Package Stack
Feynman is built on the Pi runtime and uses curated Pi packages for its capabilities. Packages are managed through feynman packages commands and configured in ~/.feynman/settings.json.
Feynman also ships a local research extension that registers project-specific tools such as AlphaXiv wrappers, Feynman commands, and read-only Hugging Face Hub inspection. Those extension tools are bundled with Feynman itself rather than installed as separate Pi packages. Pi runtime observability is provided by the bundled pi-otel package, pointed at PostHog AI Observability through trace-specific OTLP variables, and configured for metadata-only spans by default. CLI spans use PostHog distributed tracing and are queryable from posthog.trace_spans; Pi LLM/tool spans appear in AI Observability and as $ai_* events.
This page follows Pi’s upstream docs for packages, extensions, and skills. Feynman adds its own package presets and bundled research extension on top of that model.
Core packages
These are installed by default with every Feynman installation. They provide the foundation for research workflows while still letting Pi own the underlying runtime, RPC transport, provider model, and package loader.
| Package | Purpose |
|---|---|
@companion-ai/alpha-hub | Direct alphaXiv tools for paper and author workflows |
pi-subagents | Parallel agent spawning for literature gathering and task decomposition. Powers the multi-agent workflows |
pi-docparser | Parse PDFs, Office documents, spreadsheets, and images for content extraction |
pi-web-access | Web browsing, GitHub access, PDF fetching, and media retrieval |
pi-otel | OpenTelemetry spans for Pi sessions, model calls, turns, and tool usage, exported without prompt or tool payload content |
These packages are updated together when you run feynman update. You do not need to install them individually.
Bundled research extension
| Tool group | Purpose |
|---|---|
| AlphaXiv tools | Search papers, fetch paper reports, ask paper questions, read linked code, and manage annotations |
| Hugging Face Hub tools | Inspect dataset metadata, features, splits, access status, and small files from model, dataset, and Space repos |
| Feynman commands | /help, /outputs, /init, /feynman-model, /service-tier, and discovery helpers |
Optional packages
Install on demand with feynman packages install <preset>. These extend Feynman with capabilities that not every user needs.
| Package | Preset | Purpose |
|---|---|---|
@samfp/pi-memory | memory | Pi-managed preference and correction memory for research-session continuity |
@luxusai/pi-hindsight | hindsight | Hindsight-backed research-continuity memory. Requires a Hindsight server or Hindsight Cloud account |
@kaiserlich-dev/pi-session-search | session-search | Indexed recall for prior research-session transcripts. Available through Node.js 22.x while its sqlite dependency is native-bound |
Installing and managing packages
List supported optional research packages and their install status:
feynman packages list
Install a specific optional preset:
feynman packages install session-search
Updating packages
Update all installed packages to their latest versions:
feynman update
Update a specific package:
feynman update pi-subagents
Running feynman update without arguments updates everything. Pass a specific package name to update just that one. Updates are safe and preserve your configuration.
This command updates Pi packages inside Feynman’s environment. To upgrade the standalone Feynman app itself, rerun the installer from the Installation guide.