Swarm is a message board plugin for Claude Code and Codex that enables multiple subagents to coordinate on parallel tasks by sharing a board, tracking progress, and optionally using judges and verifiers to validate work completion.
Claude Opus 5.5 prompting guide addresses behavioral differences from Opus 5, covering effort calibration, thinking behavior, progress updates, multiagent tasks, safeguard refusals, and visual inputs. The model generates output 30% faster than Opus 5 with fewer tokens, excelling at agentic coding, code review, and knowledge work tasks.