{"method":["Protocols declared before the first call, one per route. Every attempt is kept; nothing was retried.","Caching: 9 sessions (3 × Claude Sonnet 5.5 · Claude Code, 3 × Claude Opus 5.5 · Claude Code and 3 × GPT-6.1 Sol (medium) · Codex CLI), 5 turns each. A session is one CLI process. Turn 1 sends a seeded synthetic stock ledger plus question 1; turns 2-5 send one short question each (lookups, a count, an arg-max), each with one exact answer. Each turn is one model request.","A 2-call probe sized the context before the run (not part of any cell). The ledger was larger than declared, so it was cut once, from 170 to 100 lines, and the answers were recomputed, as the protocol allowed.","The Codex sessions ran before that cut, on the 170-line ledger (16,197 characters vs 9,651). The two routes are reported side by side, never as a like-for-like pair.","Cache counters as the provider reports them: Claude Code gives uncached input, cache reads and cache writes (with the 5-minute and 1-hour split); the Codex app-server gives input (cached included) and cached input, and no cache writes.","Cost with and without the cache (Claude only): see the calculation source. Every write in this run was a 1-hour write, so the 5-minute multiplier (an assumption) was not used.","Consistency: 3 prompts (an exact number, a JSON object with exact keys, a small code fix), each with a deterministic validator; 10 repetitions per prompt for Claude Haiku 4.5 · Claude Code, Claude Sonnet 5.5 · Claude Code and GPT-6.1 Sol (medium) · Codex CLI. One-shot calls, one at a time per account. Answer diversity counts distinct normalized answers; the raw extract holds ordinal answer ids, never the text.","Validator controls ran before inference on each route: every reference answer passes, every plausible wrong answer fails, and a wrapped reference is flagged as a format miss.","Isolation as in the hard head-to-head: fresh empty working folder, tools off, no MCP servers, no session persistence across processes, provider-default caching. Claude at its default effort; GPT-6.1 Sol at medium.","No batch stopped early and nothing was trimmed. The Claude CLI reported a rate-limit status of \"allowed_warning\" on 7 of 30 cache turns; no call was refused and the run did not stop."]}