{"name":"CLAUDE_AGENT_SDK_DISABLE_MCP_MANIFESTS","slug":"claude-agent-sdk-disable-mcp-manifests","family":"env","title":"Environment variables","noun":"environment variable","description":"The Agent SDK can now read tool lists from in-process MCP servers itself and pass them to the CLI when it starts","description_source":"entry","described_by":{"version":"2.1.281","anchor":"sdk-can-hand-in-process-mcp-server-manifests-to-the-cli-at-i"},"presence":{"first_seen":"2.1.281","removed_in":null,"in_current_build":true,"newest_mined":"2.1.283","builds":3,"mined_builds":126,"first_cited":{"version":"2.1.281","released_at":"2026-09-23 17:01:17","spans":1}},"aliases":[],"entries":[{"version":"2.1.281","anchor":"sdk-can-hand-in-process-mcp-server-manifests-to-the-cli-at-i","heading":"SDK can hand in-process MCP server manifests to the CLI at initialize","line":"The Agent SDK can now read tool lists from in-process MCP servers itself and pass them to the CLI when it starts","released_at":"2026-09-23 17:01:17","reason":"found in this entry's text"}],"entries_total":1,"docs":[],"docs_total":0,"gates":[],"related":[{"name":"CLAUDE_AGENT_SDK_DISABLE_BUILTIN_AGENTS","slug":"claude-agent-sdk-disable-builtin-agents","description":"Set to `1` to disable all built-in [subagent](\/docs\/en\/sub-agents) types such as Explore and Plan. Only applies in non-interactive mode (the `-p` flag). Useful for SDK users who want a blank slate. This also removes `general-purpose`, the subagent Claude Code runs when an Agent tool call omits `subagent_type`. Such a call then fails with [`subagent_type is required`](\/docs\/en\/errors#subagent-type-is-required)"}],"url":"https:\/\/changelogs.core-directive.com\/reference\/env\/claude-agent-sdk-disable-mcp-manifests","family_url":"https:\/\/changelogs.core-directive.com\/reference\/env.json"}