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Liminal MCP · for businesses and builders

Bring Liminal's reasoning into the tools your team already uses.

Liminal MCP is the shared intelligence workspace behind the Liminal app, served over the Model Context Protocol. Add one remote server to Claude, Cursor, or your own agent and every hard question gets broken down, grounded, and answered with its reasoning attached.

Get a free key Read the setup documentation

Email and a password. The key is issued immediately. The first 50 solves on a new key are free; no card required.

Connect your client

Create an account, add Liminal to your client, and ask a question. The documentation includes setup instructions for each client.

The hosted endpoint is https://liminality.physea.ai/mcp. Your client sends your key in the X-API-Key header; the setup documentation shows how.

Open the setup documentation

Need to check your connection? Read the troubleshooting steps.

What your agent gets

The same engine as the app, with tools for research, evidence, and saved work.

Tool list

22 tools, one front door.

solve takes a question, a decision, or a multi-step task and returns a checked result with its steps. The rest are for control and reuse: research for a multi-source pass, handoff and delegation for cross-session work, compress_context to turn a long transcript into a brief, export_result and get_result_detail to pull the full record, composio_connect to attach a tool your agent may write to, and report_outcome and report_feedback to tell the route how it held up.

Add the server →

Sources

Answers come back with evidence records, not just prose.

Each retrieved source is stored as an evidence record with a hash and the excerpts the answer relied on. Your agent can quote them, and a person can open them. If the request requires evidence and none supports a claim, the grounding validator fails closed and the result is returned as an uncertified candidate rather than a solved answer.

How this looks in the app →

Honest states

Blocked is a state your agent can read.

A step that needs a connection your agent has not given is returned as "needs a connection" with a connect link; it is never fired without your go-ahead. A step that could not run is "not run" with the reason. A result that failed certification is returned with status FAIL, state candidate, and the list of unsupported claim IDs, so your agent can decide whether to retry, ask you, or stop.

See the same state in the app →

Handoffs and delegation

Checkpoint in one session, resume in another.

A handoff stores the objective, work so far, evidence, and acceptance criteria. Resume with its saved ID to reopen the exact work you meant. If you ask for the latest checkpoint and several were created recently, Liminal asks which subject to continue. Delegation gives another agent a bounded task and brings back a report without silently merging its work.

Measured on three multi-session coding runs with real checkpoint and resume calls: acceptance 5 of 5 preserved, caller wall time 6% slower. The token and cost figures are being re-derived against a recorded model-only baseline before we print them. One run, our own bench.

Checkpoint rules and limits →

Receipts

Every result carries its IDs, its validators, and its cost.

The solve response includes result_id, request_id, the certification record with all eight validators, the grounding status, and the cost line. export_result returns the same record in a portable form. This is what lets a person audit what an agent did after the fact.

The receipt in the app →

Get a free key Read the setup documentation Open the Liminal app

50 free solves on every new key. No card.

Before you connect

Plain answers to the questions a security or platform review asks first. Full detail is in the Privacy Policy and Terms of Service.

Hosted

Liminal MCP is a hosted service at liminality.physea.ai, operated by Physea Labs from the United States. There is no self-hosted or on-premises version today. If your policy requires one, contact us before you connect.

What we receive

The question and any context your client sends with it, plus standard request metadata (IP address, client, timing). Each request is metered against your key.

Model providers

Requests are routed to approved model providers through Amazon Web Services. Providers receive the content needed to answer. We do not sell your data or use it for advertising.

Retention

Solve results are kept with your account so you can reuse them, and are deleted or de-identified within 30 days of a verified deletion request. Aggregated analytics may be kept up to 24 months.

Keys and access

One key per account, sent as a header over HTTPS only. Rotate or delete it from your account, or ask us and we revoke it. Never paste a key into a shared config repository.

Not yet

No SOC 2 or ISO 27001 report, no signed DPA or BAA, and no regional residency option. We say so rather than imply otherwise. Ask if one of these blocks your team.

What your client gets

Research

Multi-source retrieval with the sources kept, and a clear missing-evidence state when there is nothing solid to stand on.

Decomposition

A hard question becomes bounded sub-questions, each tied to a real source, then scored into one answer you keep.

Decisions

Frame a choice, score the options, and get a decision with its trade-offs visible.

Handoffs

Create and resume verified checkpoints across sessions, machines, and models.

Visible failures

Blocked, partial, and source-less results stay visible instead of being dressed up as success.

[See the full feature map →](https://physea.ai/features/)

Pricing

Start free. The first 50 solves on a new key cost nothing. They belong to the account that holds the key, not to a network address, and free solves used in the app before signing up carry over. After that, buy solves in packs that never expire or on a monthly plan. One solve is one question start to finish; the follow-up calls inside a solve (a follow-up question that names the earlier result, forms, grounding, execution, verdicts) are included and never billed again.

Free

50 solves on every new key. No card. Get a key.

Packs

$0.50 a solve, never expire. 20 solves for $10 · 100 for $50 · 1,000 for $500.

Monthly

$250 for 500 solves each month, with rollover. Go monthly.

Teams

Use the same email at checkout that you used for your key and the solves land on that key. A team can share one key today, or each person can hold their own free key. Need one invoice for many seats? Ask us.

Checkout is handled by Stripe. Your key is topped up automatically after payment and the receipt goes to the email you used. Unused solves are refundable within 30 days (see the Terms). Comparing options? See all Physea pricing. Questions? Contact us.

Prefer to try it in the browser first?

The Liminal app runs the same engine. Create a free account and your first 50 solves are free.

Open Liminal What Liminal is →

Not sure which door you need? Pick a starting point.

Contact

Talk to us

Tell us what you're building.

A real person answers, not a queue. Even if the answer is "not us, try this instead."

NameEmailWhat's on your mind?Send

Or head to our contact page. No list, no autoresponder.

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Liminality · free account

Solving takes a free account

Email and a password, that's the whole signup. You get a key on the spot and your first 50 solves cost nothing. If you typed a request, we carry it through and run it as soon as your key exists.

Create my free account →

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