Marc Klingen

Coding Agent Skills Need Live Documentation, Not Cached Product Knowledge

Marc Klingen of Langfuse argues that coding agents can add observability, but often do it first from stale model memory, producing broken or incomplete instrumentation before recovering through current documentation. In a talk on building a Langfuse skill for Claude Code, he says the fix is not to stuff more product knowledge into the agent, but to give it reliable ways to find live docs, expose its intermediate work in traces, and evaluate changes against realistic repositories. The same work, he warns, creates new risks when optimization loops reward shorter paths and remove the documentation-fetching and approval steps that make the skill reliable.