paperclip/packages/plugins/sdk

@paperclipai/plugin-sdk

Official TypeScript SDK for Paperclip plugin authors.

• Worker SDK: @paperclipai/plugin-sdk — definePlugin, context, lifecycle
• UI SDK: @paperclipai/plugin-sdk/ui — React hooks and slot props
• Testing: @paperclipai/plugin-sdk/testing — in-memory host harness
• Bundlers: @paperclipai/plugin-sdk/bundlers — esbuild/rollup presets
• Dev server: @paperclipai/plugin-sdk/dev-server — static UI server + SSE reload

Reference: doc/plugins/PLUGIN_SPEC.md

Package surface

Import	Purpose
@paperclipai/plugin-sdk	Worker entry: definePlugin, runWorker, context types, protocol helpers
@paperclipai/plugin-sdk/ui	UI entry: hooks, host navigation, HTTP-safe clipboard copy, shared components, and slot prop types
@paperclipai/plugin-sdk/ui/hooks	Hooks only
@paperclipai/plugin-sdk/ui/types	UI types and slot prop interfaces
@paperclipai/plugin-sdk/testing	createTestHarness for unit/integration tests
@paperclipai/plugin-sdk/bundlers	createPluginBundlerPresets for worker/manifest/ui builds
@paperclipai/plugin-sdk/dev-server	startPluginDevServer, getUiBuildSnapshot
@paperclipai/plugin-sdk/protocol	JSON-RPC protocol types and helpers (advanced)
@paperclipai/plugin-sdk/types	Worker context and API types (advanced)

Manifest entrypoints

In your plugin manifest you declare:

• entrypoints.worker (required) — Path to the worker bundle (e.g. dist/worker.js). The host loads this and calls setup(ctx).
• entrypoints.ui (required if you use UI) — Path to the UI bundle directory. The host loads components from here for slots and launchers.

Install

pnpm add @paperclipai/plugin-sdk

Current deployment caveats

The SDK is stable enough for local development and first-party examples, but the runtime deployment model is still early.

• Plugin workers and plugin UI should both be treated as trusted code today.
• Plugin UI bundles run as same-origin JavaScript inside the main Paperclip app. They can call ordinary Paperclip HTTP APIs with the board session, so manifest capabilities are not a frontend sandbox.
• Local-path installs and the repo example plugins are development workflows. They assume the plugin source checkout exists on disk.
• For deployed plugins, publish an npm package and install that package into the Paperclip instance at runtime.
• The current host runtime expects a writable filesystem, npm available at runtime, and network access to the package registry used for plugin installation.
• Dynamic plugin install is currently best suited to single-node persistent deployments. Multi-instance cloud deployments still need a shared artifact/distribution model before runtime installs are reliable across nodes.
• The host ships a small shared React component kit through @paperclipai/plugin-sdk/ui. Use it for native Paperclip controls; custom React and CSS are still supported.
• ctx.assets is not part of the supported runtime in this build. Do not depend on asset upload/read APIs yet.

If you are authoring a plugin for others to deploy, treat npm-packaged installation as the supported path and treat repo-local example installs as a development convenience.

Worker quick start

import { definePlugin, runWorker } from "@paperclipai/plugin-sdk";

const plugin = definePlugin({
  async setup(ctx) {
    ctx.events.on("issue.created", async (event) => {
      ctx.logger.info("Issue created", { issueId: event.entityId });
    });

    ctx.data.register("health", async () => ({ status: "ok" }));
    ctx.actions.register("ping", async () => ({ pong: true }));

    ctx.tools.register("calculator", {
      displayName: "Calculator",
      description: "Basic math",
      parametersSchema: {
        type: "object",
        properties: { a: { type: "number" }, b: { type: "number" } },
        required: ["a", "b"]
      }
    }, async (params) => {
      const { a, b } = params as { a: number; b: number };
      return { content: `Result: ${a + b}`, data: { result: a + b } };
    });
  },
});

export default plugin;
runWorker(plugin, import.meta.url);

Note: runWorker(plugin, import.meta.url) must be called so that when the host runs your worker (e.g. node dist/worker.js), the RPC host starts and the process stays alive. When the file is imported (e.g. for tests), the main-module check prevents the host from starting.

Worker lifecycle and context

Lifecycle (definePlugin):

Hook	Purpose
setup(ctx)	Required. Called once at startup. Register event handlers, jobs, data/actions/tools, etc.
onHealth?()	Optional. Return { status, message?, details? } for health dashboard.
onConfigChanged?(newConfig)	Optional. Apply new config without restart; if omitted, host restarts worker.
onShutdown?()	Optional. Clean up before process exit (limited time window).
onValidateConfig?(config)	Optional. Return { ok, warnings?, errors? } for settings UI / Test Connection.
onWebhook?(input)	Optional. Handle POST /api/plugins/:pluginId/webhooks/:endpointKey; required if webhooks declared.

Context (ctx) in setup: config, localFolders, events, jobs, launchers, http, secrets, activity, state, entities, projects, companies, issues, agents, goals, access, authorization, data, actions, streams, tools, metrics, logger, manifest. Worker-side host APIs are capability-gated; declare capabilities in the manifest.

Agents: ctx.agents.invoke(agentId, companyId, opts) for one-shot invocation. ctx.agents.sessions for two-way chat: create, list, sendMessage (with streaming onEvent callback), close. See the Plugin Authoring Guide for details.

Jobs: Declare in manifest.jobs with jobKey, displayName, schedule (cron). Register handler with ctx.jobs.register(jobKey, fn). Webhooks: Declare in manifest.webhooks with endpointKey; handle in onWebhook(input). State: ctx.state.get/set/delete(scopeKey); scope kinds: instance, company, project, project_workspace, agent, issue, goal, run.

Trusted local folders: Declare manifest.localFolders[] and the local.folders capability when a plugin needs an operator-configured company-scoped folder. Use ctx.localFolders.configure(), status(), readText(), and writeTextAtomic() instead of resolving arbitrary filesystem paths yourself. The host validates absolute roots, read/write access, required relative folders/files, traversal attempts, symlink escapes, and writes through temp-file-plus-rename atomic replacement.

Events

Subscribe in setup with ctx.events.on(name, handler) or ctx.events.on(name, filter, handler). Emit plugin-scoped events with ctx.events.emit(name, companyId, payload) (requires events.emit).

Core domain events (subscribe with events.subscribe):

Event	Typical entity
company.created, company.updated	company
project.created, project.updated	project
project.workspace_created, project.workspace_updated, project.workspace_deleted	project_workspace
issue.created, issue.updated, issue.comment.created	issue
issue.document.created, issue.document.updated, issue.document.deleted	issue
issue.relations.updated, issue.checked_out, issue.released, issue.assignment_wakeup_requested	issue
agent.created, agent.updated, agent.status_changed	agent
agent.run.started, agent.run.finished, agent.run.failed, agent.run.cancelled	run
goal.created, goal.updated	goal
approval.created, approval.decided	approval
budget.incident.opened, budget.incident.resolved	budget_incident
cost_event.created	cost
activity.logged	activity

Plugin-to-plugin: Subscribe to plugin.<pluginId>.<eventName> (e.g. plugin.acme.linear.sync-done). Emit with ctx.events.emit("sync-done", companyId, payload); the host namespaces it automatically.

Filter (optional): Pass a second argument to on(): { projectId?, companyId?, agentId? } so the host only delivers matching events.

Company context: Events still carry companyId for company-scoped data, but plugin installation and activation are instance-wide in the current runtime. Access and authorization host services require an active company-scoped invocation such as an event, API route, tool run, environment call, or UI bridge call; the requested companyId must match that active scope.

Scheduled (recurring) jobs

Plugins can declare scheduled jobs that the host runs on a cron schedule. Use this for recurring tasks like syncs, digest reports, or cleanup.

1. Capability: Add jobs.schedule to manifest.capabilities.
2. Declare jobs in manifest.jobs: each entry has jobKey, displayName, optional description, and schedule (a 5-field cron expression).
3. Register a handler in setup() with ctx.jobs.register(jobKey, async (job) => { ... }).

Cron format (5 fields: minute, hour, day-of-month, month, day-of-week):

Field	Values	Example
minute	0–59	0, */15
hour	0–23	2, *
day of month	1–31	1, *
month	1–12	*
day of week	0–6 (Sun=0)	*, 1-5

Examples: "0 * * * *" = every hour at minute 0; "*/5 * * * *" = every 5 minutes; "0 2 * * *" = daily at 2:00.

Job handler context (PluginJobContext):

Field	Type	Description
jobKey	string	Matches the manifest declaration.
runId	string	UUID for this run.
trigger	"schedule" | "manual" | "retry"	What caused this run.
scheduledAt	string	ISO 8601 time when the run was scheduled.

Runs can be triggered by the schedule, manually from the UI/API, or as a retry (when an operator re-runs a job after a failure). Re-throw from the handler to mark the run as failed; the host records the failure. The host does not automatically retry—operators can trigger another run manually from the UI or API.

Example:

Manifest — include jobs.schedule and declare the job:

// In your manifest (e.g. manifest.ts):
const manifest = {
  // ...
  capabilities: ["jobs.schedule", "plugin.state.write"],
  jobs: [
    {
      jobKey: "heartbeat",
      displayName: "Heartbeat",
      description: "Runs every 5 minutes",
      schedule: "*/5 * * * *",
    },
  ],
  // ...
};

Worker — register the handler in setup():

ctx.jobs.register("heartbeat", async (job) => {
  ctx.logger.info("Heartbeat run", { runId: job.runId, trigger: job.trigger });
  await ctx.state.set({ scopeKind: "instance", stateKey: "last-heartbeat" }, new Date().toISOString());
});

UI slots and launchers

Slots are mount points for plugin React components. Launchers are host-rendered entry points (buttons, menu items) that open plugin UI. Declare slots in manifest.ui.slots with type, id, displayName, exportName; for context-sensitive slots add entityTypes. Declare launchers in manifest.ui.launchers (or legacy manifest.launchers).

Slot types / launcher placement zones

Slot types describe where a component mounts. Most values also exist as launcher placement zones.

Slot type / placement zone	Scope	Entity types (when context-sensitive)
page	Global	—
sidebar	Global	—
routeSidebar	Global	—
sidebarPanel	Global	—
settingsPage	Global	—
dashboardWidget	Global	—
globalToolbarButton	Global	—
detailTab	Entity	project, issue, agent, goal, run
taskDetailView	Entity	(task/issue context)
commentAnnotation	Entity	comment
commentContextMenuItem	Entity	comment
projectSidebarItem	Entity	project
toolbarButton	Entity	varies by host surface
contextMenuItem	Entity	varies by host surface

Scope describes whether the slot requires an entity to render. Global slots render without a specific entity but still receive the active companyId through PluginHostContext — use it to scope data fetches to the current company. Entity slots additionally require entityId and entityType (e.g. a detail tab on a specific issue).

Entity types (for entityTypes on slots): project | issue | agent | goal | run | comment. Full list: import PLUGIN_UI_SLOT_TYPES and PLUGIN_UI_SLOT_ENTITY_TYPES from @paperclipai/plugin-sdk.

Slot component descriptions

page

A full-page extension mounted at /plugins/:pluginId (global) or /:company/plugins/:pluginId (company-context route). Use this for rich, standalone plugin experiences such as dashboards, configuration wizards, or multi-step workflows. Receives PluginPageProps with context.companyId set to the active company. Requires the ui.page.register capability.

sidebar

Adds a navigation-style entry to the main company sidebar navigation area, rendered alongside the core nav items (Dashboard, Issues, Goals, etc.). Use this for lightweight, always-visible links or status indicators that feel native to the sidebar. Receives PluginSidebarProps with context.companyId set to the active company. Requires the ui.sidebar.register capability.

routeSidebar

A contextual sidebar shown while the current route is a plugin page route with the same routePath. Use this for full-page plugin workspaces that need their own local navigation. It does not replace the app sidebar: the host collapses the main <Sidebar/> to its 64px icon rail (still hover/peek-able) and renders your routeSidebar in a secondary pane beside it, producing [ app rail ][ your sidebar ][ content ]. Receives PluginRouteSidebarProps with context.companyId and context.companyPrefix set to the active company. Requires the ui.sidebar.register capability.

Do not mount RequestCollapsedSidebar (or otherwise try to collapse the app sidebar) from a routeSidebar plugin — the host drives the collapse automatically while your route is active and restores the user's preference when they navigate away. The collapse is a hard invariant: a secondary sidebar always forces the app rail collapsed (hiding its expand toggle), overriding any user pin, but it never mutates the user's saved expanded/collapsed preference — that is restored as soon as they leave your route.

sidebarPanel

Renders richer inline content in a dedicated panel area below the company sidebar navigation sections. Use this for mini-widgets, summary cards, quick-action panels, or at-a-glance status views that need more vertical space than a nav link. Receives context.companyId set to the active company via useHostContext(). Requires the ui.sidebar.register capability.

settingsPage

Replaces the auto-generated JSON Schema settings form with a custom React component. Use this when the default form is insufficient — for example, when your plugin needs multi-step configuration, OAuth flows, "Test Connection" buttons, or rich input controls. Receives PluginSettingsPageProps with context.companyId set to the active company. The component is responsible for reading and writing config through the bridge (via usePluginData and usePluginAction).

dashboardWidget

A card or section rendered on the main dashboard. Use this for at-a-glance metrics, status indicators, or summary views that surface plugin data alongside core Paperclip information. Receives PluginWidgetProps with context.companyId set to the active company. Requires the ui.dashboardWidget.register capability.

detailTab

An additional tab on a project, issue, agent, goal, or run detail page. Rendered when the user navigates to that entity's detail view. Receives PluginDetailTabProps with context.companyId set to the active company and context.entityId / context.entityType guaranteed to be non-null, so you can immediately scope data fetches to the relevant entity. Specify which entity types the tab applies to via the entityTypes array in the manifest slot declaration. Requires the ui.detailTab.register capability.

taskDetailView

A specialized slot rendered in the context of a task or issue detail view. Similar to detailTab but designed for inline content within the task detail layout rather than a separate tab. Receives context.companyId, context.entityId, and context.entityType like detailTab. Requires the ui.detailTab.register capability.

projectSidebarItem

A link or small component rendered once per project under that project's row in the sidebar Projects list. Use this to add project-scoped navigation entries (e.g. "Files", "Linear Sync") that deep-link into a plugin detail tab: /:company/projects/:projectRef?tab=plugin:<key>:<slotId>. Receives PluginProjectSidebarItemProps with context.companyId set to the active company, context.entityId set to the project id, and context.entityType set to "project". Use the optional order field in the manifest slot to control sort position. Requires the ui.sidebar.register capability.

globalToolbarButton

A button rendered in the global top bar (breadcrumb bar) that appears on every page. Use this for company-wide actions that are not scoped to a specific entity — for example, a universal search trigger, a global sync status indicator, or a floating action that applies across the whole workspace. Receives only context.companyId and context.companyPrefix; no entity context is available. Requires the ui.action.register capability.

toolbarButton

A button rendered in the toolbar of an entity page (e.g. project detail, issue detail). Use this for short-lived, contextual actions scoped to the current entity — like triggering a project sync, opening a picker, or running a quick command on that entity. The component can open a plugin-owned modal internally for confirmations or compact forms. Receives context.companyId, context.entityId, and context.entityType; declare entityTypes in the manifest to control which entity pages the button appears on. Requires the ui.action.register capability.

contextMenuItem

An entry added to a right-click or overflow context menu on a host surface. Use this for secondary actions that apply to the entity under the cursor (e.g. "Copy to Linear", "Re-run analysis"). Receives context.companyId set to the active company; entity context varies by host surface. Requires the ui.action.register capability.

commentAnnotation

A per-comment annotation region rendered below each individual comment in the issue detail timeline. Use this to augment comments with parsed file links, sentiment badges, inline actions, or any per-comment metadata. Receives PluginCommentAnnotationProps with context.entityId set to the comment UUID, context.entityType set to "comment", context.parentEntityId set to the parent issue UUID, context.projectId set to the issue's project (if any), and context.companyPrefix set to the active company slug. Requires the ui.commentAnnotation.register capability.

commentContextMenuItem

A per-comment context menu item rendered in the "more" dropdown menu (⋮) on each comment in the issue detail timeline. Use this to add per-comment actions such as "Create sub-issue from comment", "Translate", "Flag for review", or custom plugin actions. Receives PluginCommentContextMenuItemProps with context.entityId set to the comment UUID, context.entityType set to "comment", context.parentEntityId set to the parent issue UUID, context.projectId set to the issue's project (if any), and context.companyPrefix set to the active company slug. Plugins can open drawers, modals, or popovers scoped to that comment. The ⋮ menu button only appears on comments where at least one plugin renders visible content. Requires the ui.action.register capability.

Launcher actions and render options

Launcher action	Description
navigate	Navigate to a route (plugin or host).
openModal	Open a modal.
openDrawer	Open a drawer.
openPopover	Open a popover.
performAction	Run an action (e.g. call plugin).
deepLink	Deep link to plugin or external URL.

Render option	Values	Description
environment	hostInline, hostOverlay, hostRoute, external, iframe	Container the launcher expects after activation.
bounds	inline, compact, default, wide, full	Size hint for overlays/drawers.

Capabilities

Declare in manifest.capabilities. Grouped by scope:

Scope	Capability
Company	companies.read
	projects.read
	project.workspaces.read
	issues.read
	issue.comments.read
	issue.documents.read
	issue.relations.read
	issue.subtree.read
	agents.read
	goals.read
	goals.create
	goals.update
	activity.read
	costs.read
	issues.orchestration.read
	access.members.read
	access.invites.read
	authorization.grants.read
	authorization.policies.read
	authorization.audit.read
	database.namespace.read
	issues.create
	issues.update
	issues.checkout
	issues.wakeup
	issue.comments.create
	issue.comments.create_human_attributed
	issue.documents.write
	issue.relations.write
	activity.log.write
	metrics.write
	telemetry.track
	database.namespace.migrate
	database.namespace.write
	external.objects.detect
	external.objects.read
	external.objects.write
	external.objects.refresh
Instance	instance.settings.register
	plugin.state.read
	plugin.state.write
Runtime	events.subscribe
	events.emit
	jobs.schedule
	webhooks.receive
	api.routes.register
	http.outbound
	secrets.read-ref
	environment.drivers.register
	local.folders
Agent	agent.tools.register
	agents.invoke
	access.members.write
	access.invites.write
	authorization.grants.write
	authorization.policies.write
	agent.sessions.create
	agent.sessions.list
	agent.sessions.send
	agent.sessions.close
UI	ui.sidebar.register
	ui.page.register
	ui.detailTab.register
	ui.dashboardWidget.register
	ui.commentAnnotation.register
	ui.action.register

Full list in code: import PLUGIN_CAPABILITIES from @paperclipai/plugin-sdk.

External Object Reference Providers

Trusted connector plugins can declare generic external object providers in the manifest. The host owns URL scanning, sanitized canonical URLs, core storage, normalized status rendering, and issue/comment/document write durability. The plugin only identifies provider-owned objects and resolves board-safe status metadata.

objectReferences: [
  {
    providerKey: "mocktracker",
    displayName: "Mock Tracker",
    objectTypes: ["ticket"],
    urlPatterns: ["https://mock.example/tickets/:id"],
    refreshPolicy: { defaultTtlSeconds: 300, staleAfterSeconds: 1800 },
  },
],
capabilities: ["external.objects.detect", "external.objects.read"],

Implement onDetectExternalObjects() to map sanitized URL candidates to providerKey, objectType, provider-stable externalId, and optional display metadata such as displayKey/iconKey. Implement onResolveExternalObject() to return a normalized snapshot with statusCategory, statusTone, statusLabel, optional statusIconKey, board-safe data, and freshness metadata. Slow or failing plugins are isolated: Paperclip logs the failure and continues saving the source issue, comment, or document.

MVP security posture: provider plugins are trusted installs. Manifest capabilities gate host APIs and provider invocation paths, but they are not a sandbox boundary for untrusted marketplace code. Plugin UI is same-origin JavaScript and must not be mounted inline in markdown; inline external-object rendering uses host-owned metadata only. Treat untrusted providers as future work that requires worker sandboxing plus isolated plugin UI.

Restricted Database Namespace

Trusted orchestration plugins can declare a host-owned PostgreSQL namespace:

database: {
  migrationsDir: "migrations",
  coreReadTables: ["issues"],
}

Declare database.namespace.migrate and database.namespace.read; add database.namespace.write when the worker needs runtime writes. Migrations run before worker startup, are checksum-recorded, and may create or alter objects only inside the plugin namespace. Runtime ctx.db.query() allows SELECT from ctx.db.namespace plus manifest-whitelisted public core tables. Runtime ctx.db.execute() allows INSERT, UPDATE, and DELETE only against the plugin namespace.

Trusted Local Folders

Trusted local plugins can request operator-configured folders per company:

export const manifest = {
  // ...
  capabilities: ["local.folders"],
  localFolders: [
    {
      folderKey: "content-root",
      displayName: "Content root",
      access: "readWrite",
      requiredDirectories: ["sources", "pages"],
      requiredFiles: ["schema.md"],
    },
  ],
};

The host stores the selected path in company-scoped plugin settings and exposes readiness through:

• GET /api/plugins/:pluginId/companies/:companyId/local-folders
• GET /api/plugins/:pluginId/companies/:companyId/local-folders/:folderKey/status
• POST /api/plugins/:pluginId/companies/:companyId/local-folders/:folderKey/validate
• PUT /api/plugins/:pluginId/companies/:companyId/local-folders/:folderKey

Worker code should access files through ctx.localFolders.readText() and ctx.localFolders.writeTextAtomic(). Relative paths must stay inside the configured root; symlinks that escape the root are rejected.

Scoped API Routes

Manifest-declared apiRoutes expose JSON routes under /api/plugins/:pluginId/api/* without letting a plugin claim core paths:

apiRoutes: [
  {
    routeKey: "initialize",
    method: "POST",
    path: "/issues/:issueId/smoke",
    auth: "board-or-agent",
    capability: "api.routes.register",
    checkoutPolicy: "required-for-agent-in-progress",
    companyResolution: { from: "issue", param: "issueId" },
  },
]

Implement onApiRequest(input) in the worker to handle the route. The host performs auth, company access, capability, route matching, and checkout policy before dispatch. The worker receives route params, query, parsed JSON body, sanitized headers, actor context, and companyId; responses are JSON { status?, headers?, body? }.

Issue Orchestration APIs

Workflow plugins can use ctx.issues for orchestration-grade issue operations without importing host server internals.

Expanded create/update fields include blockers, billing code, board or agent assignees, labels, namespaced plugin origins, request depth, and safe execution workspace fields:

const child = await ctx.issues.create({
  companyId,
  parentId: missionIssueId,
  inheritExecutionWorkspaceFromIssueId: missionIssueId,
  title: "Implement feature slice",
  status: "todo",
  assigneeAgentId: workerAgentId,
  billingCode: "mission:alpha",
  originKind: "plugin:paperclip.missions:feature",
  originId: "mission-alpha:feature-1",
  blockedByIssueIds: [planningIssueId],
});

If originKind is omitted, the host stores plugin:<pluginKey>. Plugins may use sub-kinds such as plugin:<pluginKey>:feature, but the host rejects attempts to set another plugin's namespace.

Blocker relationships are also exposed as first-class helpers:

const relations = await ctx.issues.relations.get(child.id, companyId);
await ctx.issues.relations.setBlockedBy(child.id, [planningIssueId], companyId);
await ctx.issues.relations.addBlockers(child.id, [validationIssueId], companyId);
await ctx.issues.relations.removeBlockers(child.id, [planningIssueId], companyId);

Subtree reads can include just the issue tree, or compact related data for orchestration dashboards:

const subtree = await ctx.issues.getSubtree(missionIssueId, companyId, {
  includeRoot: true,
  includeRelations: true,
  includeDocuments: true,
  includeActiveRuns: true,
  includeAssignees: true,
});

Agent-run actions can assert checkout ownership before mutating in-progress work:

await ctx.issues.assertCheckoutOwner({
  issueId,
  companyId,
  actorAgentId: runCtx.agentId,
  actorRunId: runCtx.runId,
});

Plugins can request assignment wakeups through the host so budget stops, execution locks, blocker checks, and heartbeat policy still apply:

await ctx.issues.requestWakeup(child.id, companyId, {
  reason: "mission_advance",
  contextSource: "missions.advance",
});

await ctx.issues.requestWakeups([featureIssueId, validationIssueId], companyId, {
  reason: "mission_advance",
  contextSource: "missions.advance",
  idempotencyKeyPrefix: `mission:${missionIssueId}:advance`,
});

Use ctx.issues.summaries.getOrchestration() when a workflow needs compact reads across a root issue or subtree:

const summary = await ctx.issues.summaries.getOrchestration({
  issueId: missionIssueId,
  companyId,
  includeSubtree: true,
  billingCode: "mission:alpha",
});

By default, ctx.issues.createComment attributes the comment to the calling plugin's own agent (authorAgentId). A plugin that relays a message a human actually sent — a chat gateway bridging Slack/Telegram replies back onto an issue, for example — can instead attribute the comment to that person by passing actorUserId:

await ctx.issues.createComment(issueId, replyText, companyId, {
  actorUserId: verifiedSlackUser.paperclipUserId,
});

This requires the issue.comments.create_human_attributed capability in addition to issue.comments.create. The host independently verifies that actorUserId is an active human member of the issue's company before applying the comment — a plugin cannot forge attribution to an arbitrary or inactive user id. When the issue has a non-terminal status and an assigned agent, a human-attributed comment also wakes that assignee, the same way a board user's comment does in the web app.

Required capabilities:

API	Capability
ctx.issues.relations.get	issue.relations.read
ctx.issues.relations.setBlockedBy / addBlockers / removeBlockers	issue.relations.write
ctx.issues.getSubtree	issue.subtree.read
ctx.issues.assertCheckoutOwner	issues.checkout
ctx.issues.createComment	issue.comments.create
ctx.issues.createComment with actorUserId	issue.comments.create + issue.comments.create_human_attributed
ctx.issues.requestWakeup / requestWakeups	issues.wakeup
ctx.issues.summaries.getOrchestration	issues.orchestration.read

Plugin-originated mutations are logged with actorType: "plugin" and details fields sourcePluginId, sourcePluginKey, initiatingActorType, initiatingActorId, and initiatingRunId when a user or agent run initiated the plugin work.

UI quick start

import { usePluginData, usePluginAction } from "@paperclipai/plugin-sdk/ui";

export function DashboardWidget() {
  const { data } = usePluginData<{ status: string }>("health");
  const ping = usePluginAction("ping");
  return (
    <div style={{ display: "grid", gap: 8 }}>
      <strong>Health</strong>
      <div>{data?.status ?? "unknown"}</div>
      <button onClick={() => void ping()}>Ping</button>
    </div>
  );
}

Hooks reference

usePluginData<T>(key, params?)

Fetches data from the worker's registered getData handler. Re-fetches when params changes. Returns { data, loading, error, refresh }.

import { usePluginData } from "@paperclipai/plugin-sdk/ui";

interface SyncStatus {
  lastSyncAt: string;
  syncedCount: number;
  healthy: boolean;
}

export function SyncStatusWidget({ context }: PluginWidgetProps) {
  const { data, loading, error, refresh } = usePluginData<SyncStatus>("sync-status", {
    companyId: context.companyId,
  });

  if (loading) return <div>Loading…</div>;
  if (error) return <div>Error: {error.message}</div>;

  return (
    <div>
      <p>Status: {data!.healthy ? "Healthy" : "Unhealthy"}</p>
      <p>Synced {data!.syncedCount} items</p>
      <p>Last sync: {data!.lastSyncAt}</p>
      <button onClick={refresh}>Refresh</button>
    </div>
  );
}

usePluginAction(key)

Returns an async function that calls the worker's performAction handler. Throws PluginBridgeError on failure.

import { useState } from "react";
import { usePluginAction, type PluginBridgeError } from "@paperclipai/plugin-sdk/ui";

export function ResyncButton({ context }: PluginWidgetProps) {
  const resync = usePluginAction("resync");
  const [busy, setBusy] = useState(false);
  const [error, setError] = useState<string | null>(null);

  async function handleClick() {
    setBusy(true);
    setError(null);
    try {
      await resync({ companyId: context.companyId });
    } catch (err) {
      setError((err as PluginBridgeError).message);
    } finally {
      setBusy(false);
    }
  }

  return (
    <div>
      <button onClick={handleClick} disabled={busy}>
        {busy ? "Syncing..." : "Resync Now"}
      </button>
      {error && <p style={{ color: "red" }}>{error}</p>}
    </div>
  );
}

useHostContext()

Reads the active company, project, entity, and user context. Use this to scope data fetches and actions.

import { useHostContext, usePluginData } from "@paperclipai/plugin-sdk/ui";
import type { PluginDetailTabProps } from "@paperclipai/plugin-sdk/ui";

export function IssueLinearLink({ context }: PluginDetailTabProps) {
  const { companyId, entityId, entityType } = context;
  const { data } = usePluginData<{ url: string }>("linear-link", {
    companyId,
    issueId: entityId,
  });

  if (!data?.url) return <p>No linked Linear issue.</p>;
  return <a href={data.url} target="_blank" rel="noopener">View in Linear</a>;
}

useHostNavigation()

Routes Paperclip-internal plugin links through the host router without a full document reload. Use linkProps() for anchors so the browser still gets a real href for copy-link, modifier-click, middle-click, and open-in-new-tab behavior.

import { useHostNavigation } from "@paperclipai/plugin-sdk/ui";

export function WikiSidebarLink() {
  const hostNavigation = useHostNavigation();
  return <a {...hostNavigation.linkProps("/wiki")}>Wiki</a>;
}

linkProps("/wiki") resolves against the active company prefix, so in company PAP it renders href="/PAP/wiki". Already-prefixed paths such as /PAP/wiki are not prefixed again. For button-style commands, call hostNavigation.navigate("/issues/PAP-123").

Avoid raw same-origin hrefs or window.location.assign() for Paperclip-internal navigation from plugin UI. Those bypass the host router and can reload the whole app. External links should keep normal anchors with target="_blank" and rel="noopener noreferrer" as appropriate.

usePluginStream<T>(channel, options?)

Subscribes to a real-time event stream pushed from the plugin worker via SSE. The worker pushes events using ctx.streams.emit(channel, event) and the hook receives them as they arrive. Returns { events, lastEvent, connecting, connected, error, close }.

import { usePluginStream } from "@paperclipai/plugin-sdk/ui";

interface ChatToken {
  text: string;
}

export function ChatMessages({ context }: PluginWidgetProps) {
  const { events, connected, close } = usePluginStream<ChatToken>("chat-stream", {
    companyId: context.companyId ?? undefined,
  });

  return (
    <div>
      {events.map((e, i) => <span key={i}>{e.text}</span>)}
      {connected && <span className="pulse" />}
      <button onClick={close}>Stop</button>
    </div>
  );
}

The SSE connection targets GET /api/plugins/:pluginId/bridge/stream/:channel?companyId=.... The host bridge manages the EventSource lifecycle; close() terminates the connection.

UI authoring note

The host provides selected shared UI components through @paperclipai/plugin-sdk/ui. Plugins can also use normal React components, their own CSS, or small design primitives inside the plugin package.

Use copyTextToClipboard for every plugin copy action. The host selects the modern Clipboard API in secure contexts and a compatible fallback in plain-HTTP deployments.

import { copyTextToClipboard } from "@paperclipai/plugin-sdk/ui";

await copyTextToClipboard("text to copy");

Use the shared components when the plugin needs to look and behave like a native Paperclip surface:

Component	Use when
MarkdownBlock	Rendering markdown from plugin or host data
MarkdownEditor	Editing markdown with the host editor treatment
FileTree	Showing serializable workspace/wiki/import paths
IssuesList	Embedding a company-scoped native issue list
AssigneePicker	Selecting an agent or board user with the same picker as the new issue pane
ProjectPicker	Selecting a project with the same picker as the new issue pane
ManagedRoutinesList	Showing plugin-managed routines in settings UI

Shared Markdown Components

Plugin UI can render markdown and edit markdown using the same host components used by Paperclip issue comments and documents:

import { MarkdownBlock, MarkdownEditor } from "@paperclipai/plugin-sdk/ui";

export function WikiPageEditor() {
  const [body, setBody] = useState("# Wiki page");

  return (
    <>
      <MarkdownBlock content={body} />
      <MarkdownEditor value={body} onChange={setBody} bordered />
    </>
  );
}

MarkdownBlock can opt into Obsidian-style wikilinks when a plugin owns the target URL shape:

<MarkdownBlock
  content={"See [[wiki/entities/paperclip|Paperclip]]."}
  enableWikiLinks
  wikiLinkRoot="/wiki/page"
/>

Shared FileTree

Plugin UI can render the host file tree without importing host internals:

import { FileTree, type FileTreeNode } from "@paperclipai/plugin-sdk/ui";

const nodes: FileTreeNode[] = [
  { name: "AGENTS.md", path: "AGENTS.md", kind: "file", children: [] },
  {
    name: "wiki",
    path: "wiki",
    kind: "dir",
    children: [
      { name: "index.md", path: "wiki/index.md", kind: "file", children: [] },
    ],
  },
];

export function WikiFiles() {
  return (
    <FileTree
      nodes={nodes}
      expandedPaths={["wiki"]}
      selectedFile="wiki/index.md"
      onToggleDir={(path) => console.log("toggle", path)}
      onSelectFile={(path) => console.log("select", path)}
    />
  );
}

Shared Assignee and Project Pickers

Use AssigneePicker and ProjectPicker when a plugin needs to create, filter, or configure work against Paperclip entities. Both are controlled components and load their options from the host for the provided company.

import { AssigneePicker, ProjectPicker } from "@paperclipai/plugin-sdk/ui";

export function AssignmentControls({ companyId }: { companyId: string }) {
  const [assignee, setAssignee] = useState("");
  const [projectId, setProjectId] = useState("");

  return (
    <>
      <AssigneePicker
        companyId={companyId}
        value={assignee}
        onChange={(value, selection) => {
          setAssignee(value);
          console.log(selection.assigneeAgentId, selection.assigneeUserId);
        }}
      />
      <ProjectPicker
        companyId={companyId}
        value={projectId}
        onChange={setProjectId}
      />
    </>
  );
}

Slot component props

Each slot type receives a typed props object with context: PluginHostContext. Import from @paperclipai/plugin-sdk/ui.

Slot type	Props interface	context extras
page	PluginPageProps	—
sidebar	PluginSidebarProps	—
routeSidebar	PluginRouteSidebarProps	—
settingsPage	PluginSettingsPageProps	—
dashboardWidget	PluginWidgetProps	—
globalToolbarButton	PluginGlobalToolbarButtonProps	—
detailTab	PluginDetailTabProps	entityId: string, entityType: string
toolbarButton	PluginToolbarButtonProps	entityId: string, entityType: string
commentAnnotation	PluginCommentAnnotationProps	entityId: string, entityType: "comment", parentEntityId: string, projectId, companyPrefix
commentContextMenuItem	PluginCommentContextMenuItemProps	entityId: string, entityType: "comment", parentEntityId: string, projectId, companyPrefix
projectSidebarItem	PluginProjectSidebarItemProps	entityId: string, entityType: "project"

Example detail tab with entity context:

import type { PluginDetailTabProps } from "@paperclipai/plugin-sdk/ui";
import { usePluginData } from "@paperclipai/plugin-sdk/ui";

export function AgentMetricsTab({ context }: PluginDetailTabProps) {
  const { data, loading } = usePluginData<Record<string, string>>("agent-metrics", {
    agentId: context.entityId,
    companyId: context.companyId,
  });

  if (loading) return <div>Loading…</div>;
  if (!data) return <p>No metrics available.</p>;

  return (
    <dl>
      {Object.entries(data).map(([label, value]) => (
        <div key={label}>
          <dt>{label}</dt>
          <dd>{value}</dd>
        </div>
      ))}
    </dl>
  );
}

Launcher surfaces and modals

V1 does not provide a dedicated modal slot. Plugins can either:

• declare concrete UI mount points in ui.slots
• declare host-rendered entry points in ui.launchers

Supported launcher placement zones currently mirror the major host surfaces such as projectSidebarItem, globalToolbarButton, toolbarButton, detailTab, settingsPage, and contextMenuItem. Plugins may still open their own local modal from those entry points when needed.

Declarative launcher example:

{
  "ui": {
    "launchers": [
      {
        "id": "sync-project",
        "displayName": "Sync",
        "placementZone": "toolbarButton",
        "entityTypes": ["project"],
        "action": {
          "type": "openDrawer",
          "target": "sync-project"
        },
        "render": {
          "environment": "hostOverlay",
          "bounds": "wide"
        }
      }
    ]
  }
}

The host returns launcher metadata from GET /api/plugins/ui-contributions alongside slot declarations.

When a launcher opens a host-owned overlay or page, useHostContext(), usePluginData(), and usePluginAction() receive the current renderEnvironment through the bridge. Use that to tailor compact modal UI vs. full-page layouts without adding custom route parsing in the plugin.

Project sidebar item

Plugins can add a link under each project in the sidebar via the projectSidebarItem slot. This is the recommended slot-based launcher pattern for project-scoped workflows because it can deep-link into a richer plugin tab. The component is rendered once per project with that project’s id in context.entityId. Declare the slot and capability in your manifest:

{
  "ui": {
    "slots": [
      {
        "type": "projectSidebarItem",
        "id": "files",
        "displayName": "Files",
        "exportName": "FilesLink",
        "entityTypes": ["project"]
      }
    ]
  },
  "capabilities": ["ui.sidebar.register", "ui.detailTab.register"]
}

Minimal React component that links to the project’s plugin tab (see project detail tabs in the spec):

import {
  useHostNavigation,
  type PluginProjectSidebarItemProps,
} from "@paperclipai/plugin-sdk/ui";

export function FilesLink({ context }: PluginProjectSidebarItemProps) {
  const hostNavigation = useHostNavigation();
  const projectId = context.entityId;
  const projectRef = projectId; // or resolve from host; entityId is project id
  return (
    <a {...hostNavigation.linkProps(`/projects/${projectRef}?tab=plugin:your-plugin:files`)}>
      Files
    </a>
  );
}

Use optional order in the slot to sort among other project sidebar items. See §19.5.1 in the plugin spec and project detail plugin tabs (§19.3) for the full flow.

Toolbar launcher with a local modal

Two toolbar slot types are available depending on where the button should appear:

• globalToolbarButton — renders in the top bar on every page, scoped to the company. No entity context. Use for workspace-wide actions.
• toolbarButton — renders on entity detail pages (project, issue, etc.). Receives entityId and entityType. Declare entityTypes to control which pages the button appears on.

For short-lived actions, mount the appropriate slot type and open a plugin-owned modal inside the component. Use useHostContext() to scope the action to the current company or entity.

Project-scoped example (appears only on project detail pages):

{
  "ui": {
    "slots": [
      {
        "type": "toolbarButton",
        "id": "sync-toolbar-button",
        "displayName": "Sync",
        "exportName": "SyncToolbarButton",
        "entityTypes": ["project"]
      }
    ]
  },
  "capabilities": ["ui.action.register"]
}

import { useState } from "react";
import {
  useHostContext,
  usePluginAction,
} from "@paperclipai/plugin-sdk/ui";

export function SyncToolbarButton() {
  const context = useHostContext();
  const syncProject = usePluginAction("sync-project");
  const [open, setOpen] = useState(false);
  const [submitting, setSubmitting] = useState(false);
  const [errorMessage, setErrorMessage] = useState<string | null>(null);

  async function confirm() {
    if (!context.projectId) return;
    setSubmitting(true);
    setErrorMessage(null);
    try {
      await syncProject({ projectId: context.projectId });
      setOpen(false);
    } catch (err) {
      setErrorMessage(err instanceof Error ? err.message : "Sync failed");
    } finally {
      setSubmitting(false);
    }
  }

  return (
    <>
      <button type="button" onClick={() => setOpen(true)}>
        Sync
      </button>
      {open ? (
        <div
          role="dialog"
          aria-modal="true"
          className="fixed inset-0 z-50 flex items-center justify-center bg-black/40 p-4"
          onClick={() => !submitting && setOpen(false)}
        >
          <div
            className="w-full max-w-md rounded-lg bg-background p-4 shadow-xl"
            onClick={(event) => event.stopPropagation()}
          >
            <h2 className="text-base font-semibold">Sync this project?</h2>
            <p className="mt-2 text-sm text-muted-foreground">
              Queue a sync for <code>{context.projectId}</code>.
            </p>
            {errorMessage ? (
              <p className="mt-2 text-sm text-destructive">{errorMessage}</p>
            ) : null}
            <div className="mt-4 flex justify-end gap-2">
              <button type="button" onClick={() => setOpen(false)}>
                Cancel
              </button>
              <button type="button" onClick={() => void confirm()} disabled={submitting}>
                {submitting ? "Running…" : "Run sync"}
              </button>
            </div>
          </div>
        </div>
      ) : null}
    </>
  );
}

Prefer deep-linkable tabs and pages for primary workflows. Reserve plugin-owned modals for confirmations, pickers, and compact editors.

Real-time streaming (ctx.streams)

Plugins can push real-time events from the worker to the UI using server-sent events (SSE). This is useful for streaming LLM tokens, live sync progress, or any push-based data.

Worker side

In setup(), use ctx.streams to open a channel, emit events, and close when done:

const plugin = definePlugin({
  async setup(ctx) {
    ctx.actions.register("chat", async (params) => {
      const companyId = params.companyId as string;
      ctx.streams.open("chat-stream", companyId);

      for await (const token of streamFromLLM(params.prompt as string)) {
        ctx.streams.emit("chat-stream", { text: token });
      }

      ctx.streams.close("chat-stream");
      return { ok: true };
    });
  },
});

API:

Method	Description
ctx.streams.open(channel, companyId)	Open a named stream channel and associate it with a company. Sends a streams.open notification to the host.
ctx.streams.emit(channel, event)	Push an event to the channel. The companyId is automatically resolved from the prior open() call.
ctx.streams.close(channel)	Close the channel and clear the company mapping. Sends a streams.close notification.

Stream notifications are fire-and-forget JSON-RPC messages (no id field). They are sent via notifyHost() synchronously during handler execution.

UI side

Use the usePluginStream hook (see Hooks reference above) to subscribe to events from the UI.

Host-side architecture

The host maintains an in-memory PluginStreamBus that fans out worker notifications to connected SSE clients:

1. Worker emits streams.emit notification via stdout
2. Host (plugin-worker-manager) receives the notification and publishes to PluginStreamBus
3. SSE endpoint (GET /api/plugins/:pluginId/bridge/stream/:channel?companyId=...) subscribes to the bus and writes events to the response

The bus is keyed by pluginId:channel:companyId, so multiple UI clients can subscribe to the same stream independently.

Streaming agent responses to the UI

ctx.streams and ctx.agents.sessions are complementary. The worker sits between them, relaying agent events to the browser in real time:

UI ──usePluginAction──▶ Worker ──sessions.sendMessage──▶ Agent
UI ◀──usePluginStream── Worker ◀──onEvent callback────── Agent

The agent doesn't know about streams — the worker decides what to relay. Encode the agent ID in the channel name to scope streams per agent.

Worker:

ctx.actions.register("ask-agent", async (params) => {
  const { agentId, companyId, prompt } = params as {
    agentId: string; companyId: string; prompt: string;
  };

  const channel = `agent:${agentId}`;
  ctx.streams.open(channel, companyId);

  const session = await ctx.agents.sessions.create(agentId, companyId);

  await ctx.agents.sessions.sendMessage(session.sessionId, companyId, {
    prompt,
    onEvent: (event) => {
      ctx.streams.emit(channel, {
        type: event.eventType,       // "chunk" | "done" | "error"
        text: event.message ?? "",
      });
    },
  });

  ctx.streams.close(channel);
  return { sessionId: session.sessionId };
});

UI:

import { useState } from "react";
import { usePluginAction, usePluginStream } from "@paperclipai/plugin-sdk/ui";

interface AgentEvent {
  type: "chunk" | "done" | "error";
  text: string;
}

export function AgentChat({ agentId, companyId }: { agentId: string; companyId: string }) {
  const askAgent = usePluginAction("ask-agent");
  const { events, connected, close } = usePluginStream<AgentEvent>(`agent:${agentId}`, { companyId });
  const [prompt, setPrompt] = useState("");

  async function send() {
    setPrompt("");
    await askAgent({ agentId, companyId, prompt });
  }

  return (
    <div>
      <div>{events.filter(e => e.type === "chunk").map((e, i) => <span key={i}>{e.text}</span>)}</div>
      <input value={prompt} onChange={(e) => setPrompt(e.target.value)} />
      <button onClick={send}>Send</button>
      {connected && <button onClick={close}>Stop</button>}
    </div>
  );
}

Agent sessions (two-way chat)

Plugins can hold multi-turn conversational sessions with agents:

// Create a session
const session = await ctx.agents.sessions.create(agentId, companyId);

// Send a message and stream the response
await ctx.agents.sessions.sendMessage(session.sessionId, companyId, {
  prompt: "Help me triage this issue",
  onEvent: (event) => {
    if (event.eventType === "chunk") console.log(event.message);
    if (event.eventType === "done") console.log("Stream complete");
  },
});

// List active sessions
const sessions = await ctx.agents.sessions.list(agentId, companyId);

// Close when done
await ctx.agents.sessions.close(session.sessionId, companyId);

Requires capabilities: agent.sessions.create, agent.sessions.list, agent.sessions.send, agent.sessions.close.

Exported types: AgentSession, AgentSessionEvent, AgentSessionSendResult, PluginAgentSessionsClient.

Testing utilities

import { createTestHarness } from "@paperclipai/plugin-sdk/testing";
import plugin from "../src/worker.js";
import manifest from "../src/manifest.js";

const harness = createTestHarness({ manifest });
await plugin.definition.setup(harness.ctx);
await harness.emit("issue.created", { issueId: "iss_1" }, { entityId: "iss_1", entityType: "issue" });

Bundler presets

import { createPluginBundlerPresets } from "@paperclipai/plugin-sdk/bundlers";

const presets = createPluginBundlerPresets({ uiEntry: "src/ui/index.tsx" });
// presets.esbuild.worker / presets.esbuild.manifest / presets.esbuild.ui
// presets.rollup.worker / presets.rollup.manifest / presets.rollup.ui

Local dev server (hot-reload events)

paperclip-plugin-dev-server --root . --ui-dir dist/ui --port 4177

Or programmatically:

import { startPluginDevServer } from "@paperclipai/plugin-sdk/dev-server";
const server = await startPluginDevServer({ rootDir: process.cwd() });

Dev server endpoints:

• GET /__paperclip__/health returns { ok, rootDir, uiDir }
• GET /__paperclip__/events streams reload SSE events on UI build changes