debug-my-harness

Original：🇺🇸 English

Translated

Diagnose why an agent harness misbehaved by reading the local flight-recorder ledger (.vigiles/runs.jsonl) — which skills fired or got hijacked, which hooks blocked or wrongly allowed, which subagent tool-contract violations happened, and how a skill's trigger rate moved. Use when asked why a skill stopped firing, why a hook didn't block, why the wrong skill ran, or to debug/investigate what the harness actually did. NOT for writing new rules (use strengthen) or editing the spec (use edit-spec).

4installs

Sourcezernie/vigiles

Added on2026-07-03

NPX Install

npx skill4agent add zernie/vigiles debug-my-harness

SKILL.md Content

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Diagnose harness misbehavior from the flight recorder — the local, append-only ledger at

.vigiles/runs.jsonl

that vigiles writes as your harness runs. It records what actually happened, so you debug from evidence instead of guessing.

What's in the ledger

One JSON record per line, each with a

kind

:

hook

— a compiled-hook gate decision:

{event, decision: allow|deny|ask, mode: enforce|observe, rule, cmd, reason}

.

```
agent
```
— a subagent tool-contract decision:
```
{name, tool, allowed, reason}
```
(a
```
false
```
= the agent went outside its lane).
```
skill
```
— a skill activation:
```
{name, fired}
```
.
```
eval
```
— a measured metric:
```
{name, metric, value}
```
(e.g. trigger-rate recall/precision).

capability-diff

— a blast-radius change:

{pr, added, removed, widened}

.

Instructions

Step 1: Read the ledger

Read

.vigiles/runs.jsonl

(JSONL — one record per line; tolerate a torn last line). If it's absent or empty, say so — there's nothing recorded yet; suggest running the harness (or

vigiles audit

) first. Do NOT fabricate records.

Step 2: Answer the specific question, evidence-first

Match the user's question to the ledger:

"Why did skill X stop firing / why does the wrong one run?" — count
```
skill
```
fires by name over time. If X's fire-rate dropped, look for a sibling that fired on the same kinds of prompts (a selection collision) and check their descriptions for overlap. Recommend differentiating or merging the descriptions.
"Why didn't my hook block that?" — find
```
hook
```
records for the event. A
```
decision: allow
```
on something that should be denied, or
```
mode: observe
```
(shadow, never blocks), or the absence of any record, tells you which. Recommend flipping
```
observe
```
→
```
enforce
```
or fixing the gate logic.
"Did a subagent misbehave?" — list
```
agent
```
records with
```
allowed: false
```
: the agent reached for a tool outside its declared contract. Point at the contract to tighten or widen.
"Is it getting worse?" — compare
```
eval
```
metric values (recall/precision) across runs; a downward trend is drift (often after a harness/model upgrade).

Step 3: Recommend a fix, tied to the evidence

Prefer promoting an ignored-but-decidable rule from prose to a deterministic gate: a repeated

agent

violation or a rule the agent keeps breaking → a compiled hook or a tighter tool-contract (the

strengthen

skill can help). A description collision → differentiate the skill descriptions. Always cite the specific records you based the diagnosis on.

Step 4: Offer the next step

If the fix is a spec change, hand off to

edit-spec

. If it's promoting guidance to a linter rule, hand off to

strengthen

. If a behavioral claim needs measuring (does the skill fire now?), hand off to

test-harness

(

measureTriggerRate

).