RelayPlane vs AISIX (API7.ai)

AISIX is an AI-native API gateway announced by API7.ai in April 2026. RelayPlane is an in-process cost and control layer that installs via npm with no cloud deployment required. Here is how they compare for AI agent builders.

TL;DR

Choose RelayPlane when you want:

  • npm install with zero cloud dependency
  • Session-level budget caps and kill switches
  • Agent-loop detection (repetition detector, token explosion guard)
  • In-process control with 0ms network overhead
  • Local-first: no data leaves your machine by default

AISIX may work for you if you need:

  • Network-layer API gateway for multi-team or multi-service routing
  • Cloud-managed gateway infrastructure from API7.ai
  • Enterprise gateway features: rate limiting, auth, multi-provider routing

Feature Comparison

FeatureRelayPlaneAISIX (API7.ai)
Deployment model

RelayPlane runs in-process with zero network hops. AISIX is a cloud-deployed gateway: all requests route through API7.ai infrastructure before reaching your LLM provider.

In-process, runs alongside your agent on localhostCloud-deployed AI-native API gateway (network layer)
npm install

RelayPlane ships as a single npm package: npm install -g @relayplane/proxy. AISIX requires deploying an API gateway service, no npm package.

Local-first / zero cloud dependency

RelayPlane stores logs in local SQLite. No data leaves your machine by default. AISIX is cloud-deployed, all traffic routes through API7.ai infrastructure.

Latency overhead

Because RelayPlane runs in-process, it adds zero network latency. AISIX introduces gateway round-trip latency on every LLM request.

0ms network overhead (in-process)cloud network round-trip latency added per request
Session-level budget caps / kill switches

RelayPlane enforces per-session budget caps with real-time kill switches that halt a runaway agent mid-loop. AISIX provides gateway-level policy enforcement but lacks session-scoped cost intervention.

Agent-loop detection

RelayPlane includes a repetition detector and token explosion guard that fires when an agent enters a loop. AISIX focuses on request routing and gateway policy, not agent behavioral anomalies.

No account required

RelayPlane starts with no signup, no API key, no cloud dependency. AISIX requires deploying and configuring a gateway service with an API7.ai account.

Open source / self-host

RelayPlane is MIT-licensed and fully self-hosted by default. AISIX is a managed cloud gateway product from API7.ai.

Real-time spend intervention

RelayPlane can kill an agent session the moment it exceeds a budget threshold, before the next LLM call is made. AISIX enforces policies at the gateway but does not provide in-process session termination.

Cost reduction via smart routing

RelayPlane routes requests based on task complexity, sending simple tasks to cheaper models and reserving expensive models for complex work. This produced a 73.4% cost reduction on measured usage. AISIX focuses on gateway-level routing and policy enforcement without a model cost optimization layer.

73.4% measured cost reduction via complexity-based routingCloud gateway routing (no task-complexity cost optimization)
LLM provider routingLocal intelligent routing with cost awarenessCloud gateway routing across LLM providers

Why AI Agent Builders Choose RelayPlane Over AISIX

1.

In-process vs network-layer: a fundamental architectural difference

AISIX (announced by API7.ai on 2026-04-24) is an AI-native API gateway, a cloud-deployed network proxy that routes traffic between your agents and LLM providers. RelayPlane is not a network proxy. It runs in-process alongside your agent, which means zero added network latency, zero data egress by default, and the ability to intercept and terminate a session before the next API call fires. These are complementary shapes: AISIX governs at the network boundary; RelayPlane governs inside the process.

2.

npm install vs gateway deployment

RelayPlane installs with a single npm command and starts proxying in under 30 seconds. No cloud account, no gateway deployment, no infrastructure to manage. AISIX requires deploying and configuring an API gateway service. For individual developers and small agent teams who want cost visibility and kill switches today, the friction difference is significant.

3.

Session-level budget caps and kill switches

RelayPlane enforces per-session spend limits with real-time kill switches: if an agent loop burns past its budget, RelayPlane halts it before the next LLM call is made. This is possible because RelayPlane runs in-process. A network-layer gateway like AISIX can enforce request-level policies, but cannot terminate a running agent session from inside the process boundary.

4.

Agent-loop detection built in

RelayPlane ships a repetition detector and token explosion guard. When an agent starts looping, repeating the same prompt pattern or exploding token counts, RelayPlane fires before the bill compounds. AISIX focuses on LLM routing and gateway policy enforcement; behavioral anomaly detection inside the agent loop is not its design surface.

5.

73.4% cost reduction via complexity-based routing

RelayPlane routes requests by task complexity: simple prompts go to cheaper models, hard problems go to expensive ones. On measured usage, this produced a 73.4% reduction in LLM spend with no change to output quality. AISIX is a gateway that routes for availability and policy compliance. It has no task-complexity cost optimization layer and no per-request cost tracking built in.

AISIX and RelayPlane are complementary, not zero-sum

AISIX (announced by API7.ai on 2026-04-24) targets the network-layer API gateway space for LLMs and AI agents, managing routing, authentication, rate limiting, and policy enforcement at the infrastructure boundary. This is genuinely useful for platform teams running multi-service agent architectures.

RelayPlane targets a different layer: the in-process cost and control surface inside an individual agent process. If you are building an agent that needs real-time budget caps, agent-loop detection, and zero-latency cost tracking, without deploying a cloud gateway, RelayPlane is the fit. The two tools can coexist: AISIX at the network boundary, RelayPlane inside the process.

Get Running in 30 Seconds

No account. No cloud. No gateway deployment:

# Install globally
npm install -g @relayplane/proxy
# Start the proxy
relayplane init
relayplane start
# Point your agent at localhost
// OPENAI_BASE_URL=http://localhost:4100

Start controlling LLM costs in one command

No account. No monthly fee. MIT open source. In-process with Claude Code and Cursor in under 30 seconds.

npm install -g @relayplane/proxy