Hypercubic
Agentic interface for mainframes and COBOL
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What is Hypercubic?
Hopper is the first agentic development environment for the mainframe, built by Hypercubic for z/OS engineers working with IBM mainframes. It connects AI agents to your mainframe through Model Context Protocol, enabling natural language operations, autonomous workflows, and direct operation inside z/OS from a modern desktop development environment. Users can leverage AI agents to navigate TN3270, inspect datasets, write JCL, debug jobs, query VSAM, interact with CICS, and operate across the full mainframe workflow.
The tool combines four integrated panels that share one mainframe session: a real TN3270 terminal with full PF/PA/attention-key support, a datasets browser for filtering and previewing mainframe files without typing IDCAMS commands, a jobs browser for watching JES queue entries change status in real time without opening SDSF, and a chat agent that reads source, submits jobs, decodes records, and writes changes under user supervision. The AI agent is mainframe-native, shipping with over 50 mainframe-specific tools that drive ISPF by panel ID, write column-strict JCL, decode spool failures into structured diagnostics, and query VSAM as SQL.
Hopper is designed for mainframe developers, COBOL engineers, z/OS operators, and organizations undergoing mainframe modernization. It helps teams debug failed jobs without hunting through SDSF by decoding JESMSGLG, JESYSMSG, and SYSUDUMP into abend codes, failing steps, and source lines. The agent compiles, tests, and ships in one prompt by driving JCL, parsing JES return codes, and NEWCOPYing into CICS, pausing for approval before every change. It runs entirely on your laptop (macOS, Windows, Linux) with nothing installed on the mainframe.
Hypercubic pricing
Pricing model: Freemium
Hopper offers two tiers: Hobby (Free) and Enterprise (Custom). The Hobby tier includes no credit card required, support for macOS/Windows/Linux, ability to connect to your own mainframe, and all core Hopper features. The Enterprise tier includes everything in Hobby plus SAML SSO, MCP Server Access, Admin and Model Controls, org-wide Privacy Controls, No Model Training guarantee, Priority Support, On-prem/VPC Deployment, and SOC 2 & Pen Test Reports. Enterprise customers contact sales for pricing.
Hypercubic pros
- First agentic development environment specifically built for mainframe
- Real TN3270 terminal with full PF, PA, and attention-key support
- AI agent understands z/OS and drives ISPF by panel ID
- Over 50 mainframe-specific tools built into the agent
- Writes column-strict JCL automatically aligned to column 72
- Datasets browser replaces ISPF 3.4 round-trips with one always-visible view
- Jobs browser tracks JES queue in real time without opening SDSF
- Decodes JESMSGLG, JESYSMSG, and SYSUDUMP into structured abend diagnostics
- Queries VSAM as SQL instead of requiring IDCAMS commands
- Compiles, tests, and ships in one prompt with automatic JCL generation
- Pauses for user approval before every mutating action for safety
- Runs on macOS, Windows, and Linux as a desktop app
- Nothing installed on mainframe - connects over standard TN3270 and FTP
- Shared session means agent actions are visible on your terminal screen
- Supports @-tag attachment for datasets, members, and jobs to chat
- Free Hobby tier with all core features and no credit card required
- Agent learns your shop's compile procs, JES config, and CICS regions on connect
Hypercubic cons
- Requires TN3270 access to mainframe (no mainframe needed just to try)
- FTP is optional but required for datasets browser, jobs browser, and builds
- Users must bring their own Anthropic API key (Claude-powered agent)
- Free tier requires connecting to your own mainframe (no hosted mainframe included)
- Production deploys target dev/test only, not production change management
- No bulk data movement capabilities between systems
- No mainframe-side agent - entirely client-side architecture
- Enterprise pricing is custom (no published enterprise rates)
- May require VPN or jump host to reach mainframe from laptop
Frequently asked questions about Hypercubic
What is Hopper?
Hopper is the first agentic development environment for the mainframe. It combines a real TN3270 terminal, mainframe-aware panels for datasets and jobs, and an AI agent that can operate across z/OS workflows including navigating ISPF, inspecting datasets, writing JCL, submitting jobs, parsing JES spool output, analyzing return codes, querying VSAM, interacting with CICS, and explaining failures.
What mainframe protocols does Hopper use?
Hopper uses two standard mainframe protocols: TN3270 for the live terminal session (required) and FTP for files and batch jobs (optional but recommended). Without FTP, the datasets browser, jobs browser, builds, and most agent tools stay disabled. Both run on your laptop connecting to the mainframe over your existing network.
Do I need to install anything on the mainframe?
No. Nothing runs on z/OS. Hopper is entirely client-side and runs on your laptop. Your sysprog doesn't need to deploy anything on the mainframe side. Hopper connects over standard TN3270 and FTP protocols.
What operating systems does Hopper support?
Hopper runs on macOS, Windows, and Linux as a desktop application. You download the installer for your platform, run it, and launch the app.
What AI model powers the chat agent?
The chat agent runs on Claude from Anthropic. Users must bring their own Anthropic API key (starting with sk-ant-), which is stored in the OS keychain. Hopper never sends the key to anything other than api.anthropic.com.
How does the safety model work for mutations?
Each agent action appears as a tool card in chat. Read-only actions like reading a member or listing a PDS execute immediately. Mutating actions like writing a member, submitting a job, or modifying a CICS resource pause for user approval. You see the exact arguments before approving.
Can I use Hopper without my own mainframe?
Yes. If you need access to a mainframe, you can fill out the form on the Hopper page and Hypercubic will send you credentials to try Hopper on their mainframe for free.
What happens when a job fails?
When a job fails, you can send the JOBID to chat with an @-tag. The agent reads the spool, identifies the abend code, failing step, and source line by decoding JESMSGLG, JESYSMSG, and SYSUDUMP. It then proposes a fix and can resubmit with corrected JCL.
Is the terminal panel the same session the agent uses?
Yes. The terminal you see in the panel and the terminal the agent uses are the same shared session. Anything the agent does shows up on your screen (visibility), you can navigate and tell the agent to continue (two-way handoff), and password fields are masked before reaching chat history or logs.
What enterprise features does Hopper offer?
Enterprise includes SAML SSO, MCP Server Access, Admin and Model Controls, org-wide Privacy Controls, No Model Training guarantee, Priority Support, On-prem/VPC Deployment, and SOC 2 & Pen Test Reports. All of these are in addition to everything in the Hobby tier.