@particle-academy/agent-integrations

MCP-driven agent presence in collab sessions. Each open session gets a micro-MCP server running in-page; agents (in-browser or external via relay) connect to it and act as participants — adding sticky notes, drawing, moving items, leaving cursor trails.

Also ships the agent UX surface: a chat-and-tool-log panel, an on-canvas presence cursor, and a brief activity highlight for items the agent just touched.

v0.1 — focused on @particle-academy/fancy-whiteboard as the first bridged surface. The bridge layer is package-agnostic, so other fancy-* packages can register their own tool sets per session.

Install

npm install @particle-academy/agent-integrations

import "@particle-academy/agent-integrations/styles.css";

Which version range to depend on

Use a caret. ^0.46.0 is correct here, and it is deliberate.

"@particle-academy/agent-integrations": "^0.46.0"

This package is pre-1.0, and breaking changes land in MINOR releases — see the note at the top of CHANGELOG.md. A caret on a 0.x locks the minor (npm reads ^0.46.0 as >=0.46.0 <0.47.0), so it gives you patches and holds you at a surface you have already integrated against. That is the right default when the next minor may change something under you.

Moving up a minor is a deliberate act. Read that version's CHANGELOG.md entry before you do — breaking entries say what a consumer must actually DO, and about half of what reads as breaking needs no action at all.

A note on the rest of the suite. Some Fancy packages recommend an open >=X <2.0 range instead. That is not an inconsistency: those packages carry a runtime compatibility check that fails loudly when a consumer is out of step — fancy-connector-core's CONNECTOR_API_VERSION is the example — which is a stronger guarantee than a caret and makes the caret unnecessary. This package has no such check, so the caret is doing real work.

The rule inside the suite differs again: first-party packages depend on each other with an open range because they are released and tested together at a kit version. A consumer is not, which is why the advice here is not the same.

Tree-shake-safe imports

The root barrel is core-only — MCP server, presence, undo, sharing, plus the bridges and components that don't depend on optional peer packages (fancy-sheets, fancy-forms, fancy-code, fancy-charts, fancy-scene, fancy-screens).

Bridges whose peer is optional (fancy-whiteboard, fancy-flow) and the SharedWhiteboard component are reachable only via subpath imports so a consumer that hasn't installed those peers bundles cleanly:

// Core — always safe:
import {
  MicroMcpServer,
  attachInProcess,
  registerSheetsBridge,
  useSheetsAdapter,
  useSheetsActivityHighlights,
} from "@particle-academy/agent-integrations";

// Optional peers — subpath imports:
import { registerWhiteboardBridge } from "@particle-academy/agent-integrations/bridges/whiteboard";
import { registerFlowBridge }       from "@particle-academy/agent-integrations/bridges/flow";
import { SharedWhiteboard }         from "@particle-academy/agent-integrations/components/shared-whiteboard";

Every bridge has a matching subpath if you'd rather import surgically:

| Bridge | Subpath | | ------------------- | ------------------------------------------------------ | | whiteboard | …/bridges/whiteboard | | flow | …/bridges/flow | | sheets | …/bridges/sheets | | forms | …/bridges/forms | | code | …/bridges/code | | charts | …/bridges/charts | | scene | …/bridges/scene | | screens | …/bridges/screens | | screen contents | …/bridges/screen-doc | | passkeys | …/bridges/passkeys | | sheets adapter hook | …/sheets-adapter | | presence | …/presence | | undo | …/undo | | sharing | …/sharing |

registerScreensBridge handles navigation between screens.

Screens bridge: acknowledge after the host commits

Every mutating screens adapter method (setActive, createScreen, destroyScreen, updateScreenContent) may return void or a Promise. A sync void adapter behaves exactly as it always has. When the host's commit is asynchronous and authoritative (persisted state, a possible refusal or conflict), return a Promise and the bridge waits for it:

• the tool reports success, and emits its AgentActivity event, only after the promise resolves;
• a rejection, or a resolved { ok: false, error }, becomes an error result carrying the host's error text (its message only, never a stack), and emits no activity;
• screens_create calls createScreen and then setActive. If createScreen fails, setActive is never called. If setActive fails after a successful create, the result is an error saying the screen was created but not activated (with structuredContent: { id, kind, created: true, activated: false }), and one activity event is still emitted because the create did commit.

import {
  registerScreensBridge,
  type ScreensAdapterResult,
} from "@particle-academy/agent-integrations/bridges/screens";

registerScreensBridge(host, {
  adapter: {
    listScreens: () => store.screens,
    getActive: () => store.activeId,
    // Resolve once the server has persisted it; refuse with a reason the agent can act on.
    setActive: async (id): Promise<ScreensAdapterResult> => {
      const res = await api.post(`/screens/${id}/activate`);
      return res.ok ? { ok: true } : { ok: false, error: res.reason, code: "conflict" };
    },
    createScreen: async (spec) => {
      await api.post("/screens", spec); // a throw becomes an error result
    },
  },
});

The screens bridge pushes no undo entries: agent_undo cannot revert a screens tool. Keep your own history if you need to.

Form bridge: acknowledge after the host accepts the write

setValue and setValues on FormBridgeAdapter may return void or a Promise (FormAdapterCommit). A sync void setter behaves exactly as it always has. When the host's write is authoritative (a persisted draft, a server that can refuse it or report it stale), return a Promise and the bridge waits for it:

• form_set_value / form_set_values report success, and emit their AgentActivity event, only after the promise resolves to void or { ok: true }. Your getValue / getValues should return the new value by then, so a read straight after a success sees it.
• A rejection, or a resolved { ok: false, error } (FormAdapterResult), is that call's error result, carrying the host's error text (its message only, never a stack), and emits no activity. Leave your state unchanged when you refuse.
• Without setValues, form_set_values awaits setValue once per field, in order, and stops at the first refusal. Earlier fields stay committed (that path is not atomic): the error names them, structuredContent carries { committed, failed, notAttempted }, and one activity event is emitted for the committed part. Provide setValues if the batch must be all-or-nothing.
• If you dispose() the bridge (the form closes) while a write, a confirm or a submit is pending, the call settles at once as an error saying the outcome is unknown, emits no activity, and a later settle is ignored. A submit whose human confirm was still pending is never sent.

import {
  registerFormBridge,
  type FormAdapterResult,
} from "@particle-academy/agent-integrations/bridges/forms";

registerFormBridge(host, {
  adapter: {
    id: "invoice-draft",
    getFields: () => fields,
    getValue: (name) => draft.values[name],
    getValues: () => ({ ...draft.values }),
    // Resolve once the server has accepted it; refuse with a reason the agent can act on.
    setValue: async (name, value): Promise<FormAdapterResult> => {
      const res = await api.patch(`/drafts/${draft.id}`, { [name]: value, version: draft.version });
      if (!res.ok) return { ok: false, error: res.reason, code: res.status === 409 ? "stale" : undefined };
      draft = res.draft; // update state BEFORE resolving
      return { ok: true };
    },
  },
});

Staleness is the host's call. The bridge has no expected-value / version argument: your write is the authority, so check your own version or ETag there and refuse with { ok: false, error: "Draft changed since you read it; re-read and retry", code: "stale" }. The agent gets that sentence as the tool error.

The form bridge pushes no undo entries.

Several forms on one host

Since 0.53.0, call registerFormBridge once per form on the same host. The first form registers the form tools; later forms join them, so the tool list stays the same eight tools however many forms are mounted:

import { registerFormBridge } from "@particle-academy/agent-integrations/bridges/forms";

const billing = registerFormBridge(host, { adapter: billingAdapter });   // adapter.id === "billing"
const shipping = registerFormBridge(host, {
  adapter: shippingAdapter,                                              // adapter.id === "shipping"
  pendingMode: false,                     // per form: shipping submits without a human confirm
  agent: { id: "checkout-agent", name: "Checkout" },
});

// An agent then picks the form with the `form` argument:
await host.callTool("form_list", {});                     // [{ id: "billing", … }, { id: "shipping", … }]
await host.callTool("form_set_value", { form: "shipping", field: "street", value: "2 Ship Rd" });
await host.callTool("form_set_value", { field: "street", value: "?" });
// → error: 2 forms are mounted, so pass "form" with one of: "billing", "shipping". form_list describes them.

shipping.dispose(); // removes only shipping; billing keeps working, and `form` is optional again
billing.dispose();  // the last form: every form tool is withdrawn

• form is accepted by every form tool. With exactly one form mounted it is optional, so a single-form host and its agent prompts work exactly as before. With two or more, a call without it is refused with the mounted ids listed. An id that is not mounted is always refused, never routed to another form.
• form_list returns { forms: [{ id, title, screenId, fields }] }.
• Each form is identified by adapter.id, which must be a non-empty string. Registering an id that is already mounted replaces it (a remount); the earlier registration's dispose() then leaves the newer one in place.
• pendingMode, adapter.confirm, agent and the presence target stay per form; activity names <formId>:<field> on the form's own screenId.
• dispose() settles only that form's pending writes, with the "outcome unknown" error described above.
• The tools are held by one registrant ("form-bridge"), so an unrelated registrant claiming a form tool name is still refused.

<BridgedForm> needs no change: several of them may now share one server. Background and the alternatives considered: docs/multi-form-hosts.md.

Flow bridge: awaited, atomic graph commits

Since 0.54.0, FlowBridgeAdapter takes an optional commit(op). Without it, nothing changes: the flow tools call setNodes / setEdges and report success straight away, as before. Wire it when your graph write is authoritative (a persisted graph, a server that can refuse a write or report it stale):

• Every mutating tool (flow_add_node, flow_update_node, flow_delete_node, flow_connect, flow_disconnect, and flow_set_node_status when no setNodeStatus is wired) builds one FlowGraphOp and awaits commit instead of calling the setters. It reports success, and emits its AgentActivity event, only once commit returns or resolves to void or { ok: true }.
• A rejection, a throw, or { ok: false, error, code? } (FlowAdapterResult) is that call's error: the text is your error (message only, never a stack), structuredContent is { ok: false, op, error, code? }, and no activity is emitted.
• remove_node carries the node and the ids of every edge it removes. Apply it as one write; the bridge never splits it.
• Each op carries revision (from your optional getRevision(), read when the op was computed), the acting agent and the tool. The op is not recomputed after the await, so check revision and refuse with code: "stale" if your graph has moved.
• Validation (validateConfig, validateConnections, unknown ids) and the pendingMode confirm run before commit. A refused or declined call never reaches it.
• If the bridge is disposed, or another flow bridge is registered on the same host, while a commit or a delete confirm is pending, the call settles at once as an error saying the outcome is unknown, and a later result is ignored.

import {
  registerFlowBridge,
  type FlowGraphOp,
  type FlowAdapterResult,
} from "@particle-academy/agent-integrations/bridges/flow";

registerFlowBridge(host, {
  adapter: {
    getNodes: () => graph.nodes,
    getEdges: () => graph.edges,
    setNodes, // still required by the type; unused once commit is wired
    setEdges,
    getRevision: () => graph.version,
    commit: async (op: FlowGraphOp): Promise<FlowAdapterResult> => {
      const res = await api.post(`/flows/${flowId}/ops`, { op, baseVersion: op.revision });
      if (!res.ok) return { ok: false, error: res.reason, code: res.status === 409 ? "stale" : undefined };
      graph = res.graph; // update state BEFORE resolving
      return { ok: true };
    },
  },
});

Runs and cancels (since 0.55.0) follow the same contract. flow_run and flow_cancel await adapter.run / adapter.cancel:

• cancel may return void, FlowAdapterResult or a Promise of either; run may return those or a legacy RunResult, which is reported as before ("Run complete" / "Run failed: …"). Only void / { ok: true } (or a RunResult) counts as success and emits activity. { ok: false }, a rejection or a throw is the call's error, structuredContent { ok: false, op: "run" | "cancel", error, code? }, with no activity.
• Each gets a FlowRunContext as its last argument — { tool, agent, revision?, runId? }, captured when the tool was called and not recomputed — so the host can check authority and staleness: run(executors, context), cancel(context). runId is flow_cancel's optional argument.
• A run, cancel or run confirm pending when the bridge is disposed or replaced settles at once as "outcome unknown", and a late result is ignored. Closing the bridge never calls cancel: UI disposal is not a backend cancellation, so a durable run keeps going until your own code stops it.

cancel: async (context) => {
  const res = await api.post(`/runs/${context?.runId ?? currentRunId}/cancel`, { as: context?.agent.id });
  return res.ok ? { ok: true } : { ok: false, error: res.reason, code: res.code };
},

The flow bridge pushes no undo entries, with or without commit. As built: docs/flow-awaited-commits.md.

registerScreenDocBridge edits the nodes inside one screen and exports its DocAdapter, ScreenDocBridgeOptions, ScreenDocNode and ScreenDocOp types from @particle-academy/agent-integrations/bridges/screen-doc. The existing root import still works; nothing to do for existing consumers. Use a distinct surface tool prefix for each concurrently bridged document.

When you don't need an MCP server

If your agent runs in the same JS process as the surfaces it drives (an embedded chat widget, an in-page worker, an SSR-time tool loop), you don't need any of MCP's JSON-RPC framing. Use ToolRegistry — a plain in-memory tool host that the bridges register against. Agents drive the surface with host.callTool("sheet_set_cell", { … }) directly.

import {
  ToolRegistry,
  registerSheetsBridge,
  useSheetsAdapter,
} from "@particle-academy/agent-integrations";

const host = new ToolRegistry();
registerSheetsBridge(host, { adapter });

// in-process agent:
await host.callTool("sheet_set_cell", { address: "B3", value: 42 });

Need both? MicroMcpServer extends ToolRegistry, so the same instance serves direct in-process calls and SSE-relayed remote agents at the same time. Bridges accept either — every register*Bridge(host, …) signature takes a ToolHost.

A headless MCP server over stdio

For a Node process that an MCP client launches as a subprocess (Claude Code, Codex, Cursor, Claude Desktop), import the two headless subpaths. Neither reaches React or the DOM: /mcp imports no package at all, and /mcp/stdio imports only Node built-ins — a test walks both import graphs to keep it so.

import { MicroMcpServer } from "@particle-academy/agent-integrations/mcp";
import { attachStdio } from "@particle-academy/agent-integrations/mcp/stdio";

const server = new MicroMcpServer({
  info: { name: "my-server", version: "1.0.0" },
  // Newest first. initialize echoes the client's revision when it is listed,
  // and answers the first entry otherwise. Omit to answer MCP_PROTOCOL_VERSION.
  protocolVersions: ["2025-11-25", "2025-06-18", "2024-11-05"],
});
server.registerTool({ name: "hello", inputSchema: { type: "object" } }, () => ({
  content: [{ type: "text", text: "hi" }],
}));

attachStdio(server); // stdin/stdout; pass { input, output } for other streams

stdout carries protocol frames and nothing else — log to stderr. A line that is not a JSON-RPC message is reported through onError (stderr by default) and skipped rather than ending the session, and replies still in flight when stdin ends are delivered before the transport closes.

Import /mcp/stdio only from Node. Browser bundles import /mcp, which never pulls it in.

A tool name belongs to whoever registered it. registerTool throws when a name is already held by a different registrant, and the error names both. Pass { owner } to identify yourself: the same owner may register a name again (a React remount does), and every bridge already registers under its bridge id. Disposing frees the name. To take over another registrant's tool on purpose, pass { replace: true }.

server.registerTool(definition, handler, { owner: "support-triage" });

Connect an agent to your app — <ConnectorButtons>

The step before presence: getting your MCP server installed in the user's agent. <ConnectorButtons> renders the right "Add to Claude / Cursor / VS Code" affordance per client (each subtly different), and writeMcpbBundle() builds the Claude Desktop .mcpb:

import { ConnectorButtons } from "@particle-academy/agent-integrations";
import "@particle-academy/agent-integrations/styles.css";

<ConnectorButtons serverName="Decksmith" mcpUrl="https://decksmith.dev/mcp" mcpbDownloadUrl="/decksmith.mcpb" />

import { writeMcpbBundle } from "@particle-academy/agent-integrations/connectors/build"; // Node, build-time

Full guide + the per-client format gotchas: docs/connectors.md.

Architecture

┌─ Browser tab ───────────────────────────────────────┐
│   Whiteboard UI ── controlled state ── Bridge       │
│        ▲                                  │        │
│        │ tool calls mutate state          ▼        │
│        └────────── MicroMcpServer ◄─── Transport ◄─ │
│                                          ▲          │
└──────────────────────────────────────────┼──────────┘
                                           │
                                  ┌────────┴─────────┐
                                  │                  │
                           in-process            relay
                       (in-page agent)      (external agent
                                            via Reverb / WS)

• MicroMcpServer is a transport-agnostic JSON-RPC 2.0 / MCP protocol handler. Register tools, attach transports, done.
• InProcessTransport wires an in-page agent (e.g. an embedded Claude widget) to the server with zero serialization.
• RelayTransport wraps any JSON duplex channel (Reverb whisper, WebRTC data channel, SSE+POST tunnel) so external agents can reach the browser session.
• Bridges install a cohesive set of MCP tools against a host's controlled state. v0.1 ships the whiteboard bridge with the full tool kit.
• UI components (AgentPanel, AgentCursor, AgentActivityHighlight) make agent presence visible.

Quick start (in-page agent + whiteboard)

import {
  MicroMcpServer,
  attachInProcess,
  registerWhiteboardBridge,
  AgentPanel,
  AgentCursor,
  type AgentActivity,
} from "@particle-academy/agent-integrations";
import "@particle-academy/agent-integrations/styles.css";

function MyBoard() {
  const [notes, setNotes] = useState([]);
  const [shapes, setShapes] = useState([]);
  const [connectors, setConnectors] = useState([]);
  const [strokes, setStrokes] = useState([]);
  const [viewport, setViewport] = useState({ x: 0, y: 0, zoom: 1 });
  const [agentCursor, setAgentCursor] = useState(null);
  const [activity, setActivity] = useState<AgentActivity[]>([]);

  const serverRef = useRef<MicroMcpServer>();
  const transportRef = useRef<InProcessTransport>();

  useEffect(() => {
    const server = new MicroMcpServer({
      info: { name: "whiteboard-session", version: "0.1.0" },
    });
    const bridge = registerWhiteboardBridge(server, {
      adapter: {
        getNotes: () => notes, setNotes,
        getShapes: () => shapes, setShapes,
        getConnectors: () => connectors, setConnectors,
        getStrokes: () => strokes, setStrokes,
        getViewport: () => viewport, setViewport,
        setAgentCursor,
      },
    });
    const transport = attachInProcess(server);
    serverRef.current = server;
    transportRef.current = transport;
    return () => bridge.dispose();
  }, []);

  // ... render board, AgentPanel, AgentCursor when agentCursor is non-null ...
}

For an end-to-end runnable, see the sandbox demo at /whiteboard-agent (added in a follow-up PR).

External agent via relay

External MCP agents (Claude Code, Cursor, Claude Desktop, custom clients) reach a browser-hosted MicroMcpServer via a relay broker. The relay just shuttles JSON-RPC frames — it doesn't run tools or hold state.

Three ways to wire one up:

• docs/agent-hookable-demos.md — full end-to-end workflow (browser → relay → external agent), including a complete drop-in Laravel 10+ reference implementation (~200 LOC controller + routes + CSRF entry).
• docs/relay-server.md — the bundled Node relay (agent-integrations-relay bin, createNodeRelay() factory, Dockerfile). Use this when your site is not a Laravel/Rails/PHP app and you want a one-command deploy.
• docs/relay-protocol.md — the on-the-wire JSON envelope, with notes on the three transports the protocol supports (Reverb, WebRTC, SSE+POST).

The agent at the far end needs an MCP client. Beyond pasting the session URL into an existing one (Claude Code, Cursor, …), there's mcp-relay-client — a single-file, zero-dependency client (bash / Python / TS / Go) built for these relay sessions: curl -O …/connect.sh && bash connect.sh "<session-url>" tools.

Pattern (Reverb):

const channel = Echo.private(`agent.session.${id}`);
const transport = attachRelay(server, {
  sendToRemote: (frame) => channel.whisper("mcp", frame),
});
channel.listenForWhisper("mcp", (frame) => transport.deliverFromRemote(frame));

Agents (Claude Desktop, Cline, custom) connect to the same channel via your auth bridge.

Drive a page you don't own — ./dom-navigation

registerNavigationBridge (page_describe, page_read, page_click, page_set_field, nav_visit, …) needs an adapter that walks the page's DOM. ./dom-navigation ships that walker framework-free, in two halves:

• In the page: createDomNavigationAgent() — stable handles (data-co-handle → name → id → role#index), ARIA names, masking of sensitive values (password, cc-*, one-time-code, data-private), field writes that React-controlled inputs see, and rects. When your code does not run in the page, inject DOM_NAVIGATION_SCRIPT from ./dom-navigation/script instead: a self-contained IIFE (no module system) that installs globalThis.__fancyDomNavigation. Re-injecting is a no-op.
• In the host: createRemoteNavigationAdapter({ transport }) — a NavigationBridgeAdapter over any { call(method, args): Promise<unknown> }. Results from the page are coerced to the declared shapes; the page is hostile.

Electron, with the walker in an isolated world so the page cannot reach it:

import { DOM_NAVIGATION_SCRIPT } from "@particle-academy/agent-integrations/dom-navigation/script";
import { createRemoteNavigationAdapter, domNavigationCallScript } from "@particle-academy/agent-integrations/dom-navigation";
import { registerNavigationBridge } from "@particle-academy/agent-integrations/bridges/navigation";

const WORLD = 1001;
const wc = view.webContents;
const inject = () => wc.executeJavaScriptInIsolatedWorld(WORLD, [{ code: DOM_NAVIGATION_SCRIPT }]);
wc.on("dom-ready", inject); // every document needs its own copy

const adapter = createRemoteNavigationAdapter({
  transport: {
    call: (method, args) =>
      wc.executeJavaScriptInIsolatedWorld(WORLD, [{ code: domNavigationCallScript(method, args) }]),
  },
  confirm: (req) => askTheHuman(req), // without this, submits + destructive clicks are NOT staged
});
registerNavigationBridge(server, { adapter });

Adapter methods may return promises; the bridge awaits every call.

The page is treated as hostile all the way into the agent's context. The bridge renders every page-supplied string on one line, with control characters removed and the length capped, so a label cannot forge an extra action or heading line. A handle that could pass for action syntax is shown as a ~N alias, and every handle-taking tool maps it back. For read(), return a PageReadout ({ title, headings, text }) rather than a string. The bridge can then keep the outline one heading per line, while a plain string is rendered as one line.

Tools shipped (whiteboard bridge)

| Tool | Purpose | |---|---| | whiteboard_get_state | Full snapshot | | whiteboard_list_items | Summary of every item | | whiteboard_get_item | Detail by id | | whiteboard_add_sticky / _update_sticky | Sticky CRUD | | whiteboard_add_shape / _update_shape | Full shape kit (rect, rounded-rect, ellipse, diamond, triangle, line, arrow, text) | | whiteboard_add_connector | Connect two items / points | | whiteboard_add_stroke | Pen layer | | whiteboard_delete_item | Generic delete | | whiteboard_set_viewport | Pan / zoom | | whiteboard_set_agent_cursor | Move presence |

Security / host obligations

These bridges let an agent drive a human's terminal / files / editor / browser, so the host contract carries real weight. What the package does — and what it leaves to you:

• The MCP server is unauthenticated by design. MicroMcpServer does no per-tool auth — possession of the relay session token = permission to call every tool, including terminal_run. Put it behind an authenticating relay and treat the token as a password. The standalone ai-relay now binds 127.0.0.1 by default (pass --host 0.0.0.0 to expose, with a warning).
• Terminal is staged by default. registerTerminalBridge defaults pendingMode: true and does not expose terminal_confirm/terminal_reject as agent tools (an agent must not confirm its own command). Wire a human control to the returned bridge.confirm(id). terminal_write bytes are written verbatim (an embedded CR runs a command; ANSI/OSC reach the terminal) — set osc52={false} on any agent-driveable <Terminal> and gate writes like runs. { terminals } grants the agent every listed pane unless you pass canAccess.
• Files must be root-scoped by the host. Pass root to registerFilesBridge for a fail-closed string guard, but a host over a real filesystem MUST also realpath to defeat symlink/junction escapes — the bridge can't (it runs in the browser).
• Navigation / forms are trust-but-verify. nav_visit allows only http(s)/relative URLs; form_submit stages on adapter.confirm when pendingMode is on.
• Passkeys are management-only, and that is not a gap. registerPasskeyBridge exposes no tool that completes a WebAuthn ceremony — no passkey_authenticate, no passkey_sign_in — because a ceremony needs a user gesture and a biometric, and a tool that performed one would turn a phishing-resistant factor back into a bearer token. passkey_revoke stages a revoke for the human and has no confirm argument that would apply it (revoking the last passkey is a lockout). passkey_list re-projects onto the public summary fields, so handing it your ORM model cannot leak a public key, a user handle, or a signature counter.
• Activity reaches every peer; tool results reach the caller only if clients label themselves. Since 0.44.0 a reply goes only to the client that asked when clients send a client query parameter; unlabelled clients still get every frame. Notifications are always broadcast. The terminal bridge redacts raw command bytes from broadcast meta, but treat anything you return as visible to every holder of the token — don't return secrets.
• The relay serves SSE and long-poll. Behind Cloudflare (whose HTTP/3 edge resets long SSE streams) install @particle-academy/fancy-cf-relay so the browser polls; see docs/relay-server.md. Pass --cors a list of your sites' origins rather than leaving * on a public relay.

Status

v0.1 — protocol + whiteboard bridge + UI. APIs will evolve before v1.

License

MIT

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