Glean adds headless agent building for Claude Code, Cursor and Codex

Glean launched generally available headless agent building on October 21, 2026, letting developers create, test and publish agents as code from Claude Code, Cursor and Codex. Agents are defined by spec.yaml and instructions.md files and run on Glean's managed runtime with access to more than 275 enterprise sources, permissions and audit trails.

• Agents are defined by spec.yaml and instructions.md files under .glean/agents/
• Published agents run on Glean's managed runtime with 275+ enterprise sources
• Auto mode agents are supported; Workflow mode still requires the visual builder
• Installation goes through plugins for Claude Code, Codex and Cursor