Portkey alternative
A Portkey alternative — for when the runaway hits Stripe, not OpenAI
Portkey is an AI gateway for LLM traffic — virtual keys, budget caps, fallback routing, observability. If the incident you're trying to prevent involves dollars on Stripe, SMS on Twilio, or emails on Resend, Portkey's governance layer can't see that traffic. Keybrake can. Here's when switching away from Portkey is the wrong move, and when adding Keybrake alongside it is the right one.
TL;DR
Keybrake is not a drop-in Portkey alternative for your LLM traffic. Portkey is strong at what it does: virtual keys, per-key budgets, 200+ LLM integrations, and a managed observability dashboard. What Portkey doesn't do is govern the non-LLM SaaS APIs your agent also calls — Stripe charges, Twilio SMS, Resend emails. Keybrake is the governance layer for that second half. If you're happy with Portkey for LLM traffic, keep it. If you also need spend caps, endpoint allowlists, and mid-run revoke on SaaS APIs, add Keybrake beside it. That's the dual-proxy pattern most 2026 teams actually ship.
What Portkey is and isn't
Portkey (portkey.ai, Y Combinator S23) sells itself as "the control panel for AI agents". In practice it's an AI gateway with three main surfaces:
- Virtual keys and budgets — you mint a short-lived key bound to an underlying OpenAI/Anthropic/Google key, attach a spend cap, and hand the virtual key to a team or an application.
- Routing and fallbacks — declarative rules for "try GPT-4o, fall back to Claude on 429, fall back to Gemini if that also fails".
- Observability — a dashboard with request-by-request logs, per-key cost charts, latency histograms.
All three features operate on one kind of traffic: LLM inference calls to model providers with OpenAI-compatible schemas. That is the same category LiteLLM, Helicone, and OpenRouter play in. It is not the category Stripe or Twilio lives in.
Why "Portkey alternative" is often the wrong search
Most "Portkey alternative" searchers land there for one of three reasons: pricing at scale, self-hostability (Portkey's control plane is managed SaaS), or feature gaps on a specific LLM integration. For those shoppers, our five-option open-source review is a better destination — Portkey vs LiteLLM vs Helicone vs OpenRouter vs Bifrost is a real comparison inside one category.
A smaller but growing slice of "Portkey alternative" searchers arrives after an incident on a non-LLM API. Their agent ran a Stripe refund loop and burned $4,000 of fees in twenty minutes. They assumed Portkey's budget cap would have caught it; they were surprised it didn't. Those people are not looking for an alternative to Portkey — Portkey did exactly what it was designed to do, which is govern LLM spend. What they're looking for is the other half of the stack.
Keybrake vs Portkey: what each actually governs
| Concern | Portkey | Keybrake |
|---|---|---|
| "Cap what the agent spends on GPT-4 per day" | Yes, first-class | N/A (not an LLM gateway) |
| "Cap what the agent spends on Stripe per day" | No — Stripe traffic doesn't flow through Portkey | Yes, first-class (parsed from Stripe response) |
| "Cap what the agent spends on Twilio per day" | No | Yes (parsed from Twilio's price field) |
| "Restrict which OpenAI models the agent can call" | Yes, model allowlist per virtual key | N/A |
| "Restrict which Stripe endpoints the agent can call" | No | Yes (e.g. block /v1/payouts, allow /v1/charges) |
| "Block the agent from charging customers outside a whitelist" | No | Yes (Stripe customer-ID allowlist, Connect account allowlist) |
| "Revoke the key mid-run without rotating the upstream secret" | Yes (for LLM keys) | Yes (for SaaS vendor keys) |
| "Audit: which customer did the agent charge under which run?" | N/A | Yes — audit row per call with parsed cost, endpoint, params, policy result |
When Keybrake actually replaces Portkey
There's a narrow but real case: your agent runs downstream of a managed workflow that already handles LLM inference (Temporal activity, Inngest function, a workflow in Lovable / Replit Agent / Cursor's agent mode). The workflow doesn't need an LLM gateway — it's a thin layer between a coding assistant and the actual tool calls. In that case you might skip Portkey entirely and put Keybrake in front of the tool calls. Stripe, Twilio, Resend is where the money moves; that's what needs the proxy.
For any agent that directly hits LLMs, Keybrake does not replace Portkey. It supplements it.
When Portkey is still the right answer
- You need an LLM router. "Try this model, fall back to that model, enforce a timeout, log it all centrally." Portkey's routing DSL and 200+ model integrations are hard to match. Keep it.
- Your agent doesn't touch money-moving APIs. If the outbound traffic is all LLM + read-only data APIs, adding Keybrake gives you nothing.
- You need prompt caching and semantic caching. That's Portkey's (and Helicone's) specialty; Keybrake does not cache anything because SaaS calls are usually mutating.
Running both: the dual-proxy pattern
Engineering teams running agents against both LLMs and SaaS tools in production typically ship two proxies. The agent holds two kinds of token: a Portkey virtual key for LLM traffic, a Keybrake vault key for SaaS-tool traffic. An x-agent-run-id header flows through both; the audit trails join on that column to give you a per-run spend breakdown. Neither proxy is aware of the other. Both cap their own blast radius.
agent
├─ base_url=https://api.portkey.ai/v1 (virtual key pk_v_…) → OpenAI / Anthropic / Gemini
└─ base_url=https://proxy.keybrake.com (vault key vault_…) → Stripe / Twilio / ResendBoth calls carry x-agent-run-id: run_abc. Post-hoc, a three-line SQL against both logs tells you: for run run_abc, the agent spent $3.14 on GPT-4 tokens (Portkey) and $247.00 on Stripe charges (Keybrake). That's the number finance actually wants.
Concrete next step
If you already use Portkey, adding Keybrake is not a migration. In the code path where your agent calls api.stripe.com, swap the base URL to proxy.keybrake.com/stripe and replace the Stripe secret with a Keybrake vault key. Attach a policy with a daily USD cap (start at $100/day, adjust up once you've seen a week of normal traffic). Done.
Further reading
- Portkey vs Keybrake (side-by-side) — same compare, table-first for fast readers.
- LiteLLM alternative for Stripe — the technical explainer on why LLM gateways can't broker SaaS APIs.
- AI agent kill-switches — measured stop-latency per vendor (Stripe, Twilio, Resend, OpenAI).
- Stripe API keys with restricted access — 10-control matrix — what Stripe's native feature does and doesn't cover.
Try Keybrake
If you run agents that touch Stripe, Twilio, or Resend in production, the proxy takes five minutes to drop in and the free tier covers 1,000 requests/month.