Cline/Windsurf/Kilo/Antigravity install skips silently if the project's rules file contains the substring "rtk" — e.g. "RTK Query" in a Redux project #3406

The project-scoped installers decide "already configured" by substring-searching the rules file for RTK or rtk. Any unrelated occurrence makes the install a no-op that reports success.

Provenance: AI-assisted source audit, human-directed, at v0.44.2 (700bdde). Read from source; rtk init was not executed.

The check

src/hooks/init.rs:1640 (Cline), and identically at :1685 (Windsurf), :1738 (Kilo Code), :1796 (Antigravity):

let existing = fs::read_to_string(&rules_path).unwrap_or_default();
if existing.contains("RTK") || existing.contains("rtk") {
    println!("\nRTK already configured for Cline in this project.\n");
    println!("  Rules: .clinerules (already present)");
}

This is a bare substring test over the whole file.

Why it misfires

RTK is the standard abbreviation for Redux Toolkit, and RTK Query is one of its most-used features. A JavaScript or TypeScript project whose .clinerules says something like:

Prefer RTK Query for data fetching; do not add axios.

will make rtk init --agent cline print "RTK already configured for Cline in this project" and write nothing. rtk is then simply not installed, and the message says the opposite.

Lowercase rtk matches even more broadly — any path, package name or prose containing those three letters in sequence.

The same file has the precise version

For Claude, Cursor and Droid, idempotency is exact rather than fuzzy: hook_already_present (init.rs:1120), and :3676 / :3140, compare the actual hook command — is_claude_hook_command shell-splits and checks three tokens. Only these four project-rules installers use a substring.

Suggested fix (untested)

Search for the block markers the installer itself writes (RTK_BLOCK_START / the exact heading it emits) rather than for the letters rtk. That is what makes the check idempotent rather than merely cautious, and it is already the approach used on the marker-based CLAUDE.md path.

Related, same four installers

These write an rtk block into .clinerules / .windsurfrules / .kilocode/rules/rtk-rules.md / .agents/rules/*.md (init.rs:1660, :1705, :1760, :1817) and no uninstall path exists for any of them — reported separately in the uninstall-dispatch issue. So a block appended into a user-authored, usually-committed rules file cannot be removed by rtk.