why

A session-audit tool for examining the latest Claude Code work session, including token use, repeated file reads, and tool-call costs.

In plain words
What is it for?
It is for investigating high token usage, low code output, duplicated reads, or the possible savings from Sipcode optimizers.
Why use it?
It shows where the session spent tokens and identifies waste that may be hidden in a long conversation.

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/anuj7411/sipcode/why
Any agent
npx skills add Anuj7411/sipcode --skill why
Clone the repo
git clone --depth 1 https://github.com/Anuj7411/sipcode

Made for: Claude Code, Codex.

Per session 90 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 327 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 $0.00090 $0.00327
Opus 5 $0.00045 $0.00163
Sonnet 5 $0.00018 $0.00065
Haiku 4.5 $0.00009 $0.00033

Measured 2d ago against content hash cbdf906dd563, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

why 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 2d 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.

skills/why/SKILL.md · 18 lines

What it actually says

Sipcode — Why (session forensics)

Call the sipcode:audit_latest_session MCP tool to produce a forensic report of the user's most recent Claude Code session.

If the user provides a session ID prefix (e.g., "audit session 3bca35e2"), pass it as the session_id argument. Otherwise, omit and the tool will pick the most recent session across all projects.

When presenting the result:

  • Lead with the output ratio (the percentage of total tokens that were actual code output). 0.3–2% is typical.
  • Surface the top 3 leaks with their dollar cost.
  • The "Sipcode estimates ~X tokens were RECOVERABLE" line is potential, not realized. Only realized after sipcode rules --install + new sessions + sipcode impact. Be explicit about this when relaying the number.
  • If the session is unusually large (> $10) or unusually wasteful (output ratio < 0.2%), call that out.

Do NOT extrapolate the single-session savings across many sessions. Each session is its own forensic snapshot.

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. 2d ago First seen · 18 lines · 90 tokens per session scan A cbdf906dd563

Subscribe to this mod's changes

why is a skill published in the GitHub repository Anuj7411/sipcode (46 stars, last pushed 1mo ago), licensed MIT. It adds 90 tokens to every session and 327 once invoked, about $0.0005 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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