Feynman: the open workbench, read closely

This is one part of a series on research-agent systems. The landscape piece states where the field stands and sets all twenty-seven systems side by side: Agentic science harnesses: the landscape.

Feynman deep-dive

Full dossier from research card t_cdfcffb6. What it is, who builds it, how it works, its literature-review capacity, how it was received, and how it compares. Feynman gets the deep treatment because it is the newest, fastest-growing open-source harness in the set, and the one most shaped by its reception.

What it is

An open-source AI research agent (CLI; the early science workbench via feynman serve was retired in the v0.4.0 "deslop", 23 Sep 2026) built on a stock Pi agent runtime, with alphaXiv plus OpenAlex / Semantic Scholar / PubMed / Europe PMC / bioRxiv / Crossref for paper search and analysis. Bundled agents: Researcher (evidence gathering, numbered Sources), Reviewer (severity-graded FATAL/MAJOR/MINOR), Writer (structured drafts from evidence only) and Verifier (citation and URL verification, dead-link removal; runs last). Ten research workflows including /deepresearch, /lit (literature review with consensus, disagreements and open questions), /audit (paper claims vs public codebase), /replicate, /recipe, /review, /compare, /draft, /autoresearch and /summarize. One-line install (curl feynman.is/install), standalone bundle with pinned Node runtime, SHA-256 verified. Supports hosted providers (Anthropic, OpenAI, Google, OpenRouter, GitHub Copilot, Bedrock) and local models (LM Studio, LiteLLM, Ollama, vLLM).

GitHub stars

10,094

Forks

1,108

Open issues

0

Created

19 Mar 2026

Last commit

31 Oct 2026

License

MIT

Language

TypeScript

Latest release

v0.5.61 · 30 Oct

Team & origin

• Owner: founded under the Companion-Inc GitHub org ("Companion", "Personal AI", US, created 2025-09-11); the repo sat briefly under the founder's personal account in early September, and as of the 28 Sep 2026 check github.com/advaitpaliwal/feynman still redirects to github.com/Companion-Inc/feynman (API verified), with the v0.3.49 re-launch release confirming the org as home
• Founder / sole maintainer: Advait Paliwal (@advaitpaliwal): 470 of 478 commits; founded YouLearn (AI tutor, 2M+ users), co-founded Friday (YC-backed), MIT Augmentation Lab; based San Francisco
• Company: single founder-led entity; getcompanion-ai org 404s (renamed to companion-inc); org vs personal hosting has settled back under the company, re-verified 28 Sep 2026 when the release wave landed from the org repo
• Funding: no public round verified (unverified), Tracxn lists a "Companion Ai" profile with no funding raised (entity match unverified); the "$2.5M seed" snippet refers to a different Companion Labs
• Sibling product: companion.ai: personal AI assistant (Gmail/Calendar/Notion/Slack/Linear, freemium)

Architecture

• Runtime: Pi 1.0.0 since v0.5.24 (3 Oct 2026), now on Pi 1.1.0 as of v0.5.30 (7 Oct; adds Claude Haiku 5.5 and browser-login/retry fixes): fullscreen terminal UI by default (feynman --tui-mode regular to opt out), clean npm audit since v0.5.25; capabilities ship as Pi packages and skills; alphaXiv plus literature databases for paper search/analysis
• Bundled agents: Researcher (evidence gathering, numbered Sources), Writer (structured drafts from evidence only), Reviewer (severity-graded FATAL/MAJOR/MINOR), Verifier (anchors claims to sources, verifies URLs live, removes unsourced claims, runs last); workflow prompts call them via the subagent tool when delegation helps
• Compute: Docker (isolated containers), Modal (burst GPU), RunPod (persistent GPU pods)
• Workspace contract: slug-based file naming, outputs/.plans/, CHANGELOG.md lab notebook, provenance sidecars enforced for /lit
• MCP servers: feynman mcp add|list|remove manages MCP servers from Feynman's own settings (v0.5.61, 30 Oct 2026), saved to ~/.feynman/agent/mcp.json and loaded by every session
• Install: one-line installer (curl feynman.is/install), npm install -g @companion-ai/feynman, or skills-only install into Codex/Claude/OpenCode

Reception: positive

• PRO Distinctive paper-vs-codebase audit workflow (feynman audit <arxiv-id>): automates checking whether code actually does what the paper claims (r/LocalLLaMA; Medium Open Intelligence review)
• PRO Dedicated Verifier agent catches hallucinated citations and kills dead links: "this one has an entire agent dedicated to catching that before it reaches you" (r/LocalLLaMA)
• PRO "For research it is way better than Perplexity even though it's still not perfect" (r/LocalLLaMA, pippes23)
• PRO Described as "Claude Code for scientific research" (LinkedIn, Jacob Minz: snippet only, page not fully scraped)
• PRO Forked for public health / HPSR by daktre: "it's become a working tool" (notes.daktre.com, built at IPH Bengaluru)
• PRO Roundtable (@RoundtableSpace) X post: "does in seconds what takes academic professionals hours... One download. Zero cloud. Fully free.", 324 likes, 43 retweets (2026-04-12)
• PRO ~10k stars in under seven months from creation (10,094 at the 9 Nov check); sustained cadence: 69 releases since 23 Sep (v0.3.49→v0.5.66; 166 releases to date), including the Pi 1.0/1.1/1.3 runtime moves, rate-limit hardening, first-run onboarding and a week of token-cost work in pi-subagents 0.79.x
• PRO Package traffic: 51,133 npm downloads in the last month on the registry API (28 Sep to 27 Oct 2026, @companion-ai/feynman), with about 12.6K in the most recent week. The earlier package-page reading of about 119.5K a month is not reproduced by the API and is marked unverified
• PRO Deliberate refocus: the v0.4.0 "deslop" removed the workbench, biomedical modelling templates, PaperRank and other scope outside the research loop, keeping find papers → read → synthesise with verified citations → audit vs code → replication planning (release notes; removed code preserved at the archive/pre-deslod-0.3.49 tag)
• PRO /lit eval on GPT-5.6 Terra: 4 of 4 questions completed, all 44 citations resolved with matching titles, each under 11 minutes (v0.5.3 notes; 0.5.2 runs were 9-14 minutes)

Reception: negative / caution

• CON /lit had flaws at 0.3.x (model-recognition problems; Mac setup friction: r/LocalLLaMA, pippes23); the 0.5.x line addressed the Crossref / Semantic Scholar failure modes, though independent validation of the fixes is still thin
• CON The 0.4.0 deslop narrowed scope decisively: the workbench, biomedical modelling templates and PaperRank were removed (recoverable at the archive/pre-deslod-0.3.49 tag) and arXiv free-text topic search was dropped in favour of ID lookup: search topics via Semantic Scholar or OpenAlex; the daktre-era "no native PubMed" gap is closed (PubMed and Europe PMC are in the source set), but the tool remains literature-first
• CON Known issue (v0.5.3 notes): Claude Opus 5.5 refuses some biology literature reviews ("The model refused to complete the request", e.g. /lit on CRISPR base editing); the same topics run on GPT-5.6 Terra
• CON "Still early; best suited to technical users comfortable with CLI-style workflows" (Gatsbi blog, 13 Jun 2026)
• CON Seen as over-optimised for paper writing by a social-science blogger (Jared Knowles, 4 Jun 2026)
• CON Low HN footprint: launch story got 3 points and one joke comment ("Needs a bongo player agent and a /riff workflow") (HN, 7 Apr 2026)

Reception: neutral observations

• NEU "Nobody is talking about it" framing despite 2.3k stars at the time: awareness lags star count (r/LocalLLaMA)
• NEU Positioned as a local-first, self-hostable alternative to hosted research tools (Gatsbi blog)
• NEU Listed among science AI agents in danmackinlay.name notebook: "ships as either a full agentic loop or as a bundle of skills"
• NEU Explicitly NOT a substitute for protocol-driven systematic reviews: needs Embase / Web of Science / Covidence / Rayyan for those (daktre fork notes)
• NEU Name collision: @feynmanai on X is a different product (Feynman technique study app); an Obsidian plugin is a different project: verify by URL before citing

X / GitHub / docs presence

• X account: none verified (unverified): no dedicated Feynman or Companion product handle found. Founder @advaitpaliwal announced Companion from a personal account
• GitHub: 10,094 stars, MIT, TypeScript, 1,107 forks, 0 open issues; last commit 8 Nov 2026; releases continued through 8 Nov (v0.5.62 to v0.5.66; 166 to date); repo description changed to "The open source AI research agent" in v0.5.35; homepage feynman.is. Repo URL: github.com/Companion-Inc/feynman is canonical: advaitpaliwal/feynman 301-redirects there (API verified 12 Oct 2026).
• Docs: feynman.is/docs (verified live): installation, setup wizard, workbench, CLI + slash command reference, release notes; mirror at getcompanion-ai-feynman.mintlify.app
• Release cadence: quiet after v0.3.48 (6 Sep); development resumed 23 Sep and has not paused: fifteen releases in the first six days (v0.3.49→v0.5.12), fourteen more to 5 Oct (v0.5.13→v0.5.26), then ten more to 12 Oct (v0.5.27→v0.5.36; highlights: Pi 1.0.3/1.0.4/1.1.0, Claude Haiku 5.5 support, the pi-subagents 0.77.0 subagent-token cut, PubMed affiliation and italics fixes, OpenAlex recovery hints, and first-run onboarding; latest v0.5.36, 12 Oct; 136 releases to date)

Literature-review capacity (detailed)

How it searches

alphaXiv via alpha CLI: paper search, Q&A, code reading, annotations. Web search with three routing modes: auto (Perplexity if key configured, else Gemini), perplexity (force Sonar), gemini (zero-config grounding via signed-in Chromium, default), with 2 to 4 simultaneous varied-angle queries, domain filtering, recency filtering, full-content retrieval. Literature sources after the 0.4.0 deslop: OpenAlex (incl. semantic: embedding search and free-key guidance), Semantic Scholar (bulk citation-sorted, plus relevance / pub-date sorts), arXiv (ID lookup only), PubMed, Europe PMC (incl. open-access full-text sections), bioRxiv/medRxiv, Crossref, plus fetch_content for direct retrieval. The biomedical "Feynman Bio Tools" connector set (ClinicalTrials.gov, FDA, ChEMBL, genomics, structures and more) was removed in the deslop. Past sessions are searched with grep/rg over ~/.feynman/sessions (the session-search preset was removed in 0.5.4).

How it synthesises

/lit: 6 stages: Plan (scope, source types, task ledger; waits for confirmation), Gather (researcher subagent, tasks marked done/blocked/superseded), Synthesize (consensus / disagreements / open questions; strong claims swept against a verification log and downgraded if inferred or single-source), Cite (verifier adds inline citations), Verify (reviewer checks unsupported claims, gaps, zombie sections; FATAL fixed before delivery, MAJOR → Open Questions, MINOR accepted), Deliver (outputs/<slug>.md + provenance sidecar). /deepresearch runs parallel researchers with synthesis and verification pass; workflows now wait for background subagents before the final answer. The old /rank PaperRank workflow was removed in 0.4.0 (its "what to read first" role moves into /lit and /deepresearch). Lab/PI corpus mode maps publication trajectories. /compare builds side-by-side agreement/conflict matrices. /summarize keeps long sources on disk instead of in context.

Citation handling

Source-grounded outputs: every claim links to papers, docs or repos with direct URLs. The Verifier agent anchors every factual claim with [1]..[N] inline citations (multiple sources [7, 12] supported), verifies each URL is live via fetch, substitutes archived/mirror alternatives for dead links, removes dead-link-dependent and unsourced claims, builds the final numbered Sources with no orphans; "verify meaning, not just topic overlap"; refuses fake certainty ("verified/confirmed/reproduced" only with underlying evidence). /lit provenance record: date, sources consulted vs accepted vs rejected, verification status, intermediate files. Full-text access resolution runs through the literature tools (OpenAlex, arXiv, alphaXiv, DOI lookup, Europe PMC); the retired /paper shortcut is noted in the release history.

Limitations

Literature-first by design: the source set is OpenAlex, Semantic Scholar, arXiv, PubMed, Europe PMC, bioRxiv/medRxiv, Crossref and web search; the workbench, biomedical modelling connectors and PaperRank were removed in 0.4.0 (recoverable at the archive/pre-deslod-0.3.49 tag). Known issue: Claude Opus 5.5 refuses some biology literature reviews (v0.5.3 notes); the same topics run on GPT-5.6 Terra. Not a substitute for formal systematic review methodology: no native PRISMA / Embase / Web of Science support. Premium model tiers are never auto-picked (available via --model / /model). Local models need a larger context window configured (setup docs). Thinking levels: --thinking off|minimal|low|medium|high|xhigh.

Pricing / hosting / provider tie

Free, open-source, MIT license: no SaaS subscription. Cost to run: user pays only their connected LLM API costs. Providers: Anthropic, OpenAI, Google, OpenRouter, GitHub Copilot (OAuth), Amazon Bedrock (AWS credential chain); local via LM Studio, LiteLLM Proxy, Ollama/vLLM (baseUrl + API key). Optional packages: memory, hindsight (needs a Hindsight server/cloud); the session-search preset was removed in 0.5.4.

Comparisons to other harnesses

vs GPT Researcher

: GPT Researcher for flexible deep-web cited reports (planner + execution agents); Feynman for local-first paper reading, auditing and drafting. Feynman rated "moderate" experiment support vs GPT Researcher "limited" (Gatsbi)

vs Stanford STORM

: STORM is Wikipedia-style knowledge curation (outline-first); Feynman is a local workflow with paper/code audit and citation-oriented outputs. STORM is not designed for experiments or academic manuscripts (Gatsbi)

vs Agent Laboratory / AI-Researcher / Arbor

: those are closer to full autonomous researchers (end-to-end AI/ML research workflow); Feynman is distinguished by local-first operation, audit and citation verification (Gatsbi)

vs MiroFlow

: MiroFlow is a benchmark-oriented high-performance agent framework (FutureX/GAIA/HLE/xBench-DeepSearch); Feynman is a workflow-oriented local research assistant (Gatsbi)

vs Perplexity

: "for research it is way better than Perplexity even though it's still not perfect" (r/LocalLLaMA, pippes23)

vs Claude Code

: described as acting like "Claude Code for scientific research" (LinkedIn, Jacob Minz; snippet only)

vs Elicit

: weak signal: a Facebook group OCR roundup lists Elicit alongside Feynman in open-source research tools (incomplete OCR; treat as weak)

vs Covidence / Rayyan

: Feynman's own community notes it will not replace protocol-driven systematic reviews; those still need Embase, Web of Science, Covidence and Rayyan. Feynman is for rapid reviews, scoping preliminaries and grant backgrounds (daktre fork notes)