTTP routes, Node or fetch integration.
- Proxy/OpenAPI: `graft serve --openapi ...` or `graft.proxy.yaml`.
- Docs/release hygiene: README, install instructions, skills, examples, contributor checks.

2. Ground in the current repo before using memory:
- If tool access is available, inspect the current source, public exports, CLI commands, scaffold templates, and tests.
- If tool access is not available, ask for the smallest set of files or examples needed to avoid guessing.

3. Follow the current public contract in examples and reviews:
- Inline tool examples: prefer `app.tool('name', config)`.
- Modular tool examples: prefer `defineTool(...)` plus `app.tool(definedTool)`.
- Auth shapes: `true`, `['role']`, or `{ roles: [...] }`.
- MCP Streamable HTTP endpoint: `POST /mcp`.
- Auto-served framework endpoints: `/.well-known/agent.json`, `/.well-known/mcp.json`, `/openapi.json`, `/docs`, `/llms.txt`, `/llms-full.txt`, `/health`.
- Full CLI: `serve`, `dev`, `check`, `test`, `studio`, `install`, `add-tool`.
- When showing tool examples, demonstrate both the MCP `tools/call` invocation and the equivalent HTTP request (e.g. `GET /list-items?q=hello` or `POST /create-entry`).

4. Use tools where they materially improve correctness, but stay portable:
- With repo or shell access, inspect files and run validation commands after making changes.
- Without repo or shell access, state assumptions explicitly and keep recommendations tied to visible source or user-provided snippets.

5. Load only the reference you need:
- App authoring: [references/app-authoring.md](references/app-authoring.md)
- Proxy/OpenAPI wrapping: [references/proxy-openapi.md](references/proxy-openapi.md)
- Validation, docs, and release hygiene: [references/validation-release.md](references/validation-release.md)

## Quick examples

### Inline tool — both access patterns

```ts
import { createApp } from '@schrepa/graft'
import { z } from 'zod'

const app = createApp()

app.tool('list_items', {
  description: 'List items matching a query.',
  params: z.object({ q: z.string() }),
  auth: true,
  handler: async ({ q }) => ({
    items: ['hello', 'world'].filter((item) => item.includes(q)),
  }),
})

export default app
```

**MCP (`tools/call`):**
```json
{ "method": "tools/call", "params": { "name": "list_items", "arguments": { "q": "hello" } } }
```

**HTTP equivalent:**
```
GET /list-items?q=hello
Authorization: Bearer <token>
```

The same handler, auth middleware, and validation run for both.

### Proxy mode — `graft.proxy.yaml`

```yaml
target: https://petstore3.swagger.io/api/v3
tools:
  - method: GET
    path: /pet/findByStatus
    name: find_pets_by_status
    description: Find pets by status.
    parameters:
      type: object
      properties:
        status:
          type: string
  - method: POST
    path: /pet
    name: create_pet
    description: Create a pet.
    parameters:
      type: object
      properties:
        name:
          type: string
      required: [name]
```

Start the proxy server:
```
graft serve --config graft.proxy.yaml
```

Graft exposes each configured operation as both an HTTP endpoint and an MCP tool, and auto-generates `/openapi.json`, `/docs`, and discovery files.

For the direct OpenAPI path, use:
```
graft serve --openapi ./openapi.yaml --target https://api.example.com
```

## Guardrails

- Do not document unsupported behavior just because an older example mentioned it.
- Keep examples executable and small; prefer one correct pattern over many variants.
- Prefer current source and tests over stale notes, blog posts, or memory.
- Do not mention registry or publishing artifacts unless they actually exist in the repo being edited.
- When a docs claim is likely to drift, add or update an automated check.