diff --git a/README.md b/README.md
index 986a7c7..8534814 100644
--- a/README.md
+++ b/README.md
@@ -102,11 +102,21 @@ clank --system @prompts/review-sh.md -c script.sh -m "review the script"
 
 ## Keeping it fast
 
-**2026-09-22 one-shot** (same `opencode-go/glm-5.3-flash`, tools off): clank ~5
-MB / 0.75 s vs omp ~371 MB / 3.4 s, pi ~177 MB / 2.2 s, OpenCode ~562 MB / 5.7 s
-— pipe stage vs agent harness; dated record in
-[docs/history/clank-vs-agents-2026-09-22.md](docs/history/clank-vs-agents-2026-09-22.md).
+### Harness cost (dated)
+
+**2026-09-22** one-shot on the same Go model (`opencode-go/glm-5.3-flash`),
+tools off, prompt `→ pong`. This is **pipe vs agent CLI**, not a quality
+benchmark — agent harnesses still pay TUI/runtime tax with `--no-tools`.
 
+| | wall median | peak RSS |
+|---|---:|---:|
+| **clank** (pipe) | **0.75 s** | **~5 MB** |
+| pi | 2.2 s | ~177 MB |
+| omp | 3.4 s | ~371 MB |
+| opencode | 5.7 s | ~562 MB |
+
+Full method, caveats, and runs:
+[docs/history/clank-vs-agents-2026-09-22.md](docs/history/clank-vs-agents-2026-09-22.md).
 
 The model is the constraint (clank's own share is 1 ms of startup), so the lever
 is the tokens you pay for: