tailtest-cursor is the open-source AI software testing layer for Cursor IDE. It hooks into Cursor's afterFileEdit event: every time Cursor's AI agent edits a file, tailtest queues the file, generates production-shaped scenarios via the R1-R15 rule layer, runs them with your project's existing test runner, and surfaces failures back to Cursor. Hook-based. Deterministic. No prompting required.
Open source (MIT), no telemetry, no SaaS account. Same R1-R15 rule layer + adversarial mode (R15) as the Claude Code, Codex CLI, and Cline variants -- 1,234 plugin tests total across the four hosts.
Read more on tailtest.com · Platform overview · Agent-edit testing deep dive · Cursor docs
From the Cursor Marketplace (recommended):
Search for Tailtest in the Cursor plugin marketplace and click Install. Restart Cursor.
Manual:
git clone https://github.com/avansaber/tailtest-cursor \
~/.cursor/plugins/local/tailtest-cursorRestart Cursor after cloning.
afterFileEdithook fires as the agent writes files, recording each pathstophook fires at turn end and sendstailtest: run tests for: ...- Cursor re-enters the agent -- scenarios are generated, tests are written, run, and reported
Pass = silent. Fail = one line surfaced before the agent moves on.
Create .tailtest/config.json in your project root:
{ "depth": "standard" }Options: simple (2-3 scenarios), standard (5-8, default), thorough (10-15).
See tailtest.com/docs/config for all options.
Same R1-R15 rule layer, same adversarial test mode, different host integration. This repo is the Cursor variant.
- tailtest -- Claude Code plugin (hook-driven)
- tailtest-cursor -- Cursor plugin (hook-driven; this repo)
- tailtest-codex -- Codex CLI plugin (hook-driven)
- tailtest-cline -- Cline plugin (MCP-driven; reaches 8+ editors via Cline's host coverage)
See tailtest.com/demo/cursor for a live walkthrough of this variant, tailtest.com/comparison for a feature matrix across all four, or tailtest.com for the project home.
MIT