mcp· @zero/mcp-server · 7 resources · 9 tools · 0 SDK deps

the brand is queryable by every coding agent

MCP — the Model Context Protocol — is the canonical way an external coding agent (cursor · claude desktop · claude code · github copilot · windsurf) talks to a local data source. @zero/mcp-server ships as a stdio CLI · zero transitive dependencies · 7 canonical resources (primitives, DESIGN.md, AGENTS.md, DTCG, receipts, token graph) and 9 tools. add it to ~/.cursor/mcp.json and every agent in the room speaks the brand.

initialize · responseid 1

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "protocolVersion": "2024-11-05",
    "capabilities": {
      "resources": {
        "listChanged": false,
        "subscribe": false
      },
      "tools": {
        "listChanged": false
      }
    },
    "serverInfo": {
      "name": "@zero/mcp-server",
      "version": "1.0.0"
    }
  }
}

as of2026-05-14 · 19:05z

00 · livepick a tool · fill args · call · same handle() Cursor and Claude Desktop hit over stdio

the protocol calls itself

mcp · live· /api/mcp · in-process · same handle() over stdio · 0 calls · last 0msconnected0 tools

tool · pick · args · call—

— · loading tools/list…

— · no arguments required

as of2026-05-14 · 19:05z

01 · protocolJSON-RPC 2.0 over stdio · 6 methods

the wire shape every coding agent already speaks

plate · A · JSON-RPC method surface6 methods

metric: mcp
unit: requests
window: static · fixture
agg: count
source: packages/mcp-server/src/protocol.ts
fresh: last build

method	params	result	used by
`initialize`	protocolVersion, clientInfo	capabilities, serverInfo	handshake · always first
`notifications/initialized`	—	{}	post-handshake ack
`resources/list`	—	{ resources: [] }	discover what is readable
`resources/read`	{ uri }	{ contents: [...] }	fetch one resource
`tools/list`	—	{ tools: [] }	discover invocable tools
`tools/call`	{ name, arguments }	{ content: [...] }	invoke a tool

as of2026-05-14 · 19:05z

02 · resources7 canonical zero://… URIs

every brand answer is a resource

plate · B · resources/list · live response7 resources

metric: mcp
unit: requests
window: static · fixture
agg: count
source: packages/mcp-server/src/protocol.ts · RESOURCES
fresh: last build

uri	name	mime	description
`zero://primitives`	primitives	`application/json`	The complete @zero/ui primitive catalog with .meta dossiers (states, tokens, description, surfaces).
`zero://design.md`	DESIGN.md	`text/markdown`	The canonical design system context layer (YAML frontmatter + Markdown rationale). v2026-05-10+.
`zero://agents.md`	AGENTS.md	`text/markdown`	The canonical agent instructions (the 60K-repos standard). Read once at session start.
`zero://tokens/dtcg`	tokens (W3C DTCG v1.0)	`application/json`	The 17-category token graph emitted in W3C Design Tokens Community Group format. OKLCH-native.
`zero://receipts/vocabulary`	receipt vocabulary	`application/json`	The eight-receipt vocabulary (trade, refuse, sign, settlement, demolition, revoke, rotate, migrate). ADR-027.
`zero://tokens/graph`	tokens graph (ADR-035)	`application/json`	Explicit dependency graph of every token (nodes + edges + per-category counts). Built from tokens.json + skin contracts.
`zero://cockpit/sitemap`	cockpit sitemap (ADR-048)	`application/json`	The walkable surface of the cockpit · every verb (what an operator does) and every chapter (where they land). Mirrors the body served at /api/sitemap.json over HTTP.

as of2026-05-14 · 19:05z

03 · tools9 invocable tools · all pure, all replayable

every brand check is a tool

plate · C · tools/list · live response9 tools

metric: mcp
unit: requests
window: static · fixture
agg: count
source: packages/mcp-server/src/protocol.ts · TOOLS
fresh: last build

name	required	description
`lookup_primitive`	`name`	Return the .meta dossier for a single primitive by name (e.g. "Button", "Receipt", "AlertDialog").
`validate_token_usage`	`variable`	Given a CSS variable name (e.g. "--amber"), return the token category, value, and rules-of-use.
`list_chapters`	`—`	Return the brand-book chapter index from living-system.contract.json.
`cockpit_lookup_verb`	`query`	Look up a single cockpit verb by id or by case-insensitive label substring (e.g. "spawn", "verb-graph"). Returns the entry with its href so the agent can navigate the operator straight to the live demo.
`cockpit_navigate`	`verb`	Return a navigation receipt describing what the operator would land on if the agent navigated them to a verb. Includes the canonical URL on getzero.dev, the owning chapter, the hash anchor target id, and the heading text the operator will see at landing. The agent does not actually trigger the navigation — it gets a server-side preview so it can describe the destination before the click.
`execute_action`	`actionId`	ADR-058 · MX write-side · return an execution receipt describing what the cockpit would do if the agent dispatched the named action via window.__shell.executeAction(). The MCP server itself never executes (constitutional safe-scope · cockpit-internal only); the receipt enumerates the action id, expected type (navigate\|execute\|create\|configure), reversibility, the route the operator is on, and the canonical URL the action lives on. The headless caller posts the receipt back to the in-cockpit __shell to actually fire.
`submit_form`	`chapter`	ADR-058 · MX write-side · return a submission receipt for a form on a known cockpit chapter. Lists the form's field ids (data-field) and their declared types as MX-readable rows. The receipt is a discovery surface; actual submission still requires the operator to interact in the cockpit.
`read_state`	`chapter`	ADR-058 · MX read-side · return the current MX-readable state for a given chapter: every data-component on the page, every data-action element with its action type and reversibility, every data-metric value with its unit. The agent uses this to know what the operator is looking at without scraping HTML.
`quote`	`—`	ADR-084 · runtime · return a deterministic paper-only market quote (bid/ask/mid/spread/depth) from @zero/runtime. The quote is labelled venue=paper and is NOT tradable from this surface. Article II.1: paper-only. Two callers passing the same (market, ts) get the same quote forever. Use `markets` argument to enumerate the seeded markets without quoting one.

as of2026-05-14 · 19:05z

04 · trace4 build-time fixture requests · reduced through the real handler

the protocol is queryable from the brand book

plate · D · tools/call · lookup_primitive('ApprovalGate')id 4

metric: mcp
unit: requests
window: static · fixture
agg: count
source: handle(REQUESTS[3])
fresh: last build

name: —
num: —
states: —
tokens: 0 tokens
description: —

plate · E · full request / response trace4 pairs

metric: mcp
unit: requests
window: static · fixture
agg: count
source: REQUESTS · RESPONSES
fresh: last build

id	method	shape of result
1	`initialize`	`protocolVersion · capabilities · serverInfo`
2	`resources/list`	`resources`
3	`tools/list`	`tools`
4	`tools/call`	`content · isError`

as of2026-05-14 · 19:05z

05 · wiringcursor · claude desktop · windsurf · github copilot

point your agent at the server in three lines

plate · F · example · ~/.cursor/mcp.jsoncopy/paste

metric: mcp
unit: requests
window: static · fixture
agg: count
source: cursor docs · mcp.json
fresh: last build

{
  "mcpServers": {
    "zero-brand": {
      "command": "node",
      "args": ["packages/mcp-server/dist/cli.js"]
    }
  }
}

zero transitive deps · zero network

the server reads files in the repo (manifest, DESIGN.md, AGENTS.md, DTCG, the receipt vocabulary, the token graph) and answers JSON-RPC requests on stdio. nothing leaves the machine. the agent gets the brand answer with one resources/read instead of greping the repo.

stdiozero depscontract-pinned◆ mcp001a