Terms of Service

These terms govern the use of the Market Zeitgeist services: the Pro application (scanners and analyzer), the Cycles API and the MCP server, and the Cycles IQ membership. They apply to every account created through the Market Zeitgeist sign-in and to every order placed under the brand. The website itself and the research newsletter on Substack can be used without an account; the newsletter is subject to Substack's own terms.

1. Provider and scope

Provider is WhenToTrade, owner Lars von Thienen, Bredbeekskoppel 6, 21266 Jesteburg, Germany (imprint). MarketZeitgeist and Cycles IQ are brands of WhenToTrade. These terms apply to consumers and to business customers. Deviating terms of the customer do not apply unless the provider agrees to them in writing. For Cycles IQ members, the individually agreed offer and the signed non-disclosure agreement take precedence over these terms where they differ.

2. The services

Pro application: prepared scanner pages for markets and assets and the analyzer web app for the customer's own symbols and timeframes, provided as a subscription.
Cycles API and MCP server: programmatic access to cycle detection, cyclic indicators, phase and consensus scores and cycle projections, through REST endpoints and through the MCP server for AI clients. Access is provided on usage-based plans with a monthly allowance and rate limits stated in the plan description at the time of ordering.
Cycles IQ membership: the full stack for practitioners, comprising full API and MCP access, the Cycles AI skills, the advanced analyzer application, pre-built applications and dashboards, feature updates, maintenance and support, an individual onboarding session and ongoing sessions with Lars von Thienen, as described in the individual offer.

All services deliver measurements and model-based projections of cycles found in data. They are research and analysis tools. They are not investment advice and do not take the customer's personal circumstances into account; the risk notice in the imprint is part of these terms.

3. Account and sign-in

Use of the Pro application, the API, the MCP server and the Cycles IQ materials requires an account. Sign-in is provided through an identity service (Auth0); the customer may use an e-mail address with a password or a supported social or enterprise login. One account per person. The customer keeps credentials, API keys and access tokens confidential, does not share them, and informs the provider without delay if they may have become known to third parties. Everything done under the customer's account or with the customer's keys is attributed to the customer until the provider has been informed. The customer must be at least 18 years old.

4. Conclusion of contract

Pro subscriptions and API plans are ordered online. The order is an offer; the contract is concluded when the provider confirms the order by e-mail or activates the service, whichever comes first. Cycles IQ membership is concluded on the basis of an individual written offer, which the customer accepts by countersigning it or by paying the joining fee, together with the signed non-disclosure agreement. The contract language is English. The provider stores the text of the contract and sends it to the customer with the order confirmation.

5. Prices and payment

Prices are stated in the online plan description or in the individual offer. Prices for consumers include German VAT; prices for business customers are stated net plus applicable VAT. Usage-based plans are billed monthly in arrears for the allowance and, where the plan provides for it, for usage above the allowance at the stated rate. Subscriptions are billed monthly in advance. The Cycles IQ joining fee is due on conclusion of the membership, the annual service and update fee at the start of each membership year. Payment is made through the payment provider named during the order or by bank transfer against invoice. Invoices are due on receipt. If a payment fails or is overdue, the provider may suspend access after a reminder until the outstanding amount is settled; the obligation to pay remains.

6. Term and termination

Pro subscription and API plans run for one month and renew automatically for a further month unless cancelled. They can be cancelled at any time with effect from the end of the current billing month, in the account settings or by e-mail. Usage already consumed in the current month remains payable.

Cycles IQ membership consists of a one-time joining fee and an annual service and update fee. The membership has an initial term of twelve months. It renews for a further twelve months unless cancelled with one month's notice before the end of the current membership year. Where the member is a consumer, the membership continues for an indefinite period after the initial term and can then be cancelled at any time with one month's notice; an annual fee already paid is refunded pro rata for the months after the cancellation takes effect. The joining fee is not refunded on termination.

The right of both parties to terminate for cause remains unaffected. Cause exists in particular if the customer breaches the fair-use rules in section 7, shares credentials or keys, breaches the non-disclosure agreement, or is more than thirty days in default with a payment after a reminder. On termination, access to the services ends, API keys are revoked, and the customer stops using the Cycles IQ materials; confidentiality obligations survive termination.

7. Fair use of the API and the MCP server

The API and the MCP server are shared infrastructure. Each plan states a monthly allowance and rate limits (requests per minute and per day); requests above the rate limits are answered with an error and do not accrue charges. The following rules apply to all plans and to Cycles IQ membership:

Keys and tokens are personal to the customer's account and are used only in the customer's own applications, scripts, dashboards and AI clients, for the customer's own analysis or the internal use of the customer's organisation as stated in the plan.
Raw results of the API (time series, cycle tables, indicator values) are not resold, redistributed, made publicly available as a data feed, or used to operate a service that offers cycle analysis to third parties. Publishing charts, readings and conclusions derived from the results is permitted with a reference to Market Zeitgeist.
No automated bulk harvesting of the service beyond the plan, no circumvention of rate limits, no parallel accounts to multiply allowances, no interference with the operation or security of the service.
No reverse engineering, decompiling or reconstruction of the cycle engine, the skills or the applications, and no use of the results to train a substitute for them.
No unlawful use, and no use in breach of the terms of the data sources the customer connects (for example exchange or charting providers).

Where usage indicates a breach, the provider may throttle or suspend access first and contacts the customer. Repeated or serious breaches are cause for termination under section 6.

8. Availability, maintenance and changes

The provider operates the services with due care and aims for continuous availability, but does not guarantee uninterrupted operation. Maintenance windows, updates and changes to endpoints are announced in the documentation or by e-mail with reasonable lead time; backwards-incompatible changes to the API are announced at least sixty days in advance except where security requires an immediate change. The provider may extend, modify or discontinue individual features, provided the core of the service ordered remains available for the term paid for. Market data from third-party sources is provided as received; the provider is not liable for its accuracy or continuity.

9. Intellectual property and licence

The cycle engine, the applications, the API, the MCP server, the skills, the documentation, the pre-built applications and dashboards and all related materials remain the property of the provider. For the term of the contract the customer receives a non-exclusive, non-transferable licence to use them within the scope of the plan or membership. Results generated by the customer with the services, and applications the customer builds on the API and the skills, belong to the customer; the underlying engine, skills and materials stay licensed, not sold. Pre-built applications and dashboards supplied to Cycles IQ members may be modified and used in the member's own products, but not passed on as such to third parties.

10. Confidentiality

Cycles IQ materials, the skill repository, methodology details and everything marked confidential are trade secrets of the provider. Members treat them as confidential during and after the membership. The signed non-disclosure agreement governs the details and prevails over this section.

11. Right of withdrawal for consumers

Consumers have a statutory right to withdraw from an online order within fourteen days without giving reasons. The period starts on the day the contract is concluded. To withdraw, the consumer sends a clear statement (for example an e-mail) to lars@marketzeitgeist.com; sending the statement before the period expires is sufficient. Payments received are refunded within fourteen days using the original means of payment. If the consumer has asked for the service to begin during the withdrawal period, a proportionate amount for the service provided until withdrawal is payable. For access that is activated immediately at the consumer's express request and with the consumer's acknowledgement that the right of withdrawal is thereby lost, the right of withdrawal expires on activation.

12. Liability

The provider is liable without limitation for intent and gross negligence, for injury to life, body or health, under the Product Liability Act, and for guarantees expressly given. For simple negligence the provider is liable only for breach of an obligation whose fulfilment is essential to the contract and on which the customer may rely (cardinal obligation), and then only for the foreseeable damage typical of the contract; this liability is limited to the fees paid by the customer in the twelve months before the event. The provider is not liable for trading or investment losses, lost profits or consequential damage arising from decisions the customer makes on the basis of the services; the services deliver measurements and projections, and the decision and its risk remain with the customer. The customer is responsible for backing up data and results.

13. Data protection

The provider processes personal data as described in the privacy policy. Where the customer processes personal data of third parties through the services, the customer is responsible for the lawfulness of that processing.

14. Changes to these terms

The provider may change these terms with effect for the future where this is necessary because of changes in the law, in the services, or in the technical environment, and the change is reasonable for the customer. Changes are announced by e-mail at least four weeks before they take effect. If the customer does not object before that date, the changes apply; the provider points this out in the announcement. If the customer objects, the contract continues under the previous terms and either party may terminate it with effect from the date the changes take effect.

15. Final provisions

German law applies, excluding the UN Convention on Contracts for the International Sale of Goods. For consumers, the mandatory consumer-protection provisions of the country of their habitual residence remain unaffected. If the customer is a merchant, a legal entity under public law or a special fund under public law, or has no general place of jurisdiction in Germany, the exclusive place of jurisdiction is the seat of the provider in Jesteburg, Germany. The European Commission provides a platform for online dispute resolution at ec.europa.eu/consumers/odr; the provider is neither willing nor obliged to participate in dispute resolution proceedings before a consumer arbitration board. Should a provision of these terms be invalid, the remaining provisions stay in force. This English version is the binding version.

Last updated: 12 September 2026.