Hopper

The first agentic development environment for the mainframe.

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Drives ISPF by panel ID, writes column-strict JCL, decodes spool failures into structured diagnostics, and queries VSAM as SQL.

Drives the JCL, parses JES return codes, NEWCOPYs into CICS, and pauses for your approval before every change.

Hours of SDSF triage in one @-tag. The agent decodes JESMSGLG, JESYSMSG, and SYSUDUMP into the abend code, failing step, and source line.

Works exactly like the TN3270 you've used for years. Full PF, PA, and attention-key support.