agent-creator

Authors Claude Code custom subagents (.claude/agents/<name>.md, ~/.claude/agents/<name>.md, or <plugin>/agents/<name>.md). Use whenever a new subagent is being designed, an existing agent is being edited, a tool allowlist or denylist is being chosen, a model and effort budget are being set, permissionMode is being picked, persistent memory (user/project/local) is being added, skills: are being preloaded into a subagent, isolation: worktree is being configured, the agent's system-prompt body is being structured (Identity/Execution/Output/Failures/Constraints), or an agent that fails to fire or returns the wrong shape is being debugged. Triggers on "create a custom subagent", "write a new agent", "add an .claude/agents/ file", "make a code-reviewer", "tool restrictions for an agent", "agent system prompt", "preload skills into an agent", "agent memory", "agent worktree", "fix this agent". Use even when the user does not say the word "agent" but is asking to delegate a recurring task to a fresh isolated context. Pair with ac:skill-creator for the surrounding file-shape and scope decisions, and with ac:prompt-writer for the system-prompt body content. Target is Opus 4.8; Sonnet 5 follows the same shape at lower effort. Undertriggering is the failure mode, lean in when the request implies an isolated worker.