docs(plans): patch Plan 5 — test helper sessions/ subdir + sessionlog docstring step

Two corrections applied during Plan 5 execution:

  - Task 2 test helper writeSession now joins a sessions/ subdir so it
    matches the handler's <brainDir>/sessions/*.jsonl scan path.
    (The original heredoc would have produced 0 records in tests.)

  - Task 6 grew a Step 1.5 to update the session_log MCP tool's
    final_status description, picking up a spec requirement that
    didn't translate into a task in the original plan.

docs/superpowers/plans/2026-05-03-pass-rate-logging.md

@@ -167,10 +167,14 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-// writeSession writes one or more JSONL entries to <dir>/<sessionID>.jsonl.
+// writeSession writes one or more JSONL entries to <dir>/sessions/<sessionID>.jsonl.
+// The handler scans <brainDir>/sessions/*.jsonl, so the helper creates the
+// sessions/ subdir to match the production layout.
 func writeSession(t *testing.T, dir, sessionID string, entries ...string) {
 	t.Helper()
-	path := filepath.Join(dir, sessionID+".jsonl")
+	sessionsDir := filepath.Join(dir, "sessions")
+	require.NoError(t, os.MkdirAll(sessionsDir, 0o755))
+	path := filepath.Join(sessionsDir, sessionID+".jsonl")
 	body := ""
 	for _, e := range entries {
 		body += e + "\n"
@@ -942,6 +946,7 @@ Update `cmd/hyperguild/README.md` to document the new `pass-rate` subcommand. Up
 **Files:**
 - Modify: `cmd/hyperguild/README.md` (add `pass-rate` subcommand block)
 - Modify: `CLAUDE.md` (mention `/pass-rate` in the brain HTTP REST API section)
+- Modify: `internal/skills/sessionlog/skill.go` (or wherever the `session_log` MCP tool is registered) — update the `final_status` description from `ok | error | skipped` to `pass | fail | skip (legacy: ok | error | skipped accepted)` so the agent-facing tool definition matches the new SKILL.md vocabulary
 
 - [ ] **Step 1: Update the CLI README**
 
@@ -978,6 +983,21 @@ Skills with no logged invocations return zero counts and `pass_rate: null`
 (indicating "no data", distinct from "always passes").
 ```
 
+- [ ] **Step 1.5: Update the `session_log` MCP tool's `final_status` description**
+
+Find the `session_log` tool registration in the supervisor (`internal/skills/sessionlog/`). Update the `final_status` field's description string to read:
+
+```
+pass | fail | skip (legacy: ok | error | skipped also accepted)
+```
+
+This keeps the agent-facing schema honest — Plan 5's SKILL.md contract uses the new vocabulary. The aggregator normalizes both for backward compat, but the tool's docstring should lead with the new vocabulary.
+
+```bash
+grep -rn "ok | error | skipped\|final_status.*description" ~/dev/AI/hyperguild/.worktrees/pass-rate-endpoint/internal/skills/sessionlog/ ~/dev/AI/hyperguild/.worktrees/pass-rate-endpoint/ingestion/internal/skills/sessionlog/ 2>/dev/null | head
+# Locate the registration; update the description string verbatim.
+```
+
 - [ ] **Step 2: Update CLAUDE.md**
 
 Find the section in `CLAUDE.md` that documents the brain HTTP REST API (look for `## MCP endpoints` or similar). After the existing endpoint list, add a note about `/pass-rate`: