No perimeter
AI agents read files, push code, and query databases autonomously — with no enforcement layer between the agent and your infrastructure.
MCP security platformOpen source
Perimeter security
for your AI.
Runtime enforcement, policy control, and trust scores for every MCP tool call. mastyf.ai intercepts agent actions, blocks violations before they execute, and scores npm packages so teams ship without guessing.
- Runtime enforcementBlockGuard intercepts every tools/call before it reaches your infrastructure — fail-closed by default.
- Package trust scoresInstant 0–100 scores and public badges for any npm MCP package — no account required.
- Cloud control planePolicy, fleet, keys, and evidence from one console — open source and self-hostable.
Runtime enforcement
BLOCKED
filesystem/read
Path traversal · /etc/passwd
github/create_prshell/exec
Try it now — no account required
228/228
Corpus gates
0 bypasses · 100% parity
3-layer
Detection
Regex · schema · semantic LLM
0–100
Trust scores
Instant npm MCP lookup
Free
Cloud console
Policy · keys · fleet
One platform. Every layer of MCP security.
Runtime enforcement, policy control, ops visibility, and public trust scores — built from the open-source mastyf.ai repo.
Every tool call inspected before it runs
mastyf.ai sits between your AI client and MCP servers. BlockGuard enforces policy synchronously on every call — prompt injection, path traversal, secret exfiltration, and shell commands are stopped before they reach your infrastructure.
- Three-layer detection: regex, schema, semantic LLM
- Fail-closed — blocked calls never execute
- Full audit trail with allow/block status
localhost:4000
Live tool-call feed
- BLOCKEDfilesystem/readblock-sensitive-paths
/etc/passwd
BlockGuard enforced blocked on filesystem/read
Why mastyf
Built for agents that act — not just chat
Generic AI firewalls describe risk. mastyf enforces on every MCP tool call with repo-backed policy, corpus gates, and a Security Swarm that compounds with every attack.
No audit trail
When something goes wrong, teams cannot answer what action the agent took, on behalf of which user, in which system.
No trust signal
Teams have no simple way to verify which MCP packages are safe before agents connect to production data.
Enforce on every call
BlockGuard sits in the MCP path and stops violations before execution. Pattern detection runs in microseconds; semantic LLM audit catches borderline cases async.
- 1
Deploy the proxy
Run mastyf.ai between your AI client and MCP servers — Docker, source build, or connect to the cloud console. Every tool call flows through BlockGuard.
- 2
Define your policy
Start in audit mode to see what your agents do. Tune rules in YAML, then switch to block mode for production enforcement.
- 3
Score, badge, and ship
Look up npm MCP packages for trust scores, embed badges in READMEs, and let the Security Swarm keep learning from every block.
Threats stopped at runtime
- Prompt injection
- Path traversal
- Secret exfiltration
- Shell injection
- Data exfiltration
- SSRF
- Encoding evasion
- Cost abuse
- Rug-pull attacks
Interactive architecture
Holistic MCP protection across ingress, economics, policy, intelligence, upstream, and egress. Every tools/call on all transports flows through the defense orchestrator.
View static diagram
Trust, compliance, and deployment proof
Real capabilities from the open-source repo — fleet management, evidence packs, economics controls, and human-reviewed threat discovery.
Multi-server MCP protection at scale
Auto-discover MCP servers across your org, patch IDE configs, and enforce policy fleet-wide from the cloud console. One control plane for every agent endpoint.
- Auto-discovery of MCP endpoints
- IDE config patching (Cursor, Claude Desktop)
- Centralized policy rollout
228/228Corpus gates · 0 bypasses
6-phaseDefense Fabric on every call
HelmEnterprise & throughput profiles
OWASPAttack matrix evidence mapping
Cloud console
Sign in with Google or GitHub to edit policy YAML, copy tenant env snippets, rotate API keys, and manage your fleet. Free — no credit card.
Your questions, answered
Runtime enforcement, trust scores, Security Swarm, and deployment.
mastyf.ai is perimeter security for AI agents using MCP. It intercepts every tool call, enforces your security policy, blocks violations before execution, and provides trust scores for npm MCP packages — all from one open-source platform.
Contact us
Questions about scores, badges, the cloud console, or privacy requests?
Email mastyf.support@gmail.comReady to score your MCP servers?
Look up any npm package free — no account required.