We taught Agent Skill Sync to read the room

Quick recap from the first post: Agent Skill Sync is a small VS Code / Cursor extension that pulls Cursor rules and skill packages from a GitHub repo (or a custom registry) and drops them where Cursor actually looks, .cursor/rules and .cursor/skills. Free on Open VSX: KeskaLabsAB / agent-skill-sync.

The plugin we showed off in the last post nailed the boring half: getting curated skills out of git and into the editor without a copy-paste ceremony. Then the catalog grew. And the moment a teammate opened the panel, blinked at twenty-something skills, and asked “okay… which of these do I actually want?”, we knew the next problem to solve.

This post is about that. Discovery. Less scrolling, more “oh, that one.”

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First, the unsexy bit

Before we could put a recommender on top, the foundation had to behave. A quiet polish pass cleaned up two things you’ll notice mostly because they stopped annoying you:

• First-run reliability: the welcome / setup prompt no longer flickers, double-fires, or leaves you staring at a blank panel on a fresh install.

• Browse tree expand/collapse: nested folders now toggle the way you expect them to. Subtle, deeply annoying when it was wrong.

Onward.

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A Recommended tab, finally

We added a third tab to the Skill Manager, next to Manage and Browse, called Recommended. It looks at your workspace and ranks the catalog for you.

“Looks at your workspace” isn’t magic. It reads the ordinary tells:

• which languages the repo uses,

• what’s in package.json / pyproject.toml / Cargo.toml / go.mod (your dependencies),

• a few path markers (Dockerfiles, monorepo configs, etc.),

• which VS Code / Cursor extensions you have installed,

• and AGENTS.md if you keep one.

Each catalog skill can declare triggers in its SKILL.md (languages, dependencies, files, keywords). The tab cross-references the two and surfaces the matches with a small chip telling you why, “Keywords matched AGENTS.md [rest, api, endpoint],” that kind of thing. No surprises, no black box.

We improved Browse at the same time: every node in the repository tree got a checkbox, so you can enable a skill straight from the tree without round-tripping through Manage. Skill packages and standalone rules are treated separately, so enabling a package doesn't accidentally toggle individual files inside it.

The Manage tab. Toggling a skill writes the whole package under .cursor/skills/<name>/. The SKILL.md on the right is what feeds the recommender: triggers.dependencies, triggers.files, triggers.keywords.

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Then we let an LLM rank them

Heuristic matching is great until the catalog gets opinionated and your repo gets messy. So the Recommended tab now tries an LLM first and only falls back to keyword matching if no model is available. The chain in this exact order is:

1. vscode.lm: VS Code’s Language Model API. If you have GitHub Copilot installed in VS Code, this is already wired up. (Heads up: Cursor doesn’t expose its built-in models through vscode.lm yet, so Cursor users land on step 2 or further.)

2. Cursor SDK: if you’ve set a key.

3. OpenAI: if you’ve set a key.

4. Anthropic: if you’ve set a key.

5. Heuristic: the original signal-matching logic. We label the result with a HEURISTIC badge so you’re never wondering which mode you’re in.

Keys are optional and stored in VS Code Secret Storage, not your settings.json. Set them with Skill Sync: Set OpenAI Recommendation Key (and friends), nuke them with Clear Recommendation API Keys. We don’t see them, we don’t want them.

Results are cached per-workspace with a TTL so the panel doesn’t hit a model every time you blink. Hit Refresh to bypass the cache when something obviously changed.

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Ask the Agent: keep the smart part inside Cursor

Now the part Cursor users will care about most.

If you don’t want to wire up an API key, you don’t have to. Click Ask the Agent and the extension does three things:

1. Builds a context-rich prompt. Your workspace fingerprint (languages, deps, monorepo flag, AGENTS.md presence), the current synced catalog candidates, and the skills you’ve already enabled.

2. Opens it pre-filled in Cursor’s composer, via Cursor’s own prompt deeplink. You see a Create chat with prompt sheet first: review, then Create Chat. (We also copy the same prompt to your clipboard, just in case.)

3. Routes the request to a bundled subagent, agents/skill-recommender.md, which is shipped with the repo as a Cursor Plugin. Enable the plugin once and the subagent shows up like any other agent.

The result: no API key, no LLM cost, and the model that already lives inside Cursor (the one you’re paying for anyway) does the ranking, with the context that only the extension can collect.

Recommended on the left, Ask the Agent on the right. The prompt isn’t a one-liner, it includes the workspace fingerprint and the live catalog so the agent has something to reason about.

A small but important detail: oversized catalogs are automatically trimmed to fit Cursor’s deeplink size budget, so this doesn’t silently break on big skills repos.

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A new file you didn’t know you wanted: catalog.json

Whenever you sync or browse, the extension now writes a tiny manifest at:

.cursor/skill-sync/catalog.json

Metadata only, no skill bodies. It’s the file the bundled subagent (and any tooling you build on top) reads to know what’s actually in your team catalog right now. If you’ve ever wanted “the agent should know which skills are available without me copy-pasting,” this is that.

The plugin layout follows the official Cursor plugin spec: manifest at .cursor-plugin/plugin.json, agent files in agents/ next to it. Two paths, because that's what Cursor requires, not because we like extra folders.

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How to try it (the short path)

1. Install Agent Skill Sync (currently 0.7.0) from Open VSX, or the VS Code Marketplace.

2. Connect a skills repo (owner/repo): yours, your team’s, or play with a public one.

3. Open the Skills sidebar (Ctrl+Alt+S / Cmd+Alt+S) and click the Recommended tab.

4. Either:

   • Don’t configure anything → you get heuristic ranking (badge says HEURISTIC), or

   • Hit Ask the Agent → Cursor’s composer opens with the prompt prefilled, no key needed (works best with the bundled skill-recommender plugin enabled), or

   • Set a provider key via Skill Sync: Set … Recommendation Key → ranking goes live with that model on every refresh.

Toggle what looks useful. Files land under .cursor/rules and .cursor/skills like before. Done.

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Why this matters more than “a new tab”

Curated skill repositories are starting to look a lot like internal package registries: versioned, reviewed, owned by the platform team. The next problem after “how do I get them into the editor” has always been: which ones, for this codebase, today?

We don’t think the answer is a longer onboarding doc. The answer is the editor noticing what you’re working on and saying so. The first cut of that is the dumb-but-honest version: signal matching with reason chips. The second cut hands the same context to a model, and if no model’s around, to your own Cursor agent in one click.

If something’s weird, open an issue. If it just works, enable a skill nobody on the team has tried yet and tell us if the ranking was right.

Keska Labs