Package Stack

Feynman is built on stock Pi and uses curated Pi packages for its capabilities. Feynman itself is a Pi package: its package.json pi manifest declares its extension, prompts, skills, theme, and subagent definitions. Feynman launches Pi with PI_CODING_AGENT_DIR=~/.feynman/agent and lists itself and its core packages in ~/.feynman/agent/settings.json as local-path packages, so subagents load the same tools as the main session.

See Pi’s upstream docs for packages, extensions, and skills.

Core packages

These are npm dependencies of Feynman, installed with it and loaded unmodified from its install directory.

Package	Purpose
pi-subagents	The subagent tool, /subagents, and /run; powers delegated and parallel research runs
pi-web-access	web_search, source_check, fetch_content, and get_search_content for web search and page, PDF, and GitHub retrieval
pi-docparser	document_parse, document_search, and document_screenshot for local PDFs, Office documents, spreadsheets, and images
pi-btw	/btw side conversations while the main research agent is busy
@companion-ai/alpha-hub	alphaXiv client library behind Feynman’s alpha_* tools and feynman alpha

They update when you upgrade Feynman. You do not need to install them individually.

Bundled research extension

Feynman’s own extension registers these tools and commands:

Group	Contents
AlphaXiv tools	alpha_search, alpha_get_paper, alpha_ask_paper, alpha_read_code, alpha_annotate_paper, alpha_list_annotations
Science database search	feynman_science_database_search over Semantic Scholar, OpenAlex, arXiv IDs, PubMed, Europe PMC, bioRxiv/medRxiv, and Crossref
Hugging Face Hub tools	hf_dataset_info, hf_repo_files, hf_repo_read_file
Commands	/help, /init, /outputs, /tools, /service-tier

Optional packages

Install on demand with feynman packages install <preset>.

Package	Preset	Purpose
@samfp/pi-memory	memory	Preference and correction memory across sessions
@luxusai/pi-hindsight	hindsight	Hindsight-backed long-term memory. Requires a Hindsight server or Hindsight Cloud account

To search past Feynman sessions without a package, search the session files directly:

rg -n "protein folding" ~/.feynman/sessions

Installing and managing packages

List core packages and optional presets:

feynman packages list

Install a specific optional preset:

feynman packages install memory

Updating packages

Update the optional packages you installed, through Pi’s own pi update --extensions:

feynman update

Update one package, by preset name or Pi package source:

feynman update memory

Core packages are not touched by feynman update because they ship with Feynman; to update them, upgrade Feynman itself (rerun the installer from the Installation guide, or npm install -g @companion-ai/feynman@latest).

Runtime versions

Feynman 0.5.25 runs Pi 1.0.2 with pi-subagents 0.76.0, pi-web-access 0.35.0, pi-docparser 4.0.0, pi-btw 0.7.1, and Alpha Hub 0.1.6 as ordinary npm dependencies, and does not modify any of them on disk. Every release is checked by booting the installed CLI in Pi RPC mode on Linux, macOS, and Windows.