proofpath

Don't guess. Show the evidence.

proofpath checks whether the sources behind a claim actually say what the claim says. Point it at a paper or a draft and it verifies every citation on three levels, then shows you the passage behind each verdict.

1. Does the source exist? — Crossref, Semantic Scholar, arXiv, Open Library, OpenAlex.
2. Is it still valid? — Crossref's Retraction Watch data, and OpenAlex.
3. Does it support the claim? — retrieval and entailment against the source text, with a numeric rule that runs before the model.

Most tools stop at step 1. Step 3 is the point.

Runs locally and free: no API key, no Docker, no server. Windows, Linux, macOS.

uv tool install proofpath
proofpath

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    ⢠⣿⣿⣿⣿⣿⡇       proofpath v0.4.3                                      academic · online · coreml
   ⢠⣿⣿⣿⣿⣿⡟        paste a file path, a URL, or a claim.                      /help  /config  /quit
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The bird is a raven — the same one as on the website — drawn in Braille cells in the rich theme and in ASCII in plain.

Bare proofpath opens the terminal UI (a recorded session in both themes, with SVG screenshots of a real run in rich and plain). Each run is one panel in its own accent: the command on the top border and the run's state at its right, a fixed-column stage table underneath (✓ finished, ⏺ still running or finished with something unverified, a real progress bar on the active stage, the provider that produced each number at the right), a rule, then the findings — location, reference, the state word as a badge, the tier — with the finding's notes and the claim (you) and the passage (source) it was checked against under it. The bottom border carries the run's coverage; the docked footer draws it as a bar and never scrolls away.

Paste a path and it runs; every one-shot verb is a slash command (/check, /resolve, /fetch, /config, /cache), runs can be started while others are in flight and stopped with /cancel #n — a stopped run keeps what it had decided. Click (or press enter on) a finding to read the whole quoted passage; ⧉ copies it; a finding's reference is a link to its source. When a publisher blocks the plain fetch, the permission question is asked inline, under the stage that hit the wall, with [allow once] [always] [no] [never] — or, from the bar, /allow once, /allow always, /allow no, /allow never.

Windows / NO_COLOR. The look above is the rich theme, chosen when the terminal gives evidence of truecolor (COLORTERM, Windows Terminal, iTerm2, kitty, WezTerm, Ghostty, VS Code, Terminal.app). Under NO_COLOR, --no-color, -q, TERM=dumb, legacy conhost or a CJK locale the plain theme draws the same runs as flat ASCII rows in the terminal's own 16 colours — the state words, the coverage and every honesty sentence are identical, only the drawing changes. PROOFPATH_THEME=rich|plain forces either, for screenshots and bug reports.

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    _/ /
   /  /       proofpath v0.4.3                                          academic . online . coreml
  /__/        paste a file path, a URL, or a claim.                          /help  /config  /quit
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The same engine behind a pipe or in CI:

proofpath check paper.pdf                       # report → report.md, exit 0/1/2
proofpath check draft.md --format json | jq '.coverage'
proofpath check draft.md --format sarif --out draft.sarif   # any SARIF 2.1.0 viewer (VS Code's SARIF Viewer, …)
proofpath -q check - < draft.md                 # stdin; findings and coverage only

--format sarif writes a SARIF 2.1.0 log: one result per finding on its line, the quoted passage in the message, the exact honesty state in properties, and the run's coverage in the run's properties, so a log opened without the terminal still says how much was read. Exit codes are the interface: 0 clean, 1 findings (every UNVERIFIED and LOW CONFIDENCE counts), 2 the run itself failed — no text parsing needed to gate a job. Piped or in CI there is no prompt: an ask permission is treated as deny and reported.

The install carries no browser engine. When a publisher blocks the plain fetch, proofpath asks once before downloading one — about 280 MB, into its own environment and the shared browser cache, never system-wide — and remembers the answer. proofpath config set permissions.install_browser never stops it asking at all.

Honesty

Most verdicts are "not enough information", and that is the honest answer. On SciFact dev only 135 of 340 claim–source pairs score above the decision threshold at all; the other 60 % are NEI rather than guessed. Full text is openly reachable for well under half of published citations, so a real document loses more on top.

Every report states its own coverage (and adds a warning line when it is thin):

7 refs: 1 ghost, 2 unsupported, 4 ok
fulltext   72%
abstract   14%
unverified 14%

When a quarter or more of the sources could not be read, a further line says so: coverage is weak: unread sources may hold more, so this is a lower bound. When the browser step was not permitted, a line counts the sources it cost: skipped N source(s) because the browser was not permitted — proofpath config set permissions.install_browser ask.

No verdict without its passage. SUPPORTED and REFUTED cannot exist without the quoted sentence they rest on — the cache schema itself refuses to store one.

The confidence tiers are measured, not chosen — read off a sweep on SciFact dev (details): decide = 0.45, medium = 0.457948, high = 0.99933. Two caveats belong next to those numbers. high was fitted on the same split it is reported on: an in-sample point estimate over 21 verdicts (at least 18 correct — roughly 0.65–0.95 at 95 % confidence), so read it as "the model was near-certain here", not as a guarantee of 85 % precision. And medium lands almost exactly on decide, so low is practically empty among asserted verdicts — the display is effectively two tiers: near-certain, and asserted at all.

Citations it reads

Numeric markers — [12], [12,15], [12-15], Nature-style superscripts — and, since v0.2, author-year: (Smith et al., 2020), Smith (2020), (Smith, 2020; Jones, 2019), 2020a/2020b collisions, ibid. and op. cit., and a mixed (Smith, 2020; [12]). Pairing rate on the hand-built author-year set: 0.940 (83 expectations over 55 passages, details); the numeric set is at 108 of 109. Still unpaired, and reported rather than guessed: a surname that is not the entry's first author, a year off by one, two surnames sharing a last word (Berg / van der Berg), Smith 2020 with no comma, and an initialism such as (WHO, 2020) against "World Health Organization". A marker no entry matches is listed as an unresolved marker.

What the states mean

Absence of evidence is never reported as evidence of absence. Each of these is a distinct, printed state (spec §15), never collapsed into a verdict:

An earlier build sometimes aborted with 134 after printing a complete report (ONNX runtime teardown); fixed in v0.1 — 20 of 20 piped runs exit 1 (live runs).

Known limitations

• Superscript citations only when the PDF marks them as superscript; a PDF that draws them as ordinary digits loses them, and km² can be read as [2].
• Abstract fallback: when only an abstract is reachable the verdict is labelled LOW CONFIDENCE (abstract only). Three sentences is not a source.
• An unnumbered two-column bibliography is cut at line breaks (RoBERTa's ACL list: 103 entries for ~50, half of them with no author), so author-year pairing over such a list resolves few items — 15 claims where a rejoined list would give 65. The largest open item for author-year pairing.
• A reference list without a References heading is read by its shape in paged formats — the last contiguous run of numbered paragraphs — which recovers only that last block (AlphaFold: 17 of 84 entries) and drops the prose printed before a block's first entry.
• The 0 % false-ghost rate is measured on 274 hand-built references, and rule 3 is paid for in recall: a fabricated First Last and First Last. Title. Venue. with no year between the names and the title is reported as not in bibliographic indexes, not as a ghost, and a proceedings-volume record can accept a fabricated paper cited into that volume as RESOLVED (low confidence) — the set's one fabricated acceptance (0.9 %) (details).
• A cold run of a long bibliography is still serial through the providers (129 references: minutes). Only the TUI runs several documents' network stages at once.
• A refused or failed browser install is reported, not hidden: the source is UNVERIFIED (blocked, browser not permitted) with the install log, never silently counted as unreachable.
• Coverage is not perfectly reproducible: two runs minutes apart can read a different number of sources, depending on which providers answered.
• The judge is a second opinion, not a second verdict. --judge asks the model only about the low-tier verdicts (1 of 10 on the live draft), and its answer is printed beside the local verdict, never in place of it. --summarize is one extra call over the finished report, labelled model-written; if the provider does not answer, the markdown report, the JSON and the terminal say so (judge status / summary status in the header). The SARIF log does not carry it — it is a findings document.

Speed

Apple Silicon Mac, models already downloaded:

The first ever run also downloads about 250 MB of ONNX models. Since v0.2 a cached re-run asks the network for nothing: reference resolution and the retraction check are cached (resolutions 30 days; a retraction hit 30 days, a miss 7 days), the fetched text for 7 days, and chunks and verdicts for as long as the text is unchanged. The models are still loaded, and any source whose text has expired or was never read is fetched again — the PDF re-run above (v0.1) still spent 22 s fetching and re-scored 3 of 102 claims.

Looking inside the cache

Everything proofpath fetches, embeds and decides lands in one plain SQLite file:

proofpath cache            # where it is, what it holds, how many lookups it remembers
proofpath cache ls         # sources, chunk/verdict counts, text expiry
proofpath cache show <id>  # one source's chunks and verdicts
proofpath cache clear --expired

Open proofpath cache path in DB Browser for SQLite, TablePlus or DBeaver — plain tables, no extension. Raw publisher text expires after 7 days; verdicts keep the passage they quote; a provider outage is never stored. proofpath resolve REF and proofpath fetch URL|DOI run either half on its own.

Posts and the links inside them (v0.4)

A social post is not a source. What proofpath checks is whether the links inside it back what it says:

proofpath check --url https://bsky.app/profile/bsky.app/post/3movpwtbjgs2d
proofpath check --url https://news.ycombinator.com/item?id=8863
proofpath check -                 # paste the text of a post that cannot be read

A page is not a post: paste the claim as text with the address inside it, and the page is fetched as that claim's source.

Every sentence of the post is checked against the pages its links point to, and the post's own words are never allowed to stand as their own evidence.

The Reddit path is built against Reddit's documented shapes and covered by fixtures, but it has never run against Reddit on this machine — nobody here has an app to register. Bluesky, Hacker News and Mastodon were each read live before release.

Optional LLM judge (v0.3)

Everything above runs locally, and the default run makes zero LLM calls. Two flags add an LLM at the end, and only there:

proofpath check paper.pdf --judge        # a second opinion on the low-confidence verdicts
proofpath check paper.pdf --summarize    # one model-written paragraph over the finished report
proofpath config check                   # proves the key works before you spend a run on it

What --judge does. After the local verdicts are final, the verdicts the models were least sure about — the low tier, never a numeric mismatch and never a claim without a quoted passage — go to the model in batches of up to 20 (about 7k tokens), each with its claim and the passage it was checked against. The model answers from the passage alone, and its label and one-sentence rationale are printed beside the local verdict: = judge (groq openai/gpt-oss-120b): NEI — …. The local verdict, the finding kind and the report's states never change. Opinions are cached with the verdict, so a re-run asks nothing.

What it cannot do. It never sees a source document, so it cannot introduce a claim or an evidence passage of its own; it cannot turn NEI into SUPPORTED; it cannot hide a source that could not be read. If the provider is down, rate-limited or the key is wrong, the run finishes on the local verdicts and says so in the stage line, the report header (judge status:) and the JSON — -q cannot hide it.

What --summarize does. One final call turns the finished markdown report into 3–5 plain sentences a reader can act on. It runs after the report is complete, its only input is that report, it is off by default in the CLI and the TUI (/summarize there), and the output is labelled (model-written, <provider> <model>). --summarize alone is exactly one call; with --judge the escalation runs first.

Cost. The footer counts the calls and the stage line the tokens: Judging … 1 of 10 verdicts reviewed, 1 call, 613 prompt · 193 completion tokens and Summarising … 98 words, 1 call, 1,608 prompt · 343 completion tokens on the live draft (details). Groq's free tier allows roughly one call a minute. Only the low-tier verdicts are sent — 1 of 10 on that draft — and up to 20 go in one call, so a long bibliography costs a handful of calls, not one per citation.

Providers. Default is Groq openai/gpt-oss-120b (free without a card, no training on submitted data). proofpath config set judge.provider gemini switches to Gemini — note that Google trains on free-tier prompts outside the EEA/UK/CH, and proofpath prints that warning once per run. judge.provider ollama runs fully offline. Gemini and Ollama are fixture-tested and were not exercised live in v0.3.0. All three speak the OpenAI chat/completions shape. The key comes from GROQ_API_KEY / GEMINI_API_KEY in the environment or a .env file, never from config, and is never printed.

Measured

The AVeriTeC row is the one to read before trusting this tool on a news claim. A third of those claims had no readable source at all: 32 of the source URLs needed the browser step, 29 were unreachable, 14 were refused by robots.txt. On the claims that did have a readable source the score is 0.361 — still below the baseline, and every one of the 19 Supported claims was missed. The retrieval and entailment models were calibrated on scientific abstracts, and a fact-check page is a different object: long, discursive, and usually quoting the claim it debunks. Nothing was tuned after that measurement, and no blocked URL was dropped from it.

What proofpath is good at is the academic path the other rows measure: finding out whether a cited paper exists, whether it was retracted, and whether its text says what the sentence citing it claims. Pointed at a news claim on the open web, it is currently a coverage report with a weak verdict attached.

Published SciFact results sit around 70–75 F1, not 95. Nothing is tuned on a test split, and no number is quoted without the run that produced it.

• Design specification — what it does and the measurements behind each decision
• Open items — what is unresolved, and what has not been verified yet · Changelog

The website

The landing page lives in site/ — a static Astro site with no framework runtime. It replays a real /check run, walks the three questions and the six rules, and credits every engraving it uses (Doré's plates for The Raven and Bracquemond's Le Corbeau, all public domain).

cd site
npm install
npm run dev          # http://localhost:4321
npm run build        # dist/
npm run images       # regenerate the halftones from images.manifest.json (committed)

Design decisions and the image pipeline are described in docs/superpowers/specs/2026-09-16-landing-page-design.md.

License

MIT