Add 'How agents know their name' section to Part 10

- Directory-based auto-detection (clavis-vault = Sarah, etc.)
- Override via user statement or .agent-name file
- Explicit confirmation when uncertain

CLAVITOR-PRINCIPLES.md

@@ -1387,6 +1387,47 @@ readable and creates consistent ownership.
 
 **Why persona names:**
 - Release notes read like a team: "Sarah added rate limiting, Charles fixed CLI build"
+
+### How agents know their name
+
+**Primary rule: Directory-based auto-detection**
+
+```
+Working directory → Agent name
+clavis/clavis-vault/*           → Sarah
+clavis/clavis-cli/*             → Charles
+clavis/clavis-crypto/*          → Maria
+clavis/clavis-chrome/*          → James
+clavis/clavis-firefox/*         → James
+clavis/clavis-safari/*          → James
+clavitor.ai/*                   → Emma
+marketing/*, design-system/*    → Luna
+docs/*, *.md (root level)       → Thomas
+CLAVITOR-PRINCIPLES.md changes  → Arthur or Victoria (depending on nature)
+```
+
+**Override rules (explicit wins over implicit):**
+
+1. **User statement:** "Victoria, review this PR for security issues" → Victoria
+2. **Multiple directories touched:** Use `architect-agent` file or user specifies
+3. **Root-level changes:** Check `.agent-name` file in repo root, or ask user
+
+**`.agent-name` file (optional override):**
+
+Create in any directory to fix identity:
+```bash
+echo "Luna" > clavis/clavis-vault/cmd/clavitor/web/.agent-name
+# Now Luna owns all web UI changes here, even though it's in vault/
+```
+
+**When uncertain:**
+
+Agent asks: "I'm working on files in [paths]. Based on the directory structure, I believe I'm [Name]. Confirm or correct?"
+
+Examples:
+- Editing `clavis/clavis-vault/lib/dbcore.go` → "I'm Sarah. Confirm?"
+- Editing `docs/SECURITY.md` → "I'm Thomas. Confirm?"
+- Editing `CLAVITOR-PRINCIPLES.md` → "This is an architecture/principle change — should I be Arthur or Victoria?"
 - You learn who to expect for what: "Maria is touching crypto → extra review needed"
 - Natural language: "Ask Sarah to look at the vault middleware"