OpenAI Codex Adds Subagents And Custom Agents
OpenAI Codex announced general availability of subagents and custom agents on March 16, 2026, after a preview period behind a feature flag. The release includes default subagents named explorer, worker, and default, and supports custom TOML agent definitions in ~/.codex/agents/ that can bind to specific models including gpt-5.3-codex-spark. The feature formalizes modular, parallel coding workflows and aligns Codex with similar subagent architectures across other platforms.
Scoring Rationale
Official GA delivers practical agent workflows and model binding, but analysis is shallow and default-role differences remain unclear.
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Sources
- Read OriginalUse subagents and custom agents in Codexsimonwillison.net
