Using Cortex

Using Cortex — When to Consult the Vault

The cortex vault is the user's own knowledge base: distilled Notes, Projects, and Raw session records. This skill decides when consulting it is warranted, and hands the actual search to the cortex-query skill.

Retrieval is worth doing when there is a concrete signal that prior context exists. It is not worth doing on speculation — an unprompted search costs the user tokens and latency, and surfacing unrelated notes pollutes the answer.

Search the vault when any of these is true

1. Explicit request. The user asks for it: "check cortex", "查一下 cortex", "有沒有記錄過", "do I have notes on this".
2. Reference to prior work. The user points at something earlier: "之前那個", "上次的", "我記得有", "我們討論過", "that ticket", "the project we set up", "continue where we left off".
3. Listed topic. The request names a topic that the SessionStart hook actually listed for this vault. The list is authoritative — match against what it showed, not against a guess about what might exist.
4. Resuming a session. The user asks to pick up, continue, or hand off work from a previous session.

In each case, invoke the cortex-query skill rather than searching the vault directly — that skill knows the retrieval infrastructure, including cortex-vec and its fallbacks.

Do not search the vault when

• The user has not given any of the four signals above. A question being difficult, technical, or open-ended is not a signal.
• The user picked option 4 ("直接開始工作") from the SessionStart menu, or skipped the menu. That choice means "do not go to the vault"; honour it for the rest of the session unless the user later asks.
• The user says "don't check cortex", "just answer directly", or similar.
• The task is self-contained: editing code in the current repo, answering from the current turn, or anything the conversation already supplies.

When in doubt, answer directly. If the answer would have been better with vault context, the user can ask — and signal 1 then applies.

How to apply

1. Check the four signals against the user's actual message. If none matches, proceed without the vault and do not mention it.
2. If one matches, invoke cortex-query.
3. If results are relevant, ground the answer in them and cite the source page. If nothing relevant comes back, say so briefly and continue.

Anti-patterns

• ❌ Searching on every message, or at conversation start, "just in case".
• ❌ Treating a hard question as implicit permission to search.
• ❌ Overriding the user's option 4 / "skip the vault" choice.
• ❌ Grepping the vault directly instead of going through cortex-query.
• ❌ Announcing "let me check cortex" when no signal applies.

Why This Skill Exists

The individual cortex skills fire on their own explicit phrases. This skill adds the small set of cases where the user has clearly gestured at prior work without naming a command — so the vault gets consulted when it will actually help, and stays out of the way otherwise.