paseo-plugin-devkit

Docs site · Getting started · Commands · Fake agent · Safety model

Test, verify and ship Paseo plugins without touching your real Paseo.

ppd is a CLI, a set of vitest helpers and a Claude Code skill. One command gives you an isolated dev daemon, another checks your plugin against the host's runtime rules, others drive the web UI, an Android phone, releases and the registry.

An unofficial community project, not affiliated with or endorsed by the Paseo team.

Why

Built while shipping a real plugin (a PDF and Office viewer). Each of these cost days, and each is now a check, a guard or one command:

• Hand-built isolated daemons. Testing a plugin means a temp home, a free port, plugins and the web UI on, relay off. One wrong flag and you restart or reconfigure your real daemon on port 6767. ppd daemon up does it safely in one line.
• Host-contract surprises found late. An icon name the app's Lucide build lacks makes the button silently vanish. class syntax in a dependency passes on web and crashes on phones (Hermes). A module the host does not provide throws only at load. ppd check finds these before install.
• Registry submission gotchas. Issues filed with gh issue create miss the submission label and are ignored. Git listings never get automatic update PRs. The validator fails on macOS temp paths. ppd registry handles all three.
• Device testing friction. adb reverse, which device, is the phone unlocked, and never pressing keys on someone's phone. ppd android up connects it and reports state, read-only.

Quick start

Requires Node 22.18+ and, for the daemon commands, the Paseo CLI (the desktop app ships it).

Start a new plugin:

npx --package paseo-plugin-devkit ppd create ~/code/my-plugin    # panel template: workspace panel + one RPC
cd ~/code/my-plugin && npm install
npm run check && npm test                                         # ppd check, unit tests, host-contract suite
npx ppd daemon up --workspace ~/code/my-plugin                    # isolated dev daemon
npx ppd dev                                                       # install, reload on every change
npx ppd daemon down

--template agent-hook gives a turn_ended hook with a timeline card instead; start its daemon with --fake-agent. Inside the plugin, npx ppd runs the devkit that create added as a devDependency. Outside a project, always write npx --package paseo-plugin-devkit ppd ...: the npm name ppd belongs to an unrelated package.

ppd create runs paseo plugin init (SDK versions matching your Paseo) and adds what init leaves out: tsconfig node types, an @types/node ~22 pin, .gitignore, vitest, npm run check, a README. The result passes ppd check and installs as is. The devkit dependency is the npm release that created the plugin (^0.1.0); pass --devkit file:/path/to/clone for a local checkout.

Add it to an existing plugin:

npm install -D paseo-plugin-devkit
npx ppd check                                     # plugin in cwd

Try it on the bundled example plugin:

git clone https://github.com/nkwib/paseo-plugin-devkit.git
cd paseo-plugin-devkit
npm ci                                   # installs and builds
npx ppd doctor                           # what is installed, what is missing
npx ppd check examples/hello-plugin      # host-contract checks with the installed Paseo app's compiler
npx ppd registry precheck examples/hello-plugin

# needs the Paseo CLI:
npx ppd daemon up --workspace /tmp/demo-workspace
npx ppd install examples/hello-plugin    # rerun after edits, or: npx ppd dev examples/hello-plugin
npx ppd web --command "Open Hello panel" --click Greet --shot out/hello.png
npx ppd daemon down

ppd check compiles and evaluates with the installed Paseo app's own compiler and evaluator, and checks icon names against the app's Lucide set (read from app.asar and the web bundle in Paseo.app/Contents/Resources). Order: PASEO_SOURCE (a getpaseo/paseo checkout with npm ci done, to test against unreleased Paseo), then the app (--paseo-app, PASEO_APP, the app behind paseo on PATH, /Applications/Paseo.app), then an esbuild replica. Replica results are labeled APPROXIMATION; --approx forces it.

Demo

Real output from the commands above (temp path shortened):

$ npx ppd check examples/hello-plugin
PASS  manifest         hello-plugin, requires paseo >=0.11.2
PASS  imports          client, server and shared boundaries hold
PASS  dependencies     no runtime packages
PASS  paseo-compile    compilePlugin of the Paseo 0.11.4 app (/Applications/Paseo.app) accepted the plugin
PASS  client-requires  client requires only host modules (@getpaseo/plugin, @getpaseo/plugin/client, react, react-native, react/jsx-runtime, zod)
PASS  server-requires  server requires only host modules and Node built-ins
PASS  server-eval      Paseo's evaluator ran the contribution in 0 ms; RPCs: hello.greet
PASS  client-eval      contributions: addWorkspacePanel, addCommandCenterItem
PASS  hermes-class     no class syntax in the client bundle
SKIP  hermes-parse     hermesc not found (install react-native as a devDependency, or set HERMESC)
SKIP  hermes-vm        Hermes VM not found (react-native ships it for macOS; or set HERMES)
PASS  lucide-icons     2 icon name(s) valid against 6354 Lucide icons of the Paseo 0.11.4 app (/Applications/Paseo.app)
PASS  bundle-size      client 5 KiB (2 KiB gzip), budget 2.0 MiB; server 2 KiB (1 KiB gzip), eval 0 ms, budget 32.0 MiB

11 passed, 0 warnings, 0 failed, 2 skipped

$ npx ppd daemon up --workspace /tmp/demo-workspace
dev daemon "default" up
  url:   http://127.0.0.1:7800
  home:  $TMPDIR/ppd-default-aiOmq4
  pid:   51399
  paseo: 0.11.4
workspace created for /tmp/demo-workspace

$ npx ppd install examples/hello-plugin    # rerun after edits, or: npx ppd dev examples/hello-plugin
installing examples/hello-plugin as hello-plugin into http://127.0.0.1:7800
hello-plugin: running (installed)
client: passes the app's registration rules
--- plugin logs
TIME                      STREAM    MESSAGE
2026-10-17T18:11:21.230Z  stdout    [paseo] Loading plugin
2026-10-17T18:11:21.477Z  stdout    [paseo] Plugin ready

$ npx ppd web --command "Open Hello panel" --click Greet --shot out/hello.png
opened workspace demo-workspace (wks_ef7618d24d59ccb1)
screenshot: out/hello.png
console errors: none
plugin evaluation errors: none

$ npx ppd daemon down
stopped dev daemon "default" (pid 51399)
removed $TMPDIR/ppd-default-aiOmq4

The screenshot ppd web took: the example's panel, served by the isolated daemon, after its RPC round trip.

Commands

Every command has ppd <command> --help.

| Command | What it does | | --- | --- | | ppd create <dir> | New plugin that passes ppd check and installs as is. --template panel (default: workspace panel, Command Center item, one RPC) or agent-hook (server.on("agent.turn_ended") appends a timeline card; client renderer and a screen it opens). Wraps paseo plugin init, built-in base without it (--no-init). --id, --name, --devkit. | | ppd doctor | Node, Paseo CLI and version, web UI build, check compiler (app or checkout), browser, Hermes, adb, Xcode, gh, disk, running dev daemons. | | ppd daemon up | Detached daemon in a fresh home under $TMPDIR on a free port (7800-7899): plugins and web UI on; relay, MCP and speech off. --workspace DIR, --port, --name, --caffeinate, --fake-agent (installs the scripted provider below). | | ppd daemon down / status | Stops the daemon and removes its home / shows it with installed plugins. | | ppd install [dir] | Installs a plugin into the dev daemon, or reloads (same directory) or replaces an installed one, so rerun it after edits. Checks the client against the app's registration rules: an unknown icon or bad id makes the app drop the whole client with only a console warning, so ppd install reports client-rejected and exits 1. --git installs committed HEAD through the manifest build, like a registry install; a plugin in a repo subfolder is installed with --path. | | ppd dev [dir] | Installs, then watches: every change reloads the plugin (paseo plugin reload), re-checks the client and prints the result; plugin log lines stream as they appear. | | ppd paseo -- <args> | Any Paseo CLI call against the dev daemon, e.g. plugin reload <id>, plugin logs <id>. | | ppd web | Web UI in Chrome via Playwright: opens the workspace, prints console errors and plugin clients the app failed to evaluate (exit 1 if a client failed). --shot, --viewport 390x844, --command "<Command Center item>", --click "<aria label>", --headed. | | ppd android up\|down\|status | adb reverse to the dev daemon for a phone running the Paseo app. Read-only device checks (lock, screen, foreground app). | | ppd check [dir] | Host-contract checks, below. --json, --paseo-app, --paseo-source, --approx, --max-client-kb, --max-server-kb. | | ppd registry precheck | OVERVIEW.md lint, media and icon paths, lockfile sync, build sanity, listing files committed. | | ppd registry submit | Prints the prefilled registry form URL (a tree/<ref>/<path> URL for a plugin in a repo subfolder) and what to verify after. | | ppd registry update --registry <fork> | Record-edit branch for a Git release in your registry fork, runs the validator, prints push and PR commands. --yes runs them. | | ppd release <patch\|minor\|major\|X.Y.Z> | Checks the remote first (origin exists, tag not on origin, git push --dry-run passes), then bumps, writes the changelog section, commits, tags, pushes and creates the GitHub release. Rerun after a failed push resumes from the push. --dry-run prints the commands. |

What ppd check verifies

| Check | How | | --- | --- | | Compile | Paseo's own compilePlugin, from the installed app or PASEO_SOURCE; an esbuild replica (labeled APPROXIMATION) only when neither is found. Compile errors carry file:line:col. | | Client modules | Bundle requires only host-provided modules; no gesture handler, reanimated, safe-area or Lucide imports. | | Server bundle | Requires only host modules and Node built-ins; evaluated in a child process (Paseo's evaluator inside the 120 s compile step with the app or a checkout, a replica with a 30 s limit on the approximation); registered RPCs listed; the returned cleanup is called and handles it leaves open (servers, timers) are warnings. A process.exit or a hang fails. | | Client eval | Factory runs in a child process against stub host modules, with the app's registration rules: ids, contexts, callbacks, duplicates, icons, cleanup. Any violation fails, because the app then drops the whole client. | | Hermes | No class syntax; hermesc parse and a smoke run in the Hermes VM when the binaries are found. | | Icons | Every contribution icon exists in the app's Lucide set (read from the app bundle). | | Size, deps, boundaries | Bundle sizes, runtime deps in dependencies, client/server import boundaries, @types/node range. |

In your test suite

// test/host-contract.test.ts: one vitest test per check
import { fileURLToPath } from "node:url";
import { describeHostContract } from "paseo-plugin-devkit/vitest";

describeHostContract(fileURLToPath(new URL("..", import.meta.url)));

import { assertWithinRpcBudget } from "paseo-plugin-devkit/testing";
await assertWithinRpcBudget(() => handlers.get("doc.render")!(worstCaseInput)); // < 15 s, < 8 MiB

paseo-plugin-devkit/web exports the PaseoWeb Playwright page object for your own browser tests.

Fake agent

Agent-facing plugins (hooks, timeline cards, injected MCP tools) need agent turns to test. ppd daemon up --fake-agent installs fake-agent, a credential-free provider plugin (assets/fake-agent) that runs a scripted turn per prompt. It emits the timeline items real adapters produce, does the file effects for real in the agent's cwd, and calls tools on the MCP servers in its session config (what plugins inject in before("agent.create")), over HTTP or stdio. Paseo's own mock provider needs a development build and supports no MCP servers; this replaces it.

mkdir -p /tmp/ws
npx ppd daemon up --fake-agent
npx ppd paseo -- run --provider fake-agent --cwd /tmp/ws '{"steps":[{"write":{"path":"notes.md","content":"hi"}},{"say":"done"}]}'

paseo run --cwd creates a workspace for that directory, so leave --workspace off daemon up here: with two workspaces, ppd web needs --workspace to know which one to open.

A prompt is a script when it is JSON ({"steps":[...]} or a bare array) or contains a ```fake-agent fenced block. Otherwise the agent reads turn N from <cwd>/.fake-agent.json ({"turns":[script, ...]}, the last one repeats), else echoes the prompt as one assistant message. Steps, one key each, run in order:

| Step | Effect | Timeline item | | --- | --- | --- | | {"say": "text"} | | assistant_message | | {"think": "text"} | | reasoning | | {"write": {"path", "content"}} | writes the file (relative to cwd), creating directories | tool_call Write, detail: {type: "write", filePath} (absolute) | | {"edit": {"path", "old", "new"}} | replaces the first old | tool_call Edit, detail: {type: "edit", filePath, oldString, newString}; failed if the file or string is missing | | {"bash": {"command", "output"?, "exitCode"?, "run"?}} | with run: true, runs sh -c in cwd (60 s) and reports real output; only in a daemon ppd daemon up started (its home has .ppd-home), elsewhere the step fails the turn without running | tool_call Bash, detail: {type: "shell", command, cwd, output, exitCode}; failed if exit code is not 0 | | {"mcp": {"server", "tool", "arguments"?}} | initialize then tools/call on that server ("*": every server; none configured: nothing) | tool_call mcp__<server>__<tool>, detail: {type: "unknown", input, output}; failed on errors or an unknown server | | {"sleep": ms} | waits (an interrupt cancels the turn) | | | {"fail": "message"} | ends the turn as failed | error |

"stepDelayMs": N next to steps pauses before every step. A turn emits user_message, then the steps, then ends completed, failed (a fail step or an invalid script) or canceled, so agent.turn_started and agent.turn_ended fire as with a real provider. Like real adapters, a file a shell command writes is not attributed to it.

From tests (paseo-plugin-devkit):

import { agentTimeline, pluginRows, runFakeAgentTurn, sendFakeAgentTurn } from "paseo-plugin-devkit";

const { agentId, status } = runFakeAgentTurn([{ write: { path: "a.ts", content: "x" } }, { say: "done" }], { cwd: workspace });
sendFakeAgentTurn(agentId, [{ mcp: { server: "my-tools", tool: "show_to_human", arguments: { title: "hi" } } }]);
const cards = pluginRows(agentTimeline(agentId), "turn-summary"); // plugin rows, which `paseo logs` omits

agentTimeline reads the canonical timeline with the Paseo client inside the installed app (it is not on npm), so it needs the desktop app or PASEO_APP. Appended plugin rows live in daemon memory; hooks run asynchronously, so poll briefly after a turn. test/create-e2e.test.ts is a complete example.

Safety model

ppd is built to run next to your real Paseo and next to coding agents.

• Port 6767 is refused everywhere (daemon, android), and so is any home overlapping ~/.paseo or a non-temp PASEO_HOME.
• Dev homes are created under $TMPDIR (os.tmpdir(), a /var/folders/... path on macOS, not /tmp), must sit strictly inside a temp dir and carry a marker file. Only marked homes are ever deleted, including the home of a daemon that died.
• The dev daemon and every Paseo CLI call aimed at it get a scrubbed env: inherited PASEO_* variables (PASEO_HOME, PASEO_AGENT_ID, PASEO_CLI, ...) are dropped (the daemon keeps only PASEO_NODE_ENV), so running ppd inside a Paseo agent cannot reach the parent daemon.
• Every Paseo CLI call aimed at a dev daemon gets --home <dev home> (only paseo --version and paseo plugin init run without it); --host and --home passthrough are rejected.
• daemon down signals a pid only if its command line carries that dev home.
• android never sends input, never presses BACK or HOME and never changes settings. It refuses to guess between several devices.
• release and registry update print commands by default; public actions need a TTY confirmation or --yes.

Safety violations exit with code 3.

Claude Code skill

skills/paseo-plugin-dev teaches an agent the isolated-daemon loop, the hard rules above, the host-contract table, device testing (Android, iOS simulator), registry rules and habits for long runs. Claude Code loads it when you work on a Paseo plugin, for example "verify my plugin on a dev daemon and screenshot the panel".

Install it for all projects:

mkdir -p ~/.claude/skills
cp -R node_modules/paseo-plugin-devkit/skills/paseo-plugin-dev ~/.claude/skills/

Or for one plugin repo: copy the same directory into the repo's .claude/skills/. From a clone of this repo, the source is skills/paseo-plugin-dev.

CI

examples/ci.yml is a drop-in workflow for a plugin repo:

- run: npm ci
- run: npm test
- run: npx ppd check              # APPROXIMATION on Linux runners (no Paseo app); eval, imports, Hermes, sizes
- run: npx ppd registry precheck

It also has a weekly job that checks out Paseo main, sets PASEO_SOURCE and runs ppd check with the latest SDK, so upstream changes break your CI before they break your users. This repo's own CI runs typecheck, tests, a CLI smoke test and a package check on Node 22 and 24, builds the docs site, and runs the test suite weekly against Paseo main.

Compatibility

Verified on macOS with Paseo 0.11.4 (desktop app and CLI). CI runs on Linux without Paseo, where daemon tests skip and ppd check runs as an approximation.

ppd relies on parts of Paseo that are not a public API. When one of them moves in a new Paseo release, ppd says what it expected instead of blaming your plugin:

| Relies on | Used by | When it changes | | --- | --- | --- | | compiler.js, bundle-evaluator.js, manifest.js in Paseo.app/Contents/Resources/app.asar/node_modules/@getpaseo/server/dist/server/server/plugins | ppd check (real compile and server evaluation) | paseo-compile fails with "could not load Paseo's plugin compiler", the expected path, and the verified and found versions. ppd check --approx or PASEO_SOURCE works around it. | | The Lucide exports in the app's web bundle (app-dist/_expo/static/js/web/index-*.js) | icon checks | lucide-icons warns and falls back to the plugin's own lucide-react-native. | | @getpaseo/client and ws inside app.asar | agentTimeline | the call fails naming the modules it looked for. | | paseo daemon run --home, PASEO_HOME, PASEO_LISTEN and the config.json keys | ppd daemon up | a start failure prints the daemon output and how it was started. | | Accessible names in the web UI ("New workspace", "Open menu", "Workspace actions", "Search commands") | ppd web, PaseoWeb | a timeout names the label it waited for. | | Rules vendored from Paseo (client registration, manifest schema, build options) | ppd check without the app | drift shows up in the weekly CI job against Paseo main. |

ppd daemon up prints a note when the installed Paseo is not the verified version; ppd doctor shows the same text as a warning on its paseo CLI line.

Limitations

• Stubbed: client eval and the Hermes smoke run use stub host modules, not the real app. They catch load-time failures, not rendering bugs. Use ppd web and a device for those.
• Without the Paseo app or PASEO_SOURCE (Linux CI) the compile is an approximation and icon names are checked only against the plugin's own lucide-react-native, if any.
• Time limits are 30 s per evaluated bundle and 120 s for the real compile, server evaluation included. There is no CLI flag; runChecks and describeHostContract take evalTimeoutMs and compileTimeoutMs.
• The 32 MiB relay budget comes from field experience, not from Paseo source; direct connections allow 100 MiB.
• ppd web needs Google Chrome or a Playwright Chromium matching playwright-core. Its selectors follow the Paseo 0.11 web UI and may need updates when the app changes.
• No iOS command: the simulator build is manual (see the skill). No multi-touch injection for Android.
• ppd release and ppd registry update are tested against local Git repos and a stub validator, not yet end to end against GitHub and the live registry.
• The daemon end-to-end tests are opt-in (PPD_E2E=1 npm test, PPD_E2E_PORT to pin the port) because CI has no Paseo CLI.
• macOS and Linux only. Tested on macOS with Paseo 0.11.4 (see Compatibility).

Roadmap

Devkit:

• ppd ios for the simulator.
• A fake-host harness for RPC integration tests.
• A provider template for ppd create.

Most remaining pain needs Paseo changes. Upstream asks:

• An abort signal for plugin RPC handlers on timeout or disconnect.
• Respawn of crashed plugin children (with backoff).
• A safe-area insets export in the plugin client SDK.
• Registration of plugin horizontal scroll views so swipes do not open the sidebar.
• A previewer hook for the Files tree.
• Prebuilt iOS simulator builds of the app.

Contributing

See CONTRIBUTING.md. Short version: npm ci && npm run typecheck && npm test, one focused change per PR, and nothing may ever touch port 6767 or ~/.paseo.

License

MIT. Some files adapt code from Paseo (Apache-2.0, Copyright (c) 2025-present Mohamed Boudra); those portions stay under Apache-2.0. Each such file starts with a notice, and THIRD_PARTY_NOTICES lists them with the full license text.