The task() tool schema declares run_in_background as a REQUIRED parameter, but three prompt-template files contained category-based task() examples that omitted it. When agents copied these patterns into actual tool calls, the runtime validator threw 'run_in_background parameter is REQUIRED', breaking delegation.
Add run_in_background=false to the four offending category-based examples: 2 in src/agents/dynamic-agent-category-skills-guide.ts (Delegation Pattern + Category Domain Matching CORRECT/WRONG pair), 1 in src/agents/hephaestus/gpt-5-3-codex.ts (frontend example), and 1 in src/agents/sisyphus/gemini.ts (Example 4 DELEGATE). Subagent-type explore/librarian examples already correctly use run_in_background=true. atlas/shared-prompt.ts examples were already correct.
Verification: bun test src/agents/ — 373 pass, 0 fail. bun run typecheck — clean. Grep confirms no remaining category task() examples lack the parameter.
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