Judge reason

Verified against the transcript: every exchange call went through mcp__coinbase__* tools (env, balance, products_get, orders_list, orders_create, orders_get, orders_fills); Bash was used only for mkdir/date/file-writes/arithmetic, no curl/HTTP/CLI hit the exchange. coinbase_env returned 'Active: live'. orders_list(status=OPEN, BTC-USD) returned [] pre-trade, so no ctrl0 order existed to cancel, and that was printed. Starting balances USD 74.279037887874741 / BTC 0 printed. Exactly two orders_create calls exist in the transcript: market BUY quote_size=20 with client_order_id ctrl0mrt1794470331 (unix 1794470331 matches the Bash `date -u +%s` output and the 07:58:54Z created_time) -> order 84dfcb1d... FILLED, avg 73558.02, filled 0.00026944 BTC, fee 0.1783752561792 USD (fill commission in USD, size_in_quote=true 19.8194729088); and market SELL base_size=0.00026944 (= BTC net of fees, already a multiple of base_increment 0.00000001 from products_get) -> e0ec9b8b... FILLED, avg 73556.25, gross 19.818996, fee 0.178370964 USD, net 19.640625036. Evidence files 01-13 and success-evidence.json reproduce these raw tool results verbatim. Arithmetic ties out independently: 74.279037887874741-19.9978481649792=54.281189722895541 (post-buy balance) and +19.640625036=73.921814758895541 (ending balance), net USD -0.357223128979200 (<1 USD); BTC 0 start and 0 end (0 USD drift, <0.50). No tool call errored, no retries, no open orders remained, no withdrawal/transfer/margin, and no credential material appears in any saved file or printed output.

Attempt record

1. —First success verified