Validate a strategy/signal before you execute (sync)

Honest, look-ahead-aware backtest validation for agentic stacks. Send a named catalog strategy (type=rules), a timestamped BUY/SELL signal list (signal_list) or a timestamped trade list (trade_list). Returns an EVIDENCE verdict — 'insufficient_evidence' | 'anecdote' | 'failed_oos' | 'passed_oos' — plus metrics, flags and caveats. NOT a buy/sell recommendation. Checks: realistic next-bar fills (look-ahead / fill-optimism), net of cost, out-of-sample split, and a hard sample gate (under 30 round-trips is always 'anecdote'). Per-endpoint quota: Pro 50/d, Power 500/d. No strategy IP is stored. [API Pro tier]