🔮 The Pensieve

"A week of numbers in the basin. Vibes are not telemetry."

Every other spell changes the instruction layer. This one finds out whether the changes worked. The alternative — another audit — just re-applies the same judgment that wrote the instructions; only behavior counts.

The counters

Instrument what the spells claim to improve. Core set:

Add repo-specific counters for whatever the audit flagged worst — measure where the disease was.

Read the Needs column before promising anything. A repo with no hooks cannot measure advisory re-fires or injected tokens; a repo with no subagents cannot measure bounces or wrong routings. Five of these eight have a prerequisite most small repos do not meet.

Method

1. Cheap instrumentation only, and confirm the source exists before you promise the counter. A log line in an existing hook, or a grep over transcripts the harness already writes. On Claude Code those are JSONL under ~/.claude/projects/<url-encoded-cwd>/*.jsonl — the path is undocumented and version-specific, so check it (ls ~/.claude/projects/*/ | head) before committing to any transcript-backed counter. A counter whose source you never confirmed is exactly the unexercised check this book grades elsewhere. If it is not there, drop the counter and name which ones you dropped.
2. Drop every counter whose subject is zero. A week of three real numbers beats a table of eight where five sit permanently at 0 and read as improvement. If a counter needs new infrastructure, drop it too.
3. Baseline first when possible. Counters before the fixes land make the delta real. When fixes already landed, the week still gives an absolute floor for the NEXT round.
4. One week of normal work. Not a demo session; the numbers must come from real tasks. Note confounds (an unusual crunch, a new team member, a model version change mid-week).
5. No steering to the numbers. Nobody works differently because the counters run — the point is observing the default.

Bounds

• Scope: instrumentation design and readout. This pass changes no instruction text and proposes no fixes.
• Cap: about 8 counters, and fewer is better. Drop any counter needing new infrastructure, and any whose subject count is zero in this repo — three real numbers beat eight where five are structurally stuck at 0.
• Done when the counter list, its sources, and the readout format are written. The numbers arrive a week later.
• Quote once, at read time; mark anything you cannot re-confirm UNVERIFIED rather than re-reading to check yourself.
• See skills/opus-pocus/references/casting-safety.md for the full rules.

The readout

At week's end, one table: counter · baseline (if any) · this week · verdict (improved / unchanged / worse / can't-tell). Then the decision each number drives:

• Improved → the fix stands; note it as measured in the repo's decision records.
• Unchanged → the instruction text wasn't the bottleneck; candidate for Avada Verbosa.
• Worse → bisect the landed fixes (they're in themed commits — Avada Verbosa's rule).
• Can't-tell → the counter was bad, not the fix; redesign the counter before re-running.

The readout — not another audit — decides whether to run the next ritual, and which spells it needs. That closes the loop: audit → fix → measure → audit only what measurement indicts.