thoughtbox:debug

A structured debugging workflow for unexpected software behavior, such as a failed test, a production incident, or a fix that did not work. It records surprises and requires a testable explanation after repeated unexpected results.

In plain words
What is it for?
Use it to define a problem, plan an investigation with a fallback action, test hypotheses, and assess each result before continuing.
Why use it?
It reduces random trial-and-error when debugging becomes confusing or initial fixes fail.

Skill for Claude CodeCodex

Install

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.

agentmods
npx agentmods add skills/kastalien-research/thoughtbox/thoughtbox-debug
Any agent
npx skills add Kastalien-Research/thoughtbox --skill thoughtbox-debug
Clone the repo
git clone --depth 1 https://github.com/Kastalien-Research/thoughtbox

Made for: Claude Code, Codex.

Per session 80 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,056 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5 $0.00080 $0.01056
Opus 5 $0.00040 $0.00528
Sonnet 5 $0.00016 $0.00211
Haiku 4.5 $0.00008 $0.00106

Measured 3d ago against content hash 45742f29235c, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

thoughtbox: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 3d 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.

.agents/skills/thoughtbox-debug/SKILL.md · 150 lines

How it starts

The opening of the file, as written. The whole thing — 150 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Thoughtbox Debug

Guided debugging workflow built on the Ulysses surprise-gated protocol. Prevents reactive debugging spirals by forcing structured hypotheses after repeated surprises.

Core Mechanic: The S-Register

The S-register (surprise counter) is the discipline mechanism. Each unexpected outcome increments S. At S=2, stop and form a falsifiable hypothesis before continuing. This breaks the "try something, doesn't work, try something else" spiral.

Phase 1: Initialize

Start a debugging session. Define the problem and any constraints.

async () => {
  return await tb.ulysses({
    operation: "init",
    problem: "$ARGUMENTS",
    constraints: [
      // Hard limits on what you can change
    ]
  });
}

This starts a session with S=0. State the problem precisely — vague problems produce vague debugging.

Phase 2: Plan-Act-Assess Loop

Repeat this cycle for each investigation step.

2a. Plan with a pre-committed recovery action

Before investigating, declare what you will do AND what you will do if it fails. The recovery action prevents post-hoc rationalization.

async () => {
  return await tb.ulysses({
    operation: "plan",
    primary: "Check CI environment variables vs local .env",
    recovery: "If env vars match, check node version differences"
  });
}

2b. Execute

Run the primary action using whatever tools are needed (Read, Grep, Bash, etc.). Gather evidence. Do not interpret yet.

2c. Assess the outcome

Report whether the result matched your expectation.

async () => {
  return await tb.ulysses({
    operation: "outcome",
    assessment: "unexpected",  // or "expected"
    severity: "minor",         // or "major"
    details: "Env vars are identical — rules out config differences"
  });
}
  • "unexpected" increments S. "expected" leaves S unchanged.
  • Be honest. Calling a surprise "expected" defeats the protocol.

Phase 3: Forced Reflection (S=2)

When S hits 2, the protocol blocks further plan operations until you reflect. This is the mechanism that prevents spiraling.

Read the full file on GitHub · 150 lines

Changes

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.

  1. 3d ago First seen · 150 lines · 80 tokens per session scan A 45742f29235c

Subscribe to this mod's changes

thoughtbox:debug is a skill published in the GitHub repository Kastalien-Research/thoughtbox (64 stars, last pushed 1mo ago), licensed MIT. It adds 80 tokens to every session and 1,056 once invoked, about $0.0004 per session on Opus 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 2026-08-30.

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