BYOK AI Code Review: Bring Your Own API Keys, Skip Per-Seat Pricing

What "bring your own key" means for AI code review

BYOK — bring your own key — means the AI code review tool runs on yourAPI keys instead of reselling model access to you. You create a key with OpenAI, Anthropic, or Google, connect it to the review tool, and every review is billed by your AI provider at the provider's own rates. The tool orchestrates the review; the inference bill goes straight to you, with no middleman markup.

That one architectural choice changes three things at once:

• Cost transparency.Your provider dashboard shows exactly what every review cost in tokens. There is no bundled "credits" abstraction hiding the real price of a review.
• Model choice. You are not locked to whatever model the vendor decided to run this quarter. New model ships? Point your routing rules at it the same day.
• Negotiated rates carry over. If your org already has enterprise pricing or committed-use discounts with a provider, your code reviews inherit them automatically.

The per-seat problem

Most hosted AI code review tools price per developer per month. That model is simple to buy, but it breaks down fast in practice, because review cost has almost nothing to do with headcount:

• Occasional contributors cost the same as heavy ones. The designer who opens two PRs a month occupies a full seat, priced identically to the platform engineer shipping daily.
• Seats scale linearly, value doesn't. At 50 engineers, the gap between a $20 and a $30 per-seat tool is $6,000 a year — before anyone has looked at whether the reviews are any good.
• You pay per person, not per review. A quiet month costs the same as a launch month. There is no way to spend less by reviewing less.

The alternative that's winning in 2026 is a flat platform fee metered by usage, with inference billed at cost through your own keys. That is exactly how PURA prices: a flat fee per plan, metered by reviews — no per-seat charges, and no markup on model usage. Whether you have 5 engineers or 500, the platform fee is the same, and the AI bill tracks what you actually reviewed.

Rule of thumb: if your team is bigger than a handful of people, or your PR volume is spiky, per-seat pricing means you are subsidizing someone else's usage. BYOK plus a flat platform fee means you pay for what runs.

BYOK without budgets is only half the fix

Here is the part most BYOK tools skip: once reviews run on your key, runaway usage lands on yourinvoice. An enthusiastic team pointing a premium model at every Dependabot bump can burn a month's inference budget in a week. BYOK gives you the steering wheel; you still need brakes.

PURA pairs BYOK with two control layers:

• Smart model routing. Plain-English rules in a .pura/PURA.md file decide which model reviews which PR — premium models for auth and payment paths, lean models for docs and dependency bumps. See the routing documentation for the full syntax.
• Fine-grained budgets. Daily, weekly, and monthly caps per developer, per repository, per team, and per provider and model. When a cap is reached, PURA pauses reviews instead of overspending.

The combination is what makes BYOK safe at scale: your keys, your provider rates, and hard ceilings on what any person, repo, or model can spend.

What about your keys themselves?

Handing an API key to a third-party tool is a trust decision, so it is worth asking every vendor the same questions. For PURA the answers are:

• Keys are encrypted at rest and never displayed again after you save them.
• Your source code is processed transiently to produce a review and not retained afterward — and it is never used to train models.
• Detected secrets are redacted before anything is sent to a model provider.

Setting up BYOK code review in five minutes

1. Install the PURA GitHub App on the repositories you want reviewed.
2. Connect your OpenAI, Anthropic, or Google (Gemini) API key in the PURA dashboard.
3. Optionally add routing rules and budgets — or start with the defaults.
4. Comment /pura review on any pull request. PURA posts one clear review: a summary, findings ranked by severity, and ready-to-apply fixes.

From that point on, every review runs on your keys, at your provider's rates, inside the budgets you set. The getting-started guide walks through each step in detail.

The bottom line

Per-seat pricing made sense when code review tools were seats of software. AI code review is metered compute, and pricing should follow the compute: a flat fee for the platform, inference at cost on your own keys, and budgets that keep the whole thing predictable. That is the model PURA is built on — and it is why teams switching from per-seat tools usually cut their review bill without cutting review depth.