Cursor

Cursor is an editor and CLI coding-agent harness. These notes cover its rules, context, and permission behavior rather than the underlying model.

• Put simple project-wide instructions in AGENTS.md; use .cursor/rules/*.mdc when the guidance needs file scoping, intelligent attachment, or manual invocation.
• Use the .mdc extension and explicit rule frontmatter (description, globs, and alwaysApply) for project rules; keep rules focused and version-controlled.
• Use nested AGENTS.md files or scoped rules for genuinely local conventions, and review the resulting instruction set when a task crosses directories.
• Treat CLI shell and file-read permissions as part of the setup. Grant only the command and path access the workflow needs, especially before using non-interactive mode.

• Dropping plain .md files into .cursor/rules and assuming Cursor will load them as project rules.
• Treating the deprecated .cursorrules format as the preferred long-term convention.
• Assuming user or team rules are repository-local, or that an instruction is applied identically across every Cursor surface.
• Attributing rule discovery, context assembly, or permission prompts to the model.

Cursor project rules are inserted as persistent context according to their scope. Cursor CLI supports the IDE rules system and can also read root AGENTS.md and CLAUDE.md files. CLI permissions use separate tokens for shell commands and file reads, and project-specific settings can live in .cursor/cli.json.

Rule scope and available controls vary by Cursor surface and configuration. Confirm the CLI behavior and effective permissions for the version and project being used before relying on a rule or automating writes.