Terms of Service

01Who these terms cover

These terms are a contract between you and Tensegrity Systems LLC, Seattle, Washington, United States (“Tensegrity”, “we”, “us”). They apply when you browse this site, join the waitlist, create or use a Foundations account, call our HTTP or MCP APIs, or pay for a lookup with x402.

If you use Foundations for an organization, you confirm you can bind that organization, and “you” includes it. You must be at least 16 and using Foundations for professional or business purposes. Do not use the services if you cannot agree to these terms.

02The services

Foundations is a set of products we operate: Personas, Elements, this marketing site, and the APIs at foundations.tensegrity.works. Some surfaces are public. Others are invite-only or paid.

• – This site describes the products and collects waitlist and demo requests.
• – Elements is a UI encyclopedia: kinds, specs, and related derived data for people and agents.
• – Personas is a workspace for synthetic audience work, when we have given you access.
• – APIs. HTTP glossary routes can answer with x402. POST /mcp needs an account. Human docs: /docs. Agent docs: /docs, /llms.txt, /openapi.json, /pricing, and /terms on the API host.

Features, prices, and which paths are free can change. The live 402 challenge and API pricing are the source of truth for a given call.

03Waitlist, invites, and accounts

Joining the waitlist asks us to consider you for access. It does not create an account, reserve a seat, or require us to invite you. We can close, ignore, or delete a waitlist entry.

Accounts, when we issue them, are for the person or organization we invite. Keep sign-in details and tokens to yourself. You are responsible for activity under your account, including calls your agents make. Tell us promptly if you think the account is compromised.

We may refuse, limit, or reclaim access if these terms are broken, if payment fails, or if we have to protect the service or other users.

04Catalog and lookups

The Elements catalog — kinds, slugs, aliases, briefs, spec bodies, glyphs, machines, atlases, and the way they are arranged — is owned by Tensegrity. Joining the waitlist or paying for a lookup does not transfer that ownership.

A successful paid call buys one response for that URL. Kind lists return slugs, aliases, complexity, atomic type, and tier for one kind. Specs return the glossary body for one term. A settled x402 call is a Pro grant: Pro slugs and Pro fields. Max slugs need a Max account. The free kinds table is not billed. A lookup does not grant an account, glyphs, machines, derived APIs, credits, or redistribution rights. Catalog entries can change or be retired. The short machine-readable version of this is at foundations.tensegrity.works/terms.

You may:

• – Use what you learn from a spec or kind list to design and build interfaces, including with an agent.
• – Quote short excerpts with attribution when that is fair use or otherwise allowed by law.
• – Cache a response only as long as you need it to finish that task, not as a substitute catalog.

You may not:

• – Republish, sell, or host the catalog, or a substantial part of it, as a competing encyclopedia or dataset.
• – Train or fine-tune a model on the catalog for others to use as a substitute for Elements.
• – Bypass payment, strip PAYMENT-REQUIRED, or harvest paths we have not made free.

05Your workspace

You retain rights in content you put in a Foundations workspace: personas, findings, and component work you add. You grant us a license to host, process, and display that content only to run the service for you, including for agents you authorize.

Personas are meant to be synthetic. Do not put personal information about identifiable real people into persona content unless you have a lawful basis. You are responsible for the lawfulness of what you store and of how you use outputs.

We do not use your workspace content to train general-purpose AI models. Details are in the Privacy Policy.

06Agents and MCP

You may connect MCP clients and other agents to Foundations. Those clients act with your permissions. We treat their requests as yours. POST /mcp requires a signed-in account. HTTP glossary routes can accept x402 without an account.

You are responsible for what an agent reads, writes, or pays for under your credentials. Revoke a client you no longer trust. Do not share bearer tokens or payment keys. We are not a party to your agreement with any agent vendor.

07Billing and payments

Some lookups and account features cost money. Account holders use credits and, when offered, card subscriptions or packs through Stripe. Agents without an account can pay per HTTP lookup with x402. This section is the contract for metering and paid access.

• – Account credits. Signed-in tools spend credits. Credits have no cash value, are not transferable between accounts, and expire by grant type. Spend is FIFO by soonest expiry, with subscription allowance before purchased credits. At zero credits, metered tools hard-stop until you buy a pack or a new allowance arrives. Auto-recharge is not offered in v1. Unused credits are not refunded when an account closes, a period ends, or a subscription cancels, except where the law requires it or we made a billing error.
• – Subscriptions (Pro / Max). Paid subscriptions grant an entitlement plus allowance credits for that billing period (Pro 500, Max 1000). They auto-renew until you cancel. Cancel anytime in the billing portal or by emailing support; you keep the paid entitlement through the end of the paid period, then the account returns to Starter unless you hold a Lifetime term. Allowance credits expire at period end and do not roll over.
• – Lifetime. Lifetime Pro means entitlement=pro and term=lifetime; Lifetime Max means entitlement=max and term=lifetime — both for the operational lifetime of the Foundations Elements product, not the buyer’s lifespan. They are non-transferable. Metered credits are still required; Lifetime is not unlimited use. Buying Lifetime cancels any open Pro/Max subscription. We may suspend or end Lifetime access for abuse, breach of these terms, or to protect the service. We do not guarantee that any specific feature set will remain available forever.
• – Packs and promos. Purchased credit packs (100 / 500 / 1000) expire twelve months after grant. Promo codes redeem once per account for signed-in users; we may disable a code at any time.
• – Card payments. Card charges are processed by Stripe. We do not store full card numbers. Receipts and billing notices go to the account email.
• – x402. HTTP kind lists and specs can require a PAYMENT-SIGNATURE. Payment is x402 v2 exact scheme in USDC on Base (eip155:8453). A facilitator we name in the challenge, currently facilitator.xpay.sh, verifies and settles; we may also settle through Coinbase CDP without changing the live accepts[] payTo. We do not custody your wallet. Kind lists are 0.01 USDC; search and specs are 0.02 USDC, unless the live accepts[] array says otherwise. GET /mcp/start is a free briefing. Settled x402 is a Pro grant.

A settlement that returns 200 and a PAYMENT-RESPONSE is final. An expired, invalid, or rejected authorization is not a charge. We do not refund a delivered lookup because you dislike the entry or because the catalog later changes. Network fees charged by your wallet or chain are yours.

Fair use applies to all paid and Lifetime access. We may rate-limit, suspend, or reclaim access for abuse, unpaid charges, or risk to the service or other users.

08Acceptable use

Do not use Foundations to:

• –Break the law, or store or send illegal content.
• –Attack, overload, or probe the service except through documented paid or free routes.
• –Interfere with Browser Integrity Check, payment, or authentication except as we document for agents on API paths.
• –Impersonate us, misrepresent an affiliation, or resell access without a written deal.
• –Violate someone else’s rights, including by putting their personal data in a persona without a basis.

Automated clients are welcome on the documented API paths. They still have to pay or authenticate when the path requires it, and they still have to follow this section.

09Availability

We provide Foundations as-is. Invite-only features can stay closed. We do not promise uptime, a review outcome on a directory listing, or that a given spec will stay at the same URL or price.

We may change, suspend, or stop any part of the service, including retiring a kind or a slug. If we discontinue a paid feature you prepaid in credits, we will say so and, where it is reasonable, convert or expire those credits on notice.

10Disclaimers and liability

Specs, glyphs, and examples are reference material. They are not a warranty that your interface will be accessible, safe, fit for a regulated use, or free of third-party claims. You remain responsible for what you ship.

To the fullest extent the law allows, we disclaim implied warranties of merchantability, fitness for a particular purpose, and non-infringement. We are not liable for lost profits, lost data, replacement costs, or indirect, incidental, special, consequential, or punitive damages.

Our total liability for a claim arising out of Foundations is limited to the greater of one hundred U.S. dollars or the amounts you paid us for the services that gave rise to the claim in the twelve months before it. These limits apply even if a remedy fails its essential purpose, except for death or personal injury caused by our negligence, fraud, or liability the law does not let us limit.

11Termination

You may stop using the site and, if you have an account, ask us to close it by emailing support@tensegrity.company. We may suspend or end access immediately for a breach, abuse, unpaid charges, or legal risk.

After the account ends, sections 04, 05, 07, 10, and 12 still apply. A lookup we already delivered stays delivered; the license in section 04 does not grow after termination.

12Law, changes, and contact

These terms are governed by the laws of the State of Washington, without regard to conflict-of-law rules. Exclusive venue is the state or federal courts in King County, Washington, except that we may seek injunctive relief in any court for misuse of the catalog or the service.

If we make a material change, we will post the new terms here and, for account holders, notify the account email at least 14 days before the change takes effect. The date at the top of this page is the last update. Continuing to use Foundations after that date is acceptance. If you do not agree, stop using the services and close the account.

Questions: support@tensegrity.company, or write to Tensegrity Systems LLC, Seattle, Washington, United States.