The ultimate zero-config local observability proxy for the Model Context Protocol. Intercept, replay, and share payloads in seconds across any language workspace.
Terminal
$ npx mcp-spy
Guided setup opens in your terminal. No flags needed.
Need more out of MCP-SPY? Cloud sync, web dashboard, token analytics, shareable traces and replay.
Need more details?
Read our extensive documentation on how to setup the Model Context Protocol proxy, connect to language servers, and utilize the CLI/TUI interface.
The local TUI is always free. Pro adds the web layer on top.
Pro Web Access
Everything the TUI can't do.
The local TUI shows you what's happening. Pro lets you act on it — from anywhere, with your team.
✓Web Dashboard — browse, filter and inspect every call in a full GUI, no terminal needed
✓Cloud Sync — every intercepted request is saved automatically as it happens
✓Shareable Traces — send a permanent link to any call, not a screenshot
✓Edit & Replay — modify any request in the browser and re-fire it without touching Claude
✓Token Analytics — see which tool calls are eating your context window, with cost estimates per model
✓Auto-Redaction & Mock Mode — strip secrets before storage, replay saved responses in CI
$12.50/mo
Billed annually
or $15 billed monthly
Just want the local TUI? It's always free.
No account. No config. One command.
npx mcp-spy -t 3001
What's shipped & what's next
Cloud Sync & Real-time Dashboard
Shipped
Every intercepted request syncs to your personal dashboard in real time. Filter by server, inspect payloads with syntax highlighting, and share any trace via a permanent public link.
Edit & Replay
Shipped
Modify any captured request payload directly in the browser and replay it against your local MCP server instantly — without re-triggering Claude.
Token Profiling & Cost Estimation
Shipped
Every log is automatically profiled for token count. See which tool calls are consuming the most context window and get rough cost estimates per method in the dashboard.
Auto-Redaction, Mock Mode & CI Runner
Shipped
Strip secrets automatically before they hit storage (--redact-pii), return saved responses without touching the real server (--mock), and run regression tests in GitHub Actions (mcp-spy test).
Session Timeline View
Coming Q2 2026
Group all tool calls from a single Claude conversation into a chronological timeline. See the full context of what the AI was doing — not just individual payloads in isolation.
Schema Diffing & Error Alerts
Coming Q3 2026
Automatic alerts when your server breaks its own JSON Schema response format. Webhook or email notification when any tool call returns a 5xx — before your users notice.