trace-qa

A guide for examining agent execution traces, which are records of the steps, tool calls, messages, and results produced during a run.

In plain words
What is it for?
Use it to debug agent behavior, review a run, inspect individual tool calls or model messages, and measure execution efficiency.
Why use it?
It helps explain failed runs, tool-call order, token usage, timing, and the agent’s final answer without inspecting the entire trace at once.

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/dp-archive/archive/trace-qa
Any agent
npx skills add dp-archive/archive --skill trace-qa
Clone the repo
git clone --depth 1 https://github.com/dp-archive/archive

Made for: Claude Code, Codex.

Per session 72 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 803 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 $0.00072 $0.00803
Opus 5 $0.00036 $0.00402
Sonnet 5 $0.00014 $0.00161
Haiku 4.5 $0.00007 $0.00080

Measured 3d ago against content hash d7dd643eabb6, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

trace-qa 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.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/fetch_trace.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

seed_skills/trace-qa/SKILL.md · 81 lines

How it starts

The opening of the file, as written. The whole thing — 81 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Trace QA

Analyze agent execution traces to answer questions about what happened, why it failed, how efficient it was, or any other aspect of the run.

Workflow

Always start with overview to understand the trace before diving into details.

1. Get the overview first

python scripts/fetch_trace.py <trace_id> overview

This returns metadata (status, duration, tokens, model) and summaries (request, answer preview, tool usage counts). Use this to orient yourself before going deeper.

2. Explore steps or LLM calls as needed

Depending on the user's question, drill into the relevant data:

User wants to know... Command
What tools were called and in what order steps [start] [count]
Full input/output of a specific tool call step <N>
How many LLM calls and their token costs llm-calls [start] [count]
What messages were sent to Claude in a specific turn llm-call <N>
Just the final result answer

3. Handle long content with segmented reads

When content is large, the script automatically segments output to ~4000 characters. If you see a [CONTINUED: ...] message at the end of output, call the command shown in that message to read the next segment. Repeat until all content is read.

Example sequence:

python scripts/fetch_trace.py <id> step 5
# Output ends with: [CONTINUED: use 'step 5 --offset 4000' for next segment]

python scripts/fetch_trace.py <id> step 5 --offset 4000
# Output ends with: [CONTINUED: use 'step 5 --offset 8000' for next segment]

python scripts/fetch_trace.py <id> step 5 --offset 8000
# Full content now read

Command Reference

Mode Syntax Description
overview fetch_trace.py <id> overview Metadata + summary stats
steps fetch_trace.py <id> steps [start] [count] Paginated step list (default: 30/page)
step fetch_trace.py <id> step <N> [--offset <chars>] Single step full content
llm-calls fetch_trace.py <id> llm-calls [start] [count] Paginated LLM call list
llm-call fetch_trace.py <id> llm-call <N> [--offset <chars>] Single LLM call full content
answer fetch_trace.py <id> answer Final answer only

Read the full file on GitHub · 81 lines

Files

What ships with it

1 file 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.

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 · 81 lines · 72 tokens per session scan A d7dd643eabb6

Subscribe to this mod's changes

trace-qa is a skill published in the GitHub repository dp-archive/archive (1,105 stars, last pushed 6mo ago), licensed Apache-2.0. It adds 72 tokens to every session and 803 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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