Concept

Code Mode

MCP design that exposes few tools (e.g. search + execute) and runs agent-supplied code server-side to keep token usage fixed.

Published February 23, 2026

Definition

Code Mode is a way to design an MCP server for very large APIs: instead of one tool per endpoint (which would exhaust the context window), the server exposes only two tools (e.g. search() to explore the spec, execute() to call the API). The agent sends code (e.g. JavaScript) that runs in a sandbox on the server; the token footprint stays fixed (~1,000 tokens) regardless of API size.

See also

Related: MCP, Token, OpenAPI. See Code Mode: give agents an entire API in 1,000 tokens.