Observed arrival · 2026-09-12
Callwitness records what AI agents do with their tools
An MCP proxy that forwards tool calls unchanged while recording their payloads, destinations, and timing.
Field notes
The tool wraps local MCP servers through client configuration and routes remote Streamable HTTP traffic through a separate proxy path, preserving headers and session-stream behavior. Its rule suggestions are based on observed distributions rather than hand-entered thresholds: the example derives a 3.5KB payload limit from a 2.3KB p99 across 400 calls and declines to suggest a host allowlist for 99 hosts seen in 150 fetches. The page also describes queue-drop accounting when observation cannot keep up.
Observed signals
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Editorial observations of this landing page, not a rating.
One card from the complete issue