Lemma is a local-first MCP server for AI coding agents such as Claude Code, Cursor and Windsurf. It cuts what enters the model's context (repeated reads, command output, unused tool schemas), stores memories next to the hashes of the files they came from so changed code makes them STALE, and keeps a ledger of what it actually saved.

How is the Brain different from a semantic cache?

A semantic cache returns an old answer when a new question looks similar. The Brain stores each memory with hashes of its source files and serves it only while they still match; every result says whether it is a hit, a near-miss or stale.

Yes. 60 of its 110 tools are free, including the whole memory lifecycle and the token ledger. Pro is $5 per month and adds the tools that write, run commands, refactor and review pull requests.

Is Lemma open-source?

The core is MIT-licensed and published on npm as @nxuss/lemma. Pro features require a license.

Lemma is built and maintained by Nxus Studio in Guadalajara, Jalisco, Mexico.

Terms of Service

Last updated: 2026-11-01 · This is a translation. The Spanish version governs.

These terms govern your use of Lemma: the @nxuss/lemma npm package, the Pro features and the Lemma Cloud service. Lemma is a product of Nxus Studio, operated by Juan Carlos Díaz Mendoza, an individual ("Nxus Studio", "we"). By installing Lemma, activating a license or using a Lemma Cloud key you accept these terms. If you accept them on behalf of a company, you confirm you are authorized to bind it.

1. What each thing is

Lemma (free): the open-source MCP server under the MIT license. It runs on your machine and its use is governed by that license; these terms only add what it does not cover.

Lemma Pro: additional features of the same package, unlocked with a paid license.

Lemma Cloud: a shared Brain we host so a team's agents read and write the same memories. It is used with one key per developer and includes Pro for every seat.

2. Accounts, keys and seats

Each Lemma Cloud key belongs to one person on your team. Do not share it or commit it to a repository, and revoke it from the console or by writing to us when someone leaves. You are responsible for what is done with your workspace's keys.

Your plan sets how many seats, memories and requests it includes. Past a limit the service refuses the operation with a clear error; we never bill overages without telling you first.

3. Prices, trials and payment

Current prices are shown at lemma.nxus.studio. Charges are made in advance, monthly or yearly depending on the plan, through Stripe. We never store your card details.

Free trials last as long as the offer says. If you do not cancel before it ends, the plan's billing starts.

Founder price: the first teams accepted keep their price for 12 months from the first charge, as long as the subscription stays active. Their limits are more generous than the general public's; limits for teams that sign up later may differ.

We may change prices and limits with at least 30 days' notice by email. The change applies from the next period; if you disagree, you can cancel before then.

Prices exclude taxes unless stated otherwise. If you need a Mexican tax invoice (CFDI), ask juan.carlos@nxus.studio with your tax details.

4. Cancellation and refunds

You can cancel at any time from the billing portal or by writing to us. Cancellation takes effect at the end of the period already paid, with no pro-rated refunds, unless applicable law requires one or the service failed through our fault.

If a payment fails, the workspace keeps its plan while Stripe retries the charge. If the retries run out and the subscription is cancelled, the workspace drops to the free plan and its limits.

5. Your content

The memories, file paths, repository names and other content your agents store in Lemma Cloud are yours. You grant us only the permission needed to store, process and return them to you and your team. We do not use them to train models, we do not sell them, and we do not read them except to support you when you ask or when the law requires it.

Lemma tries to mask secrets (keys, tokens, passwords) before storing a memory, but that filter is not perfect. Do not knowingly store secrets, third parties' personal data or anything you have no right to share with your team.

Anything a member of your workspace stores is visible to the other members of that workspace. That is how a shared Brain works.

You can delete memories at any time and ask us for a full export of your workspace. When you cancel you can ask us to delete your whole workspace; we do so within 30 days, plus the time it takes backups to rotate out (7 days).

6. Acceptable use

Do not use Lemma for illegal activity, to attack or overload the service, to get around plan limits or license checks, or to resell access to Lemma Cloud without a written agreement with us. We may suspend a key or workspace that puts the service or other customers at risk, telling you as soon as we can.

7. Availability and changes

Lemma Cloud is offered in its founder stage: we look after it and back it up daily, but there is no written service-level agreement (SLA) unless we sign one separately. Local Lemma keeps working when Lemma Cloud is unavailable.

We may improve, change or retire features. If we retire Lemma Cloud entirely, we will give you at least 60 days' notice to export your content and refund the unused part of any period paid in advance.

8. Warranties and liability

Lemma is provided "as is". The memories and suggestions it gives your agent are aids, not facts: review what your agent changes before using it in production.

To the extent the law allows, we are not liable for indirect damages, lost profits or data loss, and our total liability for any claim is limited to what you paid us in the 12 months before the event that gave rise to it.

9. Termination

You can stop using Lemma whenever you like. We may end the service for a customer who breaches these terms seriously or repeatedly, after telling them and giving them a chance to export their content, unless the law or other customers' security prevents it.

10. Changes to these terms

If we change these terms materially, we will tell you by email or in the console at least 30 days in advance. Continuing to use the service after that date means you accept the new version.

11. Governing law and contact

These terms are governed by the laws of Mexico. The parties submit any dispute to the competent courts of Guadalajara, Jalisco, without prejudice to the rights the Federal Consumer Protection Law gives you if you contract as a consumer.

Contact: juan.carlos@nxus.studio · Juan Carlos Díaz Mendoza · Guadalajara, Jalisco, México.