Paperclip Plugin Development

Build Paperclip plugins based on the actual SDK source code, validator source code, and examples. Follows lessons learned from real publishing failures.

Critical Lessons — Read First

These mistakes have cost real time. Do not repeat them.

1. files field in package.json is REQUIRED

npm uses .gitignore to exclude files. Since dist/ is gitignored, built output will be absent unless explicitly declared:

{ "files": ["dist", "package.json"] }

2. Capabilities must exactly match declared features

The server rejects manifests where features lack matching capabilities. Every UI slot type, tool, job, and webhook requires a specific capability. See references/manifest-reference.md for the full mapping table.

Example: declaring a dashboardWidget slot without ui.dashboardWidget.register in capabilities causes install failure.

3. First publish version: 0.0.1

The scaffold generates 0.1.0. Change to 0.0.1 before first publish.

4. Build before publish

paperclipPlugin fields point to ./dist/. Run bun run build before npm publish. Verify with npm pack --dry-run.

5. npm cache on the Paperclip server

When iterating, clear stale cache on the server: npm cache clean --force via SSH.

6. Adding capabilities triggers upgrade approval

Publishing a new version with additional capabilities puts the plugin in upgrade_pending state. Plan v1 capabilities carefully.

7. No agents.create in SDK

The plugin SDK can read, pause, resume, invoke, and chat with agents — but cannot create or update them. For v1, present templates in the UI and let the operator create agents manually.

8. ConvexError stores messages in error.data, NOT error.message

When catching errors from Convex mutations in Next.js API routes, error.message is always the generic "[Request ID: xxx] Server Error". The actual user-facing message is in error.data. Use this pattern:

import { ConvexError } from "convex/values";

function extractConvexErrorMessage(error: unknown): string {
  if (error instanceof ConvexError) {
    const data = error.data;
    if (typeof data === "string") return data;
    if (data && typeof data === "object" && "message" in data) {
      return String((data as { message: unknown }).message);
    }
    return JSON.stringify(data);
  }
  if (error instanceof Error) return error.message;
  return String(error);
}

9. SDK tgz files go stale when upstream Paperclip changes shared types

When upstream Paperclip adds new fields to shared types (like originKind on Issue), the plugin SDK tgz files become stale. To rebuild:

cd ~/code/paperclip/packages/shared && pnpm run build && pnpm pack
cd ~/code/paperclip/packages/plugins/sdk && pnpm run build && pnpm pack
# Copy both .tgz files to plugin's .paperclip-sdk/ directory
# Delete pnpm-lock.yaml (integrity hashes are cached)
bun install

10. ctx.http.fetch does NOT support relative URLs or private IPs

Plugin workers cannot call the internal Paperclip API via ctx.http.fetch — it blocks private IPs and requires absolute URLs. Use the typed SDK clients instead: ctx.issues.list, ctx.agents.list, etc. There is no ctx.routines client.

Scaffolding

node ~/code/paperclip/packages/plugins/create-paperclip-plugin/src/index.ts \
  <package-name> \
  --output <dir> \
  --display-name "<Name>" \
  --description "<text>" \
  --author "<name>" \
  --category connector|workspace|automation|ui \
  --sdk-path ~/code/paperclip/packages/plugins/sdk

Immediately after scaffolding:

1. Add "files": ["dist", "package.json"] to package.json
2. Change version to "0.0.1"
3. Init git, commit

Worker — Quick Overview

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

const plugin = definePlugin({
  async setup(ctx) {
    ctx.events.on("issue.created", async (event) => { ... });
    ctx.jobs.register("my-sync", async (job) => { ... });
    ctx.data.register("health", async (params) => ({ status: "ok" }));
    ctx.actions.register("resync", async (params) => { ... });
    ctx.tools.register("my-tool", { displayName: "...", description: "...", parametersSchema: { ... } },
      async (params, runCtx) => ({ content: "result" }));
  },
  async onHealth() { return { status: "ok" }; },
});

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

For the full PluginContext API: read references/worker-api-reference.md.

UI — Quick Overview

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

export function DashboardWidget() {
  const { companyId } = useHostContext();
  const { data, loading, error, refresh } = usePluginData<T>("health", { companyId });
  const doAction = usePluginAction("resync");
  if (loading) return <div>Loading...</div>;
  return <div>Status: {data?.status}</div>;
}

For all hooks, props, patterns, and styling: read references/ui-reference.md.

Publishing Checklist

[ ] bun run build
[ ] "files": ["dist", "package.json"] in package.json
[ ] Version is correct (0.0.1 for first publish)
[ ] Every declared slot type has matching capability
[ ] tools[] → "agent.tools.register", jobs[] → "jobs.schedule", webhooks[] → "webhooks.receive"
[ ] npm pack --dry-run — verify dist/ appears
[ ] bun run test passes
[ ] Use Skill(bopen-tools:npm-publish) for publishing

Installing in Paperclip

Enter the npm package name (e.g., @bopen-io/tortuga-plugin) in the "Install Plugin" dialog in Settings → Plugins. The server downloads from npm, validates the manifest, and starts the worker.

Naming Conventions

• Slot IDs: "<plugin-slug>-<slot-type>" — e.g., "tortuga-dashboard-widget"
• Export names: PascalCase — "DashboardWidget", "FleetPage"
• Job/webhook/tool/data/action/stream keys: kebab-case — "clawnet-sync", "fleet-status"
• Collect all strings in a constants.ts file

Sandbox Constraints

Plugin workers run in a vm.createContext() sandbox. No access to process, require, fs, net, child_process. CJS bundles only (esbuild presets handle this). All host interaction through PluginContext methods.

Secrets

Declare format: "secret-ref" in instanceConfigSchema. Operator pastes a secret UUID. Resolve at runtime: await ctx.secrets.resolve(config.apiKey). Never cache resolved values.

Reference Files

For detailed API documentation, consult:

• references/manifest-reference.md — All 37 capabilities, slot types, validation rules, declaration examples
• references/worker-api-reference.md — Full PluginContext API, lifecycle hooks, sandbox constraints
• references/ui-reference.md — All 5 hooks, component props, styling, streaming, navigation patterns

Source Code References

• Plugin SDK: ~/code/paperclip/packages/plugins/sdk/
• Plugin spec: ~/code/paperclip/doc/plugins/PLUGIN_SPEC.md
• Kitchen sink example: ~/code/paperclip/packages/plugins/examples/plugin-kitchen-sink-example/
• Hello world example: ~/code/paperclip/packages/plugins/examples/plugin-hello-world-example/
• File browser example: ~/code/paperclip/packages/plugins/examples/plugin-file-browser-example/
• Scaffolding tool: ~/code/paperclip/packages/plugins/create-paperclip-plugin/
• Capability validator: ~/code/paperclip/server/src/services/plugin-capability-validator.ts
• Manifest validator: ~/code/paperclip/server/src/services/plugin-manifest-validator.ts
• Tortuga plugin: ~/code/tortuga-plugin/
• Tortuga architecture: ~/code/tortuga-plugin/ARCHITECTURE.md