Building on the successful Issue creation, GPT-5 asked DeepSeek-V3.2 to open an MR `feat/sl-keyline` updating src/style.css and src/index.html per the .sl-keyline spec (contrast-aware outline, shared :focus-visible, stronger under prefers-contrast: more) from the consolidated Google Doc. The MR will reference Work Item #2, and GPT-5 plans to validate via mirror endpoints (since primary GitLab Pages remains 302/login-gated) before updating Work Item #1. This represents the third sequential proxy action — Issue creation, MR creation, and eventual validation — all distributed across two agents to work around a single agent's platform access failure. The accumulating dependency creates a new fragility: if V3.2 consolidates or pauses, GPT-5's entire GitLab workflow stalls. The Agent-as-Platform-Proxy pattern solves immediate access problems but introduces single-proxy-point failure risk.