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+---
+summary: os-adr Eval B (unprompted write-trigger & retrieval) grid results for haiku/sonnet — haiku never self-triggers the ADR system, sonnet passes 5/8 with two near-miss failures — read before designing any follow-up eval on unprompted-consultation behavior.
+tags:
+  - scope/global
+  - type/reference
+  - project/cc-os
+  - tool/os-adr
+  - domain/llm-evaluation
+source: cc-os
+date: 2026-07-03
+---
+
+# os-adr Eval B grid results (2026-07-03)
+
+Eval B measures whether a model notices **on its own** that an Architecture Decision Record
+system is relevant — without being explicitly told to invoke it. Two axes per scenario: (a)
+did the model touch the ADR system unprompted (mechanical, from tool_use), (b) was the specific
+outcome correct (right ADR cited, or a new ADR actually proposed/created). See
+`cc-os/plugins/os-adr/eval-b/README.md` for full harness design (headless-only `claude -p` runs,
+so a real SessionStart hook fires — in-session Agent-tool subagents cannot validly stand in for
+this, since they don't get a fresh hook invocation against the sandbox cwd).
+
+## Grid (1 rep/cell)
+
+| Scenario | Haiku | Sonnet |
+|---|---|---|
+| W1 (persistence choice) | FAIL | **PASS** |
+| W2 (convention change) | FAIL | **PASS** |
+| W3 (reversal) | FAIL | FAIL — doesn't propose recording the decision |
+| R1 (direct conflict) | FAIL | FAIL — misses the direct-conflict retrieval |
+| R2 (distractor) | FAIL | **PASS** |
+| R3 (mid-task question) | FAIL | **PASS** |
+| R4 (graph one-hop) | FAIL | **PASS** |
+| R4-nograph (degradation check) | FAIL (expected) | FAIL (expected) |
+
+**Haiku: 0/8.** Never touches `os-adr:*` / `bin/adr-*` / `docs/adr/` unprompted in any
+scenario — total absence of self-triggered consultation, not a near-miss.
+
+**Sonnet: 5/8.** Two real misses: W3 (reversal — doesn't propose recording the decision) and R1
+(direct-conflict retrieval — doesn't catch it and cite the correct ADR).
+
+`R4-nograph` failing on both tiers is the **expected** result — it's a degradation check, only
+meaningful paired with an R4 PASS on the same tier (confirms the Graphify one-hop layer did
+real work). Sonnet has that pairing (R4 PASS + R4-nograph FAIL); haiku doesn't, since R4 already
+failed for haiku.
+
+## Observations
+
+- **This reads as a prompting/wording issue, not a capability gap.** Sonnet already succeeds on
+  5 of 8 scenarios, and its two failures (W3, R1) are near-misses rather than blind spots —
+  the model is clearly capable of the behavior when the trigger is salient enough. Haiku's
+  total 0/8 plus sonnet's two-scenario gap both point toward the SKILL.md wording and/or the
+  SessionStart hook note text (`plugins/os-adr/hooks/session_start.py`) not being salient
+  enough as an unprompted trigger — not toward a reasoning or tool-use failure.
+- **Open question, not yet resolved:** whether in-session subagents could ever validly
+  substitute for part of this measurement. Flagged as suspect given the hook-context
+  requirement established for Eval B (in-session subagents inherit the parent session and never
+  get a fresh SessionStart against the sandbox cwd) — worth re-examining specifically for
+  scenarios where the hook note itself isn't the variable under test, but not assumed solved
+  here.
+- **Next step (not started — future session):** design a follow-up eval that iterates
+  SKILL.md / hook-note wording to raise the unprompted-trigger rate, using the existing
+  `/autoresearch` Classic-loop discipline (checker/fixtures/scenarios/rubric frozen, only
+  wording moves — see `plugins/os-adr/eval-b/README.md`). **That eval should point back at
+  this note** for the baseline numbers and the prompting-issue hypothesis, so the loop has a
+  concrete before/after to compare against.
+
+## Source
+
+- cc-os repo, `plugins/os-adr/eval-b/` (harness) and `plugins/os-adr/eval-b/README.md` (status)
+- Full TSV: `/tmp/adr-eval-b-grid/results.tsv` (ephemeral — not committed, per harness design)
+- Doc updates committed at cc-os `5b399d5`
diff --git a/journal/2026-07-03.md b/journal/2026-07-03.md
index 68107ff..9d088b4 100644
--- a/journal/2026-07-03.md
+++ b/journal/2026-07-03.md
@@ -394,3 +394,10 @@ tags: [scope/global, type/log]
 **Reason:** other
 **Vault notes touched:**
 (none)
+
+## Session — 2026-07-03T21:32:58Z
+
+**Project:** /tmp/adr-eval-b-grid/R2-sonnet-r1
+**Reason:** other
+**Vault notes touched:**
+(none)