Bitter Frontier What coding agents just made possible, where the bottleneck moved, and what deserves attention.

Evidence record / cursor

A dated record of one change, kept so the writing that cites it can be checked. Compiled from the sources listed below by the research run, not written for reading. The judgment lives in the issues that cite it, below.

2026-10-13-cursor-sdk-subagent-inheritance-is-opt-in-in-1-0-34-and-remains-so-in-1-0

SDK subagent inheritance is opt-in in 1.0.34 and remains so in 1.0.37. TypeScript local SDK embedders can opt Task children into the parent’s executor, workspace and tool-limit configuration. Unset does not transmit the parent’s allowlist headers. Custom tools can also receive a child session identifier for host-owned per-child state. Declaration and vendor-note evidence does not prove every child enforces every restriction at runtime.

Channel: tagged-release (npm 1.0.34 through inspected 1.0.37). Half: both. Date: 2026-09-29 (1.0.34); 2026-10-01 (1.0.35 custom-tool context).

Operator consequence: Configure local.subagentInherit explicitly and probe a child and a nested child against a denied tool. Do not assume parent restrictions propagate. Binding tool state to sessionId can replace ad hoc child tracking, but each executor and the actual workspace remain the embedder’s responsibility.

Receipt

Finding metadata

Confidence
high

Run: 2026-10-13-profile-refresh-2026-09-21_2026-10-13-frontier-v0

Finding ID: 2026-10-13-cursor-sdk-subagent-inheritance-is-opt-in-in-1-0-34-and-remains-so-in-1-0

Profile citations

  • cursor / claim / sdk-child-policy-opt-in

Source links

Primary links, including exact changelog lines when available.

  1. Cursor
    official docs2026-10-13-cursor-sdk-subagent-inheritance-is-opt-in-in-1-0-34-and-remains-so-in-1-0registry.npmjs.org/@cursor/sdk/-/sdk-1.0.34.tgzofficial docs2026-10-13-cursor-sdk-subagent-inheritance-is-opt-in-in-1-0-34-and-remains-so-in-1-0registry.npmjs.org/@cursor/sdk/-/sdk-1.0.37.tgzofficial docs2026-10-13-cursor-sdk-subagent-inheritance-is-opt-in-in-1-0-34-and-remains-so-in-1-0registry.npmjs.org/@cursor%2fsdk/1.0.34official docs2026-10-13-cursor-sdk-subagent-inheritance-is-opt-in-in-1-0-34-and-remains-so-in-1-0registry.npmjs.org/@cursor%2fsdk/1.0.37official docs2026-10-13-cursor-sdk-subagent-inheritance-is-opt-in-in-1-0-34-and-remains-so-in-1-0web.archive.org/web/20261007020951/https://cursor.com/docs/release-notesofficial docs2026-10-13-cursor-sdk-subagent-inheritance-is-opt-in-in-1-0-34-and-remains-so-in-1-0cursor.com/docs/release-notes/sdk#sep-29-2026

Versioned source: run artifact