trace

trace is a skill for Claude Code, Codex from myths-labs/muse. It costs 18 tokens per session (1,988 once invoked), scanned A, a copy of trace, MIT.

An evidence-based process for explaining why an observed result happened by comparing possible causes. It coordinates multiple tracing hypotheses and tests them with evidence.

In plain words
What is it for?
Use it to investigate runtime bugs, regressions, performance issues, architecture questions, postmortems, and configuration behavior.
Why use it?
It helps with ambiguous problems where the cause is unclear and jumping straight to a fix could send the investigation in the wrong direction.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: agent in frontmatter.

Good fit Use it to investigate runtime bugs, regressions, performance issues, architecture questions, postmortems, and configuration behavior.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/myths-labs/muse/trace
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.

Any agent
npx skills add myths-labs/muse --skill trace
Clone the repo
git clone --depth 1 https://github.com/myths-labs/muse

Made for: Claude Code, Codex.

Wrote 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.

agentmods badge for trace

README.md
[![agentmods](https://agentmods.dev/badge/skills/myths-labs/muse/trace/github.svg)](https://agentmods.dev/skills/myths-labs/muse/trace)
Your own site
<a href="https://agentmods.dev/skills/myths-labs/muse/trace"><img src="https://agentmods.dev/badge/skills/myths-labs/muse/trace/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.

agentmods 80×15 button for trace

Your own site · 80×15
<a href="https://agentmods.dev/skills/myths-labs/muse/trace"><img src="https://agentmods.dev/badge/skills/myths-labs/muse/trace.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 18 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,988 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 84% copy Near-identical to another mod 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 5.1 $0.00018 $0.01988
Opus 5 $0.00009 $0.00994
Sonnet 5 $0.00004 $0.00398
Haiku 4.5 $0.00002 $0.00199

Measured 6d ago against content hash 75703088b0eb, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

trace 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 6d 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.

Origin

This is a copy

84% identical to trace — 5 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

skills/toolkit/trace/SKILL.md · 263 lines

How it starts

The opening of the file, as written. The whole thing — 263 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Trace Skill

Use this skill for ambiguous, causal, evidence-heavy questions where the goal is to explain why an observed result happened, not to jump directly into fixing or rewriting code.

This is the orchestration layer on top of the built-in tracer agent. The goal is to make tracing feel like a reusable OMC operating lane: restate the observation, generate competing explanations, gather evidence in parallel, rank the explanations, and propose the next probe that would collapse uncertainty fastest.

Good entry cases

Use /oh-my-claudecode:trace when the problem is:

  • ambiguous
  • causal
  • evidence-heavy
  • best answered by exploring competing explanations in parallel

Examples:

  • runtime bugs and regressions
  • performance / latency / resource behavior
  • architecture / premortem / postmortem analysis
  • scientific or experimental result tracing
  • config / routing / orchestration behavior explanation
  • “given this output, trace back the likely causes”

Core tracing contract

Always preserve these distinctions:

  1. Observation -- what was actually observed
  2. Hypotheses -- competing explanations
  3. Evidence For -- what supports each explanation
  4. Evidence Against / Gaps -- what contradicts it or is still missing
  5. Current Best Explanation -- the leading explanation right now
  6. Critical Unknown -- the missing fact keeping the top explanations apart
  7. Discriminating Probe -- the highest-value next step to collapse uncertainty

Do not collapse into:

  • a generic fix-it coding loop
  • a generic debugger summary
  • a raw dump of worker output
  • fake certainty when evidence is incomplete

Evidence strength hierarchy

Treat evidence as ranked, not flat.

From strongest to weakest:

  1. Controlled reproductions / direct experiments / uniquely discriminating artifacts
  2. Primary source artifacts with tight provenance (trace events, logs, metrics, benchmark outputs, configs, git history, file:line behavior)
  3. Multiple independent sources converging on the same explanation
  4. Single-source code-path or behavioral inference
  5. Weak circumstantial clues (timing, naming, stack order, resemblance to prior bugs)
  6. Intuition / analogy / speculation

Read the full file on GitHub · 263 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. 6d ago First seen · 263 lines · 18 tokens per session scan A 75703088b0eb

Subscribe to this mod's changes

trace is a skill published in the GitHub repository myths-labs/muse (32 stars, last pushed 3d ago), licensed MIT. It adds 18 tokens to every session and 1,988 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. It is 84% identical to trace, differing in 5 lines, and is treated as a copy.