Codex makes MCP tool schema budgets configurable after fixed limits stripped parameter descriptions

GitHub·medium signalXBlueskyLinkedInCopy link

Codex PR #47936 (merged 2026-09-24) adds mcp_servers.<name>.tool_input_schema_max_bytes, which keeps a 5,000-byte default, and features.code_mode.tool_input_schema_max_bytes, which has a 16,000-byte default. Before this, fixed budgets could strip parameter descriptions from large MCP tools or render their Code Mode input types as 'unknown'. Two days earlier Claude Code made its 2,048-character MCP description cap configurable, so both major coding agents now let MCP server authors buy back schema detail.