Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add SienkLogic/plan-build-run --skill debuggit clone --depth 1 https://github.com/SienkLogic/plan-build-runWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/sienklogic/plan-build-run/debug)<a href="https://agentmods.dev/skills/sienklogic/plan-build-run/debug"><img src="https://agentmods.dev/badge/skills/sienklogic/plan-build-run/debug/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/sienklogic/plan-build-run/debug"><img src="https://agentmods.dev/badge/skills/sienklogic/plan-build-run/debug.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00013 | $0.04728 |
| Opus 5.5 | $0.00005 | $0.01891 |
| Sonnet 5.5 | $0.00003 | $0.00946 |
| Haiku 4.5 | $0.00001 | $0.00473 |
Grade A, and why
debug scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 580 lines — stays where its author put it; the contents beside it link to each section on GitHub.
STOP — DO NOT READ THIS FILE. You are already reading it. This prompt was injected into your context by Claude Code's plugin system. Using the Read tool on this SKILL.md file wastes ~7,600 tokens. Begin executing Step 1 immediately.
Step 0 — Immediate Output
Before ANY tool calls, display this banner:
╔══════════════════════════════════════════════════════════════╗
║ PLAN-BUILD-RUN ► DEBUGGING ║
╚══════════════════════════════════════════════════════════════╝
Then proceed to Step 1.
/pbr:debug — Systematic Debugging
You are running the debug skill. Your job is to run a structured, hypothesis-driven debugging session that persists across conversations. You track every hypothesis, test, and finding in a debug file so work is never lost.
This skill spawns Task(subagent_type: "pbr:debugger") for investigation work.
References
references/questioning.md— Investigation questioning patterns: progressive depth, exploratory questions, concrete options (not open-ended)references/ui-brand.md— Status symbols, banners, error boxes for issue reporting
Context Budget
Reference: skills/shared/context-budget.md for the universal orchestrator rules.
Reference: skills/shared/agent-type-resolution.md for agent type fallback when spawning Task() subagents.
Additionally for this skill:
- Never perform investigation work yourself — delegate ALL analysis to the debugger subagent
- Minimize reading debug file content — read only the latest hypothesis and result section
- Delegate all code reading, hypothesis testing, and fix attempts to the debugger subagent
Core Principle
Debug systematically, not randomly. Every investigation step must have a hypothesis, a test, and a recorded result. No "let me just try this" — every action has a reason and is documented.
Flow
Step 1: Ensure Debug Directory Exists
CRITICAL (no hook) -- DO NOT SKIP: Create debug directory before any file writes.
What ships with it
2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 1mo ago First seen · 580 lines · 13 tokens per session scan A 3b17d822e3ee
debug is a skill published in the GitHub repository SienkLogic/plan-build-run (19 stars, last pushed 6mo ago), licensed MIT. It adds 13 tokens to every session and 4,728 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.
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