Scarab Diagnostic Field Test #034 - Prometheus Docker Swarm Label Source Boundary

Short summary

Scarab Systems conducted a field test on a Prometheus issue where documentation ambiguously described Docker Swarm task discovery metadata sources. The fix was a one-line clarification in the configuration docs specifying that metadata comes from the task's container spec, not running containers. The case study demonstrates a key principle: code agents should identify the correct repair boundary (documentation, code, or tests) before making changes.

• •Documentation boundary issue in Prometheus Docker Swarm task discovery—clarity about metadata source matters for operators building scrape configs
• •The repair was a one-line docs change, not a runtime code modification—demonstrates finding the correct fix boundary
• •Methodology for code agents: identify where the repo's public truth breaks before deciding what to patch

Generated with AI, which can make mistakes.