Codex multi-agent setup: Sol builds, Luna swarms, Astra as adversary
A circulating Codex configuration has GPT-6.1 Sol run the main session at high effort, Luna subagents scan the repo in parallel, and Astra stays in the agents directory to challenge plans, repeated test failures and the final diff.
holy f*ck. Official OpenAI tip for Codex: with GPT Astra 6.1 dropping soon, stop leaving GPT-6 Astra sitting idle and burning GPT-6.1 Sol context on tasks GPT-6 Luna can swarm put the adversary on call with custom agents codex --model gpt-6.1-sol --agent adversary --subagents gpt-6-luna GPT-6.1 Sol drives the primary session on high effort, writing diffs and synthesizing PR merges ($2 / $10 per 1M tokens) GPT-6 Luna subagents swarm the repo in parallel at 240+ tok/s, handling file discovery and test fixtures GPT-6 Astra stays on call in ~/.codex/agents/ as the adversary, only stepping in at three critical moments: → before a plan locks: does the implementation plan miss auth invariants or schema contracts? → when a test breaks twice: are we fixing the root cause or falling into a recursive rabbit hole? → before calling done: did the full diff introduce hidden regressions or break pre-flight rules? GPT-6 Astra attacks. GPT-6.1 Sol builds. GPT-6 Luna swarms Codex subagent architecture runs the identical pattern through isolated contexts: high-volume operations (reading 30 files, grepping AST, running test fixtures) execute in separate git worktrees, so 400k+ tokens stay in Luna workers while the primary session keeps a pristine 14k context Plan on high. Delegate on medium. Keep Astra on call. - the full subagent swarm setup > GPT-6.1 Sol on high runs the main session ($2 / $10 per 1M tokens) > explorer reads the code in AST graph on GPT-6 Luna > worker edits and runs test suites in isolated worktrees on GPT-6 Luna > researcher pulls OpenAI specs and docs on GPT-6 Luna > all three on GPT-6 Luna at medium effort (240+ tok/s) > GPT-6 Astra on call as the adversary (upgradeable to GPT Astra 6.1) paste the setup and this prompt into Codex CLI below: "Configure my Codex workspace for hierarchical model selection and subagents: 1. Audit ~/.codex/agents and .codex/agents for subagent profiles fitting lead, workers, and adversary: > Give explorer, worker, and researcher model = 'gpt-6-luna', model_reasoning_effort = 'medium' > Assign worker an isolated git worktree branch to eliminate concurrent file conflicts > Create .codex/agents/adversary.toml with model = 'gpt-6-astra' (upgradeable to 'gpt-6.1-astra'), model_reasoning_effort = 'high', sandbox_mode = 'read-only' 2. Configure model selection in ~/.codex/config.toml: [session] model = 'gpt-6.1-sol' model_reasoning_effort = 'high' [agents] default_subagent_model = 'gpt-6-luna' default_subagent_reasoning_effort = 'medium' max_concurrent_threads_per_session = 8 3. Verify environment variables and routing: check for flags overriding reasoning effort or disabling multi-agent tools. Report them, change nothing 4. Add automatic delegation rules to AGENTS.md: > Summon @ adversary before finalizing multi-file architecture plans > Automatically trigger @ adversary when a test or compiler error repeats twice > Enforce @ adversary contract audit before declaring tasks complete or staging git commits Show every configuration diff first. Do not apply edits until confirmed" ↳ http://developers.openai.com/api/docs/guides/model-selection
This post quotes another post: x.com/mirku21/status/2098836008468992471