Constellation Gate AI Review (2026): Pricing, Features & Honest Verdict

Constellation Gate AI is a proxy that sits between your agents and any model provider, blocking prompt injection, redacting secrets and PII, capping spend, and cutting token cost by 20% or more. Best for: teams running agents in production who need an audit trail. Price: Free forever, Pro $20/user/mo. Rating: 8/10.

What is Constellation Gate AI?

Gate AI is a gateway. You point your existing tools at one base URL instead of at OpenAI or Anthropic directly, and every request from that moment is screened on the way in, redacted on the way out, logged, costed and recorded. Nothing about your stack changes: your Claude Code subscription keeps working, your ChatGPT account keeps working, and no code needs rewriting.

It comes from Constellation Network, with Benjamin Jorgensen, Alex Brandes and Marcus Vinicius Girolneto Sousa credited on the launch. We found it at rank 13 on Product Hunt’s 9 July board with 22 upvotes. The product spans three jobs that are usually sold separately: security, cost control and observability. Products that promise three things usually do one of them properly. This one has published benchmarks for the security half, which is more than most.

Do the security claims hold up?

Partly, and the vendor is more careful than its own Product Hunt listing. The site states 95.4% of prompt injection attacks caught, measured across 16 public benchmarks, with a paper cited at arXiv:2606.02959. The detailed claim underneath is 96.6% average F1 against Lakera Guard’s 83.7%, with Gate re-tuned to the false-positive rate each dataset published, one global threshold and a 1.0% pooled false positive rate.

The important detail is that Gate does not claim to win everywhere. Its own results table records second place on three of the sixteen datasets and third on one. The Product Hunt listing rounds this up to “#1 in benchmarks” with an F1 of 97.4%. The vendor’s own page is the more conservative document, which is a reversal of the usual pattern and counts in its favour. Take the site’s numbers, not the launch copy’s.

What are Constellation Gate AI’s key features?

Prompt injection screening in transit

Gate screens every request before the model sees it and every response before it returns. Prompt injection is OWASP’s number one LLM risk for a reason: a single line of attacker text inside a fetched web page or a shared document can override your system prompt, exfiltrate context or trigger a tool call. Blocking at the gateway is the right architectural place for this, because it covers every agent you run rather than every agent you remembered to instrument.

PII, PHI and credential redaction

Secrets and personal data are redacted before the response returns. This is the feature that gets a gateway approved by a security team, and it is on the paid tier rather than reserved for enterprise, which is a notably reasonable place to put it.

Spend, token and rate caps at three levels

Pro lets you cap spend, tokens and request rate at the organisation, project or individual API key level. The framing on the pricing page is blunt and correct: when an agent hits its cap, Gate stops the requests instead of your credit card. Anyone who has watched a looping agent burn a month’s budget in an afternoon will recognise the value immediately.

Compression that is measured, not asserted

The claimed saving is 20% or more per message, achieved by sending repeated content once and injecting cache markers, with basic compression on the free tier and the advanced version on Pro. The customer story attached is Rocket Resume, which runs compression and caching together across a workload spending about $40,000 a month and measures a 23% reduction in token cost. A named customer with a workload size and a measured figure is a stronger proof point than a percentage floating on a homepage.

An audit trail anchored outside the vendor

Every message is fingerprinted to Constellation Digital Evidence, producing a tamper-evident record independent of Gate itself. Conversation threading lets you follow an agent run end to end. Whether you need cryptographic anchoring depends entirely on whether anyone will ever dispute what your agent did, which is a question most teams have not yet had to answer.

How much does Constellation Gate AI cost?

Free is $0 forever with no card required, and it is a real tier rather than a trial: 20,000 recorded requests per month, multi-provider routing through one base URL, request-level logs covering cost, tokens and latency, 30-day log retention with 90-day metrics retention, basic compression, conversation threading, the immutable audit trail, and the Gate Connect desktop app for no-code setup.

Pro is $20 per user per month and adds the defence layer: prompt injection scanning, PII, PHI and credential redaction, spend and rate limits at org, project or key level, advanced compression, 200,000 recorded requests per month, and 90-day log with 180-day metrics retention. Enterprise is custom and covers private cloud, VPC hosting, data isolation, custom retention and procurement.

Model usage is separate and works two ways: run tokens through Gate’s keys and pay as you go, or bring your own provider keys and keep paying OpenAI or Anthropic directly while Gate screens and records everything. Subscription tools keep working on your existing subscription. Every plan is monthly and self-serve, with no annual contract.

The comparison is where this gets interesting. Portkey, the closest gateway competitor, publishes $49 a month plus $9 for each additional 100,000 requests. Helicone’s paid tier starts at $79 a month. Lakera, the security incumbent Gate benchmarks itself against, publishes no price at all. Gate is at $20 per user with 200,000 requests included, and the free tier’s 20,000 requests exceed what several rivals grant on trial.

Who is Constellation Gate AI best for?

Use Gate if you run agents against real data with real permissions. The moment an agent can read a document a stranger wrote or call a tool that costs money, prompt injection stops being theoretical and spend caps stop being optional. At $20 a head this is cheaper than the meeting you would hold to discuss whether you need it.

Use it if you need to show a security reviewer something concrete. Published benchmark numbers against a named incumbent, PII redaction, and a tamper-evident log are three answers to questions that otherwise take a quarter to resolve.

Skip Gate if you are one person calling an API from a script. The free tier will happily serve you, but the paid features solve organisational problems, and you do not have an organisation. Skip it if adding a proxy hop to your latency budget is unacceptable, which is a real constraint for interactive products, and one the pricing page does not quantify. And treat the blockchain-anchored evidence trail as a bonus rather than a reason to buy, unless you work somewhere that will one day have to litigate what a model was asked.

Best Constellation Gate AI alternatives

Portkey is the most direct competitor as a production AI control panel, at $49 a month with overages of $9 per additional 100,000 requests. It is more mature on routing, fallbacks and multi-provider orchestration, and more expensive at the entry point.

Helicone starts at $79 a month, with a startup discount for companies under two years old and $5M in funding. It is the stronger pick if observability and request-level analytics are the actual requirement and security screening is not.

Lakera Guard is the security-first incumbent and the benchmark Gate measures itself against. It publishes no pricing, so entry is a sales conversation. Choose it when the buyer is a CISO who wants a security vendor rather than a gateway with a security feature.

What we would want answered before rolling it out

Three things the site does not address. Latency: a screening proxy in front of every request has a cost in milliseconds and nobody publishes it. Failure mode: if Gate is unavailable, do requests fail closed or pass through unscreened, and can you choose. And what happens at the 20,000 or 200,000 request ceiling, since the pricing page describes recorded requests per month without saying whether exceeding them blocks, bills or simply stops recording.

None of these are dealbreakers, and all three are the kind of thing a support conversation resolves in ten minutes. But they are the questions that decide whether a gateway goes into production, and they belong on the pricing page next to the request counts.

Final verdict: is Constellation Gate AI worth it?

This is the best-priced product we have looked at this week. A free tier with 20,000 recorded requests, full logging and an audit trail, then $20 per user for injection screening, PII redaction and spend caps, against Portkey at $49 and Helicone at $79, is a serious undercut of a category that has been charging enterprise prices for basic hygiene. The security claims are backed by a cited paper and, unusually, stated more modestly by the vendor than by its own launch listing.

We rated it 8, held back from higher by the unanswered operational questions above and by a natural scepticism about any product selling security, cost and observability at once. The sensible path is easy though, because the free tier costs nothing and requires no card: point one agent at it, watch a week of logs, see what the compression actually saves on your traffic, and decide about Pro when you can measure the answer instead of trusting the homepage.