diff --git a/.claude/CODING_GUIDELINES.md b/.claude/CODING_GUIDELINES.md
index 8ea1e4c..bce18c3 100644
--- a/.claude/CODING_GUIDELINES.md
+++ b/.claude/CODING_GUIDELINES.md
@@ -65,9 +65,12 @@ powershell.exe -Command '$x = 5; Write-Host $x'
 
 ---
 
-## Context Lookup — GrepAI First
+## Context Lookup — search before reading (wiki first for known entities)
 
-Before reading any file for context, search with GrepAI or Grep. Only open a file when you need its full content for editing or line-by-line review.
+For a **known entity's facts** (a specific client/project/system), check the **wiki** first — it is
+the synthesized truth layer. For **code and discovery**, search with GrepAI or Grep before reading
+any file; only open a file when you need its full content for editing or line-by-line review. Full
+rule: `.claude/standards/context-lookup/grepai-first.md`.
 
 | Goal | Tool |
 |------|------|
diff --git a/.claude/standards/context-lookup/grepai-first.md b/.claude/standards/context-lookup/grepai-first.md
index 2fd9d6a..d0e3dd8 100644
--- a/.claude/standards/context-lookup/grepai-first.md
+++ b/.claude/standards/context-lookup/grepai-first.md
@@ -1,12 +1,22 @@
 ---
 name: grepai-first
-description: Search with GrepAI or Grep before opening any file for context; Read only when full content is needed
+description: Wiki first for known-entity facts; then search with GrepAI/Grep before opening any file for code/discovery; Read only when full content is needed
 applies-to: all
 ---
 
-# Context Lookup — GrepAI First
+# Context Lookup — search before reading (wiki first for known entities)
 
-Before reading any file for context, search with GrepAI or Grep. Only open a file when you need its full content for editing or line-by-line review.
+Two-part rule:
+
+1. **Known-entity facts** (a specific client/project/system — its IPs, creds paths, architecture):
+   check the **wiki** (`wiki/`) FIRST. It is the synthesized truth layer and is already distilled —
+   cheaper than re-deriving from raw logs/code.
+2. **Everything else** (code, discovery, un-compiled detail): search with **GrepAI or Grep before
+   opening any file**. Only open a file when you need its full content for editing or line-by-line
+   review.
+
+GrepAI's irreplaceable value is **code** (call-graph tracing over the Rust+TS corpus the wiki can't
+see). Do NOT GrepAI something the wiki already answers — that's redundant overlap.
 
 ## Lookup table
 
@@ -18,8 +28,9 @@ Before reading any file for context, search with GrepAI or Grep. Only open a fil
 | Find what a function calls | `grepai_trace_callees` |
 | Full file content needed (edit, review) | `Read` |
 | Recent changes to a file | `git log`, then `Read` specific file |
-| "What did we do with X?" | `grepai_search` over session logs |
-| "How is Y configured?" | `grepai_search` before checking any specific file |
+| "What did we do with client/system X?" | **wiki article first**, then `grepai_search` over session logs for detail below the wiki's summary |
+| "How is Y configured?" (known entity) | **wiki first**, then `grepai_search` / the specific file |
+| "How is Y configured?" (code/unknown) | `grepai_search` before opening any file |
 
 ## Token cost rationale