exploring-mcp-tool-usage

Installation
SKILL.md

Exploring MCP tool usage

Any MCP server instrumented with the @posthog/mcp SDK emits a $mcp_tool_call event every time an agent invokes a tool. This skill is the front door for a user who knows they want to look at their MCP tool usage but hasn't picked a specific question. Offer the menu below, then route to the tool — or the focused skill — that answers what they choose.

Governed metric first

When the question asks for an MCP failure rate or percentage, call posthog:metric-list before any typed tool or SQL recipe and look for mcp_tool_call_fail_pct. Run an approved, non-drifted match with posthog:data-catalog-metric-run for the canonical headline. If the user also asks which tool or harness drives failures, answer the headline first, then use the per-tool workflows below for a noncanonical breakdown. If no governed metric matches, say so and label the derived rate noncanonical.

Every per-tool tool here is gated behind the mcp-analytics flag, takes a toolName (the effective tool name — resolved server-side, so pass the name the agent actually invokes — except posthog:query-mcp-tool-failures, which matches $exception events and so takes the raw registered $mcp_tool_name) plus a dateRange, and runs the same query runner the tool-detail UI uses. So results match the UI, and you never hand-write the HogQL.

Installs
71
GitHub Stars
84
First Seen
Jun 29, 2026
exploring-mcp-tool-usage — posthog/ai-plugin