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Evidence for your next connection.

Independent measurements of remote MCP servers. Every observation has a timestamp.

Read-only probes

MCP server · Knowledge & memory

FactStamp

Verify a company, figure or citation before you rely on it. Card or crypto; signed receipt.

Checks passed
14 / 22

1 failed · 7 not measured

Median response
617 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
18

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Responded

The server completed its last measured handshake. This is an observation, not a guarantee.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
103
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
400
Publisher identityCan the publisher be traced to its source?
312

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 609 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-06-18, serverInfo.name FactStamp.

  • Pass
    Lists tools

    tools/list returned 18 tools.

  • Pass
    Current protocol

    Negotiated 2025-06-18. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 617 ms over 2 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 624 ms over 2 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    2 of 2 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Pass
    Stable tool list

    No tool was removed and no required parameter was added in the last 30 days.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Pass
    Parameters documented

    32 of 32 parameters have a description (100%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Fail
    Website matches publisher

    The website host does not match the reverse-domain namespace.

  • Pass
    Source repo linked

    A repository URL is on file.

  • Not measured
    Repo owner matches

    This namespace is not an io.github login, so the owner comparison does not apply.

  • Pass
    Recently updated

    Updated 2026-10-28T15:44:54.774853Z, within 180 days.

  • Not measured
    Open-source licence

    The GitHub licence lookup has not returned an OSI result yet.

Start using FactStamp

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

claude mcp add --transport http factstamp https://agents.factstamp.dev/mcp

Capabilities

Tools 18

audit_claims

Audit what an agent believes about companies. Send up to 10 claims ({subject:{identifier|name|jurisdiction}, field, value}) and get, claim by claim: supported (the register says this), contradicted (it says something else, shown), stale (the register records it as FORMER, with the date it changed) or not_checkable (we could not check it, and why). Every verdict carries the register's own date and a citation, and the whole batch gets ONE receipt. field is a name from the published vocabulary (legal_name, previous_name, identifier, status, legal_form, registration_date, dissolution_date, registered_address, activity_code), never open text: a field outside it is not_checkable, not a guess. US$0.20 on this rail for up to 10 claims; longer audits go to POST /audit, which prices the body at US$0.02 a claim with a US$0.20 floor. Comes with an Ed25519-signed receipt covering the question, the verdict, the sources and the time, checkable offline against the published key at /.well-known/factstamp-issuer.json — so the check itself can be audited later by someone who was not here.

Discovered
buy_card_package

Included. Opens a Stripe Checkout Session for one card package and returns its payment link and its session id. This tool charges nothing and produces no artefact: on the card rail the thing that taps is a human. The package's work runs only at its redeem path, after Stripe's own record says that session is paid.

Discovered
check_document

A whole document in one call: the claims that can be verified against a primary source, each answered by the door that owns it with its own signed receipt, plus one receipt over the document. Extraction is mechanical, so the claim list and the count are reproducible from your document alone — nothing is inferred. This rail answers the first 5 claims for a flat US$0.25 (5 cents a claim); a better-funded document goes to the pack-funded HTTP door (POST /document, up to 25 claims at the same 5 cents a claim), whose included preview lists the claims and the price before anything is charged — use it first if you are unsure the document holds anything checkable. This door reads PROSE: to check a bare list of references or package versions, use verify_bulk, and a single claim belongs to check_figure, check_entity, verify_citation or verify_package. Comes with an Ed25519-signed receipt covering the question, the verdict, the sources and the time, checkable offline against the published key at /.well-known/factstamp-issuer.json — so the check itself can be audited later by someone who was not here.

Discovered
check_entity

Verify a legal entity: does this company exist, under which identifier and jurisdiction, and is its registration current? Cited to open primary registers (the GLEIF LEI index and US SEC EDGAR). Returns found, ambiguous, not_found or unknown; a near name match is never reported as a match. Not advice, not a credit check, not a sanction screen. Comes with an Ed25519-signed receipt covering the question, the verdict, the sources and the time, checkable offline against the published key at /.well-known/factstamp-issuer.json — so the check itself can be audited later by someone who was not here.

Discovered
check_entity_file

The entity file: ONE paid answer holding everything we hold about one company: the whole picture in ONE call rather than four separate facts stitched together, at the point of signing, onboarding, paying or acquiring a counterparty. It holds identity and standing, the registered office, SIC activity and previous names, the filing position, a sanctions screen across our six lists, and the ownership the registers publish (the persons with significant control where a register publishes them, and the declared parent relationships where a company has an LEI, with beneficial ownership stated as not public in nearly every country we cover) — each cited to the register it came from with its retrieval time — plus ONE coverage block naming every register consulted and every one NOT consulted. Returns found, ambiguous, not_found or unknown for the company itself; a register that was not read is named as not read, never guessed. 33p UK-facing, settled in USDC at the dated rate. Not advice, not a credit check. Comes with an Ed25519-signed receipt covering the question, the verdict, the sources and the time, checkable offline against the published key at /.well-known/factstamp-issuer.json — so the check itself can be audited later by someone who was not here.

Discovered
check_entity_file_ca

Canadian company lookup and Canadian federal corporation register check by nine-digit Business Number (BN) only: corporation number, BN, governing legislation, every registered name with type, current flag and effective date, the register's own status, the registered address, the MINIMUM and MAXIMUM NUMBER of directors as a count rather than the people, and the annual-return history with dated incorporation and other activities, in six sections from one live read of Corporations Canada, with one signed receipt and one coverage block. The public endpoint is keyed by Business Number, so a name alone cannot reach it; provincial and territorial corporations are a different register this file does not read; director and officer names and beneficial owners are not published on this path. Returns found, not_found or unknown; unknown is a first-class answer and is not charged. Not advice, not a credit check and not a KYB service. Comes with an Ed25519-signed receipt covering the question, the verdict, the sources and the time, checkable offline against the published key at /.well-known/factstamp-issuer.json — so the check itself can be audited later by someone who was not here.

Discovered
check_entity_file_il

Israeli company lookup and company register check by company number (nine digits, with its own check digit) or by registered name, Hebrew or English: identity, corporation type, the register's own status and sub-status, description and stated purpose, incorporation date, government-company flag and restrictions, last annual-report year and the structured registered address, in seven sections from one live read of the Registrar of Companies dataset on data.gov.il, with one signed receipt and one coverage block. No officers, directors, shareholders or beneficial owners as people, and no financial statements: those sit behind the Registrar's paid company extract, which this file does not read. Amended returns and a change registered after the dataset's last refresh may not yet appear. Returns found, ambiguous, not_found or unknown; unknown is a first-class answer and is not charged. Not advice, not a credit check and not a KYB service. Comes with an Ed25519-signed receipt covering the question, the verdict, the sources and the time, checkable offline against the published key at /.well-known/factstamp-issuer.json — so the check itself can be audited later by someone who was not here.

Discovered
check_figure

Submit the dated figure you are about to act on. Returns verified, stale, contradicted or unknown, cited to the publisher's own series with its as-of date. Relevant wherever a number is going onto a page, deck or decision. Not advice. Comes with an Ed25519-signed receipt covering the question, the verdict, the sources and the time, checkable offline against the published key at /.well-known/factstamp-issuer.json — so the check itself can be audited later by someone who was not here.

Discovered
check_sanctions

Sanctions screening of a name, for whether a person or company is on a sanctions list — and which one. Reads OFAC SDN, the UN consolidated list, the EU Financial Sanctions File and the UK Sanctions List, and returns listed, mismatch, not_found or unknown. The answer names the lists that were consulted with each one's retrieval date (and the UK list's own report date); a list that was not consulted is named as not consulted, and unknown is the answer when we cannot tell. A near name is never reported as the same party, and a listed verdict stands even when another list was not consulted. Not advice, not a legal determination. Comes with an Ed25519-signed receipt covering the question, the verdict, the sources and the time, checkable offline against the published key at /.well-known/factstamp-issuer.json — so the check itself can be audited later by someone who was not here.

Discovered
check_vat

An EU VAT number check — VAT validity, and the VAT registration behind it. Reads the official VIES service (European Commission), keyless. Returns valid, invalid or unknown — an outage is NEVER reported as invalid — with the member state, the register's own request date, and the trader identity only where that member state discloses it. Some member states disclose nothing; the answer says so rather than showing an empty string. GB is out of scope after Brexit (XI, Northern Ireland, is covered). Not tax advice, not a credit check. Comes with an Ed25519-signed receipt covering the question, the verdict, the sources and the time, checkable offline against the published key at /.well-known/factstamp-issuer.json — so the check itself can be audited later by someone who was not here.

Discovered
list_card_packages

Included. The one-off card packages as one machine-readable catalogue: the 11 products and their 13 prices in Australian dollars, the unit one payment buys for each SKU, what the package returns, and where the input is sent. One payment each, nothing metered, nothing subscribed. The per-call doors stay open beside them.

Discovered
list_series

Included. What this engine covers, the publisher and as-of date behind each series, and the no-guess rule.

Discovered
route_claim

Included. Shows which series a claim would be routed to, the value and date extracted, and the signals behind the score. Returns NO verdict — pay for check_figure when you want one.

Discovered
verify_bulk

Check a whole list in one call: a bibliography or a dependency manifest. Send items[] of {tool, input} or the citations[]/packages[] shorthand. Up to 12 items at a flat US$0.12 on this door; longer lists pay 0.016667 an item on the pack-funded HTTP door (POST /bulk, up to 25 items). Every item is answered by the same door that answers a single call, so the verdicts cannot disagree. This door takes a LIST of references or package versions, not prose: to check the claims inside a document, use check_document, and to check one reference use verify_citation or verify_package. Comes with an Ed25519-signed receipt covering the question, the verdict, the sources and the time, checkable offline against the published key at /.well-known/factstamp-issuer.json — so the check itself can be audited later by someone who was not here.

Discovered
verify_citation

Says whether a citation can be repeated. Submit a DOI, an arXiv ID or a paper title: returns whether it exists, what it is (title, authors, year, container) and whether it has been retracted, cited to Crossref and arXiv. Optionally send what your document claims (title, authors, year, journal) and every field is compared one by one — a disagreement is reported as mismatch, never as verified. A near title match is never reported as verified; a title that is absent from both returns not_found. Not advice. Comes with an Ed25519-signed receipt covering the question, the verdict, the sources and the time, checkable offline against the published key at /.well-known/factstamp-issuer.json — so the check itself can be audited later by someone who was not here.

Discovered
verify_package

Reports on a dependency at the point of installation. Submit a package and version plus its ecosystem: returns whether that exact version exists, whether it is yanked or deprecated, and every advisory OSV lists against it. An invented version returns not_found with the real versions nearest to it, and an invented name returns the published names that look like it — which is the point, because that is how slopsquatting gets installed. Not a security audit. Comes with an Ed25519-signed receipt covering the question, the verdict, the sources and the time, checkable offline against the published key at /.well-known/factstamp-issuer.json — so the check itself can be audited later by someone who was not here.

Discovered
watch_add

Watch ONE citation or ONE package version instead of checking it once. Send kind ('citation' or 'package') and the subject (a DOI, an arXiv ID or a title; or npm:express@4.18.2). The first check is answered immediately and signed, then re-checked daily for 30 days; every real change (a retraction, a new advisory, a yanked version) is recorded with its own signed receipt. Returns a read URL and a token shown once; optionally send an https webhook and each change is POSTed to it. For a whole list of references under one purchase use watch_portfolio; for a one-off answer that does not need watching, use verify_citation or verify_package. Comes with an Ed25519-signed receipt covering the question, the verdict, the sources and the time, checkable offline against the published key at /.well-known/factstamp-issuer.json — so the check itself can be audited later by someone who was not here.

Discovered
watch_portfolio

Watch a whole list instead of one reference at a time: up to 25 citations or package versions re-checked every day for 30 days under one token. US$5 a portfolio — 20 cents a reference, under a cent a check — and the first check on every reference is answered and signed immediately. Each real change carries its own signed receipt, and nothing is sent when nothing changed. ONE purchase covers the whole list: for a single subject on its own, use watch_add. Returns a read URL and a token shown once. Comes with an Ed25519-signed receipt covering the question, the verdict, the sources and the time, checkable offline against the published key at /.well-known/factstamp-issuer.json — so the check itself can be audited later by someone who was not here.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected609 ms18
Connected625 ms18