Terms of Use
The Leash Index is published by Media Yard LLC. By using it, or by submitting a server to it, you agree to these terms.
What the index is
The index classifies MCP servers by what their tools/list manifests declare, using the method published on the
methodology page. Scores, bands and findings are the output of that method applied to a
manifest on the date shown. They are opinions derived from disclosed rules and disclosed inputs.
They are not statements about how any product behaves, whether it is secure, or whether it provides controls outside MCP. A product can offer revocation, expiry, audit logs or spending limits that a manifest has no way to declare and the index cannot see. Nothing here is a certification, a security audit, a penetration test, or professional, legal or security advice.
No reliance, no warranty
The index is provided as is and as available, without warranties of any kind, express or implied, including accuracy, completeness, fitness for a particular purpose and non-infringement. Classifications are made by rules that are known to misread some tools, as the methodology discloses. Do not rely on the index as the sole basis for any decision.
Limitation of liability
To the fullest extent permitted by law, Media Yard LLC is not liable for any indirect, incidental, special, consequential or punitive damages, or any loss of profits, revenue, data or goodwill, arising from the index or from reliance on it. Where liability cannot be excluded, it is limited to the greater of the amount you paid Media Yard LLC for use of the index in the prior twelve months or one hundred US dollars. Some jurisdictions do not allow these limits, so they may not apply to you.
Buying a stack report
The report is sold through Link, by Stripe, which is the merchant of record for the sale. Stripe takes the payment, calculates and collects any sales tax, VAT or GST, issues your receipt and any tax invoice, and answers questions about the transaction itself. Your card statement and your receipt name Link, not Media Yard LLC. Media Yard LLC supplies the report, and everything below about what the report is remains ours. Stripe's terms govern the payment; these terms govern the report.
The price shown includes any tax due, so it is the whole amount you pay. Stripe may show it converted into your local currency. Prices may change; a change never affects a report already bought.
The report is generated in your browser from the index as it stands on the day you generate it, and covers only the servers the page's free preview lists as covered. Your purchase unlocks the report on the device you bought it on for 30 days, during which you can generate it as often as you like. It is for your own use and for sharing with people reviewing your systems; it may not be resold or used to publish a competing index.
If the report does not generate, or does not cover what the preview showed, ask for a refund within 14 days of purchase. You can email support@leashkit.com, or ask through the receipt Link sent you. A request made through Link reaches us first; if we do not answer it within 48 hours, Stripe decides it under its own refund policy. If you are a consumer in the UK or EU, you also have a statutory right to withdraw within 14 days, which we do not ask you to waive — see UK and EU consumer rights.
The report is subject to the same limits as the index: it describes what manifests declare, it is not a certification, and the sections on reliance and liability above apply to it.
Buying a pre-publish check
The pre-publish check is sold the same way and on the same terms as the stack report: through Link, by Stripe as merchant of record, at a price that includes any tax, unlocked on the device you bought it on for 30 days, with the same refund within 14 days if it does not work as the page describes, and the same statutory right of withdrawal. It is computed in your browser from the manifests you paste, which are never sent to us, and from a count of how many listed servers sit at each exposure score on the day the page was built.
The check tells you how a manifest would read in the index. It does not change, reserve or promise any listing, score or ranking, it is not a certification, and it is subject to the same limits as the index.
Buying a data licence
The data licence is sold through Link, by Stripe as merchant of record, at a price that includes any tax, as a single payment with no automatic renewal. It gives you access to the dataset files described on that page, and to each weekly refresh of them, for 365 days from purchase on the device you bought on.
Media Yard LLC grants you a non-exclusive, non-transferable licence to load the files into your own systems, to analyse them, and to use them and what you derive from them inside your own products and services, including commercial ones. You may not resell or redistribute the files or a substantially complete copy of them, or use them to publish a public index that substitutes for this one. Files you downloaded while your access lasted remain licensed to you on these terms afterwards. Nothing in the licence transfers ownership of the dataset, and the manifests it contains remain the work of the servers that published them.
The dataset records what manifests declared on the dates shown. It is not a certification or a security assessment, it may contain errors and gaps, and the sections on reliance and liability above apply to it. If the files do not download, or are not what the page describes, ask for a refund within 14 days of purchase in the same way as for a report. The licence is sold on these terms only: there is no signed or negotiated version.
Subscribing to Guard Team
Guard Team is sold through Link, by Stripe as merchant of record, at a price that includes any tax, as a subscription billed each month or each year until you cancel. It is the only thing sold here that renews. You can cancel at any time from the Guard Team page, through Link, by Stripe from the receipt you were emailed, or by writing to support@leashkit.com; a cancelled subscription runs to the end of the period already paid for and is not charged again.
What you buy is a signed licence that switches on the team features of Leash Guard: a shared policy, receipts written to a location you name, and alerts to a webhook you name. The licence is checked on each machine and is renewed there while the subscription is paid, plus 7 days. It covers one team or organisation, with any number of people and machines in it; it may not be shared with or resold to another organisation. The Guard software itself remains under its own open-source licence.
Your policy, your receipts and your alerts are stored and delivered by services you choose and control. Media Yard LLC does not receive them, cannot recover them and is not responsible for the storage or webhook you point Guard at. When a subscription ends, machines stop fetching the shared policy and stop writing receipts to your storage; limits already fetched stay in force on each machine.
Guard enforces the limits you set on the calls that pass through it. It is not a guarantee that an agent or a server behaves well, it does not see calls that do not pass through it, and the sections on reliance and liability above apply. If it does not work as its page describes, ask for a refund within 14 days of a payment in the same way as for a report, and the statutory right of withdrawal applies to the first payment in the same way.
Leash Grant
Leash Grant is free while it is new, and may later be charged for; nothing already issued will be charged for after the fact. A product sends its customer to a page on this site that states what the product's agent is asking to do. If the customer approves, Media Yard LLC signs a grant recording the limits the customer chose and returns it to the product.
A grant is a signed record of what a customer allowed. Media Yard LLC is not a party to the arrangement between a product and its customer, is not in the path of the agent's actions, and does not enforce a grant: the product that receives it is responsible for checking it before its agent acts, for asking whether it has been revoked, and for everything its agent does. The name a product gives on the consent page is that product's own statement and is not verified; the page shows the address the customer will be returned to, and a customer should approve only if they recognise it.
A product may send Media Yard LLC a log of what its agent did under a grant, for the customer to read. The log is the product's own account. Media Yard LLC checks that entries already received have not been altered and does not check that the log is complete or accurate; an action a product did not report does not appear. A product that sends a log must not put personal data in it.
Where a customer chose to be asked before an action, a product may leave a request and the customer may approve or refuse it from their grant page. An approval is the customer's yes to one action, passed on as given. Media Yard LLC does not notify the customer, does not check that a product acts on an approval only once, and is not responsible for what a product does with one.
A customer may switch a grant off, and read any log sent for it, at any time with the link they are given on approval. Whoever holds that link can use it, so it should be kept private. A revocation is published within about a minute; Media Yard LLC does not promise that a product will act on it. The sections on reliance and liability above apply.
How listings are made
The index lists the servers published in the official MCP registry, and a short list of vendors' published servers. A server
with a public endpoint is asked, without signing in, to list its tools: a handshake and one tools/list request, about
once a week, never more than one request at a time to the same host, and never a call to any tool. A server that ships only as a
package — on npm, on PyPI or as a container image — is read by running that exact published version in an isolated container with no
network access and only placeholder credentials, and asking it the same question. A given version is read once. Where a package could
only be read with one of its dependencies held at an earlier version, its page says so.
The index also records the date the registry first listed each server and, for an endpoint that did not list its tools, what it returned instead and since when, on the unanswered ledger. A ledger entry describes one response to one anonymous request on the date shown. It is not a statement that a product is unavailable, closed, faulty or withdrawn.
Names and marks
Product and company names identify the servers described and belong to their owners. Their use does not imply affiliation with, sponsorship by or endorsement of Media Yard LLC or the index. The index does not display third-party logos.
Corrections
A maintainer can correct a listing by submitting the current manifest and proving control of the origin the listing was verified from. Corrections are published alongside the record they correct, never over it. Anyone who believes a listing or a ledger entry is inaccurate, or who wants one removed, may also write to support@leashkit.com. The Privacy Notice sets out the rights of anyone a registry record names.
Submission Terms
These additional terms apply when you submit a server.
- Authority. You confirm that you maintain the server, that you are authorised by its owner to submit it,
and that the manifest is the server's genuine
tools/listresponse. - Licence. You grant Media Yard LLC a worldwide, non-exclusive, royalty-free, perpetual licence to store, reproduce and publish the manifest, and to publish the scores, classifications and findings derived from it, including in the record history of the listing.
- Accuracy. You will not submit a manifest that is false, altered to mislead, or that belongs to a server you do not maintain. You are responsible for losses caused by a submission that breaches these terms.
- Discretion. Media Yard LLC may decline, delay or remove any submission or listing. Submitting does not guarantee a listing, a particular score, or any change to an existing one.
- Your contact details are handled as described in the Privacy Notice.
Changes
These terms may change. The version in force is the one published here, with the date below.
Governing law
These terms are governed by the laws of the State of New Jersey, without regard to conflict-of-laws rules.