Skill: Cursor

Part of AI Engineering Lab · Developed by Zorost Intelligence AI Lab · zorost.com

1. What it is

Cursor is an AI-native code editor built by Anysphere, a fork of VS Code with an agent bolted into the editor chrome rather than layered on as an extension. Its headline is the Agent: a panel where you hand it a task and it plans, edits multiple files, runs commands, and shows you a diff to review.

Because it is a VS Code fork, your muscle memory and most extensions carry over. The value is that the agent lives inside your editor, so you move fluidly between typing, accepting completions, and delegating whole features, without leaving the window.

• Builder: Anysphere
• Site: https://cursor.com

2. Install

1. Download the app from cursor.com.
2. Sign in with a Cursor account (created on first launch; team management lives in the web dashboard).
3. Optional: import your VS Code settings and extensions during onboarding.

There is also a CLI and an SDK for scripting Cursor's agent outside the editor, the CLI lets you fire a headless agent task from a terminal or CI (cursor-agent-style entry points vary by version), and the SDK exposes the same for programmatic use. For this program the desktop app is the surface that matters; reach for the CLI/SDK only when you need to automate Cursor in a pipeline, where a CLI harness (Claude Code/OpenCode) is usually the cleaner tool anyway.

3. Tab vs. Agent (and Chat)

Cursor has three surfaces, and knowing which to use is most of the skill:

Surface	What it does	Use it for
Tab	Inline, multi-line autocomplete as you type	Micro-edits, boilerplate, completing a line you already started
Chat (⌘L)	Q&A about selected code in a side panel	Explaining code, one-off "why does this fail?" questions
Agent (⌘I, formerly Composer)	Autonomous multi-file planning + editing	Cross-file refactors, "implement this spec," feature work

The Agent is the one this program cares about in Week 12. Open it, paste a short task (or point it at SPEC.md), and let it plan and edit across files. Review the diff, then run your tests. The old name "Composer" still appears in older docs, same thing.

Core loop: open repo → ⌘K for a targeted edit or ⌘I for an agent task → accept Tab suggestions inline → review the agent's full diff → run tests → iterate.

Week 12 in Cursor (concrete). With SPEC.md committed and Rules in place:

1. Open the repo; ⌘I to open the Agent.
2. Type: Read SPEC.md and implement the ETA CLI. Run pytest after; keep the diff minimal.
3. Let it plan and edit; watch the per-file diff.
4. Run pytest -q yourself; if red, send the failing output back to the Agent.
5. Accept, commit on a branch, and open a PR for a human review.

Shortcuts to memorize: ⌘I (Agent), ⌘L (Chat), ⌘K (inline edit), Tab (accept completion), Esc (dismiss a suggestion).

4. Config & rules files: Rules

Cursor reads Rules for persistent project instructions: .cursor/rules/*.mdc (the modern format) and the legacy .cursorrules (a single file). Rules are the Cursor equivalent of CLAUDE.md/AGENTS.md. Commit them to the repo so every teammate's agent follows the same conventions.

Project rules template (.cursor/rules/zorologistics.mdc)

---
description: ZoroLogistics repo conventions for the Cursor agent
---

# ZoroLogistics conventions

## Commands
- Install: `pip install -e .`
- Run tests: `pytest -q`
- Lint: `ruff check src`
- Type check: `mypy src`

## Conventions
- Python 3.11+, type hints on public functions.
- Data lives in `data/`; prefer Parquet, keep committed CSVs under 10 MB.
- Every model ships with a metric + an error-analysis note.

## Never touch without asking
- `data/raw/`, generated input; edit the generator instead.
- `secrets/`, `.env`, `*.key`, `*.pem`, never read these into context.

5. Power moves

• Model selection. Cursor routes each request through the Cursor Router. Its "Auto" modes pick a model per request by trading cost, quality, and reliability:

  Auto mode	Behavior
  Cost	Cheapest model that fits; fixed low per-token rates
  Balance	Middle ground for everyday tasks
  Intelligence	Strongest available model for hard reasoning

  You can also pin a specific model per task. Bringing your own API key is supported for some models, but most users run on Cursor's included pools; check the settings pane for what your plan includes. Set the mode in Settings → Models.

• MCP. Add MCP servers in Cursor settings to give the agent external tools (your Week 16 ZoroLogistics server, for example). Add a server with a name, command, and args, e.g. zorologistics running npx -y @zorologistics/mcp-server, then enable it for the workspace. The agent's tools then include the server's capabilities (track shipment, convert units, query the ETA model).

• Keep tasks narrow, review the full diff. Agent mode is strong because it edits many files; that is also the risk. One focused task at a time, then read everything it touched.

• Watch the usage pool. Third-party and routed models consume your monthly pool fastest; switch the Auto mode (Cost vs Intelligence) to match the task, Cost for mechanical work, Intelligence for hard reasoning.

6. Cost & safety

Pricing tiers (as of Aug 2026: re-verify):

Plan	Price	Notes
Hobby	Free	Limited usage
Pro	$20/mo	Individual, standard usage
Pro+	$60/mo	Higher usage
Ultra	$200/mo	Highest usage
Teams Standard	$40/user/mo	Team billing
Teams Premium	$120/user/mo	Higher team limits
Enterprise	via sales	Pooled usage, SCIM, audit logs

Cursor Router's Auto (Cost) mode bills at fixed rates (~$1.25/1M input, ~$6.00/1M output, ~$0.25/1M cache read), while Balance/Intelligence bill at the routed model's rate; plans also include a monthly "Other Models" pool. Re-check before quoting.

Safety. Review every diff before accepting; commit Rules with a "never touch" list; keep secrets out of prompts and context; for production data use a branch and narrow scope.

7. Team workflows

• Commit Rules to the repo: the single highest-leverage team practice: identical conventions for every engineer's agent.
• Central billing + admin: teams get pooled usage, member management, and (Enterprise) SCIM and audit logs, so usage and policy are governed in one place.
• Shared MCP servers: define team MCP connections once; agents inherit them.
• Code review still belongs to humans: the agent proposes; a teammate still reviews the PR. Treat the agent as a fast first draft, not an approver.

8. Cursor vs. a CLI harness

	Cursor (IDE)	CLI harness (Claude Code / OpenCode)
Where you work	Inside the editor	In the terminal
Best for	Feature work with heavy manual editing; visual diff review	Scriptable, git-native, CI/headless, model-agnostic pipelines
Model choice	Cursor Router (curated + Auto modes)	Any OpenAI-compatible provider (OpenRouter, Ollama, BYO key)
Team/org features	Strong (pooled billing, SCIM, audit)	Depends on harness
Automation	CLI/SDK exists but editor-first	First-class -p/headless

Rule of thumb. You already live in an editor and want completion + an agent with minimal friction → Cursor. You want a scriptable, terminal-native agent you can point at any model and run in CI → a CLI harness. For Week 12, run the ETA CLI build through both and compare, that comparison is the deliverable.

9. Common failures

Symptom	Likely cause	Fix
Agent ignores project conventions	No Rules file committed	Add .cursor/rules/*.mdc and restart the agent session.
Usage pool drains fast	Routing in Intelligence mode for easy tasks	Switch Auto to Cost, or pin a cheaper model.
Tab suggests wrong API	Old model context	Refresh the model/context; check the model selected in settings.
MCP server doesn't appear	Not enabled for the workspace	Add/enable it in Cursor Settings → MCP.
Diff review overwhelming	Task too broad	One narrow task at a time; review per-file.
Agent edits a file it shouldn't	Missing guardrail in Rules	Add the path to Rules' "Never touch" list; re-run.
Version churn / unexpected changes	Model auto-switched mid-task	Pin a model for the task; watch the Auto mode setting.

10. Sources

• Cursor site: https://cursor.com
• Cursor pricing: https://cursor.com/help/account-and-billing/pricing.md
• Cursor Rules: https://docs.cursor.com/context/rules
• Cursor MCP: https://docs.cursor.com/context/model-context-protocol

Pricing and feature tiers change frequently and were captured Aug 2026; re-check the vendor pages before quoting.

---

© 2026 Zorost Intelligence LLC · https://zorost.com