A Claude Code plugin: the model writes one JavaScript program that calls your MCP tools in a sandbox. Only the return value goes back into the context.

Quick start · Usage · Hints · Functions · Permissions · Config

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https://github.com/user-attachments/assets/468c412f-ecae-4e04-a53b-8a291561a052

Without code-mode, the model calls MCP tools one by one, and each full result goes into the context. With code-mode, the model writes one program. The program calls the tools, then filters and joins the results in a sandbox. Only the answer goes into the context.

• Fewer tokens: the intermediate data stays out of the context. The model uses the context for the task.
• Sandbox: the program runs in its own Node process, with no file system and a CPU limit. On macOS, and on Linux where unshare -rn works, it also has no network.
• Hints: short notes for each MCP server tell the model about result formats, required arguments and limits. The model can propose a new hint or the removal of a wrong hint, and you approve it.
• Saved functions: the model can propose a program part that works as a function for later sessions. You read the code and approve it.
• Your permission rules apply: each MCP call in the program gets the normal permission check.

Quick start

You need Claude Code and Node.js 22.13 or later.

Type these commands at the prompt of a Claude Code session:

/plugin marketplace add gabe4coding/claude-code-mode
/plugin install code-mode@claude-code-mode

Start a new session. Then ask for a task that needs several MCP calls.

If you use auto mode, add allow rules for your MCP tools first. Read Permissions.

Example

You ask: "Which of my open Jira issues have no update in the last 14 days?" The model writes one program, for example:

const issues = await call("mcp__claude_ai_Jira__searchJiraIssuesUsingJql", {
  cloudId: "example.atlassian.net",
  jql: "assignee = currentUser() AND statusCategory != Done",
})
const cutoff = Date.now() - 14 * 24 * 3600 * 1000
return issues.issues
  .filter(i => Date.parse(i.fields.updated) < cutoff)
  .map(i => ({ key: i.key, title: i.fields.summary }))

The model gets only the short list, not each full issue.

Documentation

License

MIT. See LICENSE.