The API client built for developer security.
Test APIs locally. Keep secrets in your own infrastructure. No account required to start. And when your team builds AI agents, KeyRunner is already the security runtime.
Free forever. No account required. Also available for Mac and Linux below.
Built for teams that care where secrets live
KeyRunner isn't just a request editor. It's an API execution environment with security controls built in from the start.
Runs entirely on your machine
No cloud required for core workflows. Requests execute locally, secrets stay in your infrastructure, and nothing is logged by default.
Vault & 1Password integration
Pull secrets from HashiCorp Vault, 1Password, or AWS Secrets Manager at request time. The secret never appears in your collection or history.
Response redaction
Define fields to redact from API responses, PII, PCI, PHI, before they appear in the UI, logs, or shared workspaces.
Mock servers
Define mock responses and simulate APIs without hitting production. Build and test against contracts before endpoints are ready.
Monitoring & observability
Track request latency, response codes, and usage patterns across your API collections. Built in, no third-party integration needed.
Zero telemetry by default
KeyRunner does not log requests, send usage data, or require account creation to start. Your API traffic is yours.
The same tool becomes your enterprise agent security runtime.
When your team starts building AI agents that call the same APIs you're testing today, KeyRunner is already the infrastructure. Register those APIs as governed actions. Agents call them with policy enforcement, runtime credential injection, and a full audit trail. The agent never sees the key.
Test APIs locally. Secrets stay in your infra. Works offline. No account.
Register those same APIs as governed, policy-controlled agent actions in KeyRunner.
Agents call actions. KeyRunner injects credentials, enforces policy, and audits every execution.
Start free. Grow into enterprise.
No account needed to download and start testing APIs today.