Sipcode

Sipcode

Keep Claude Code's context clean for sharper answers and lower cost, automatically.

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Install in 30 seconds

npm i -g sipcode

sipcode init

That is it. Your next Claude Code session will use Sipcode automatically. Verify a few minutes later:

sipcode drift

If the output reads no drift, context health stable, Sipcode is doing its job.

Already installed? Keep it fresh. Sipcode makes zero network calls, so it can't pop an "update available" notice. Build a weekly habit: run sipcode update (or npm i -g sipcode@latest) to pull the latest fixes. Full details in Updating Sipcode.

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What is Sipcode?

Sipcode is a free command-line tool that sits between you and Claude Code. It does three things:

1. It watches Claude Code's context window and warns you when it starts to bloat (we call this "context rot")
2. It catches duplicate file reads and other waste before they reach Claude, so you pay less for the same answers
3. It gives you receipts. Every saving is measurable in your terminal.

It is open source under the MIT license. It makes zero network calls during normal use. Your data never leaves your laptop.

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How Sipcode compares

Sipcode is complementary to memory tools that persist context across sessions (Tool A in the table). Sipcode keeps each individual session clean. They solve different problems. Run both for maximum effect.

Full feature-by-feature comparison with tool names revealed: anuj7411.github.io/sipcode/compare

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Why you probably want it

If you use Claude Code for real work, you have already felt this:

• Long sessions get expensive fast. A two-hour session on Claude Max can burn through your daily plan
• Quality drops as the context window fills. Claude starts re-reading files, repeating itself, losing the thread of what you asked
• You cannot tell what is bloat and what is signal

Sipcode measures the bloat, then removes the parts Claude does not need. Run sipcode benchmark on any machine and you will see the same 62.6% median reduction on the locked 20-task corpus. That corpus is synthetic: scripted pairs of Claude Code transcripts (without and with Sipcode), not recordings of live sessions. It shows what Sipcode's mechanisms remove from a modeled session. Your own number depends on your workload, and sipcode impact measures it on your real sessions.

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The two-minute tour

After installing, here are the five commands that show you what Sipcode is doing.

1. sipcode drift

Tells you if your current Claude Code session is drifting from your normal usage pattern. Bloated context, repeated reads, stale signals are all flagged here.

✓ Sipcode drift: no drift, context health stable vs your recent baseline.

By default it checks your most recent session, across Claude Code and Codex. --session checks a specific one, --here limits it to sessions from the folder you are in, and --agent claude-code or --agent codex picks the tool.

2. sipcode proxy --stats

Shows what Sipcode caught in the current session, broken down by rewriter.

Sipcode proxy, rewrite stats

total rewrites: 144 est. tokens saved: ~288,685 (heuristic) signal kept: 67% (med), weighted across all rewrites

3. sipcode benchmark

Runs the locked 20-task corpus and produces a reproducible savings number. Anyone, anywhere can run this and get 62.6%. The transcripts are scripted, not recorded from live sessions, so read it as a model of Sipcode's mechanisms rather than a measured bill (see METHODOLOGY).

62.6%  median savings on a locked 20-task corpus

range 37.4% to 80.6% 3,567,170 tokens $22.48

4. sipcode today

Daily spend summary. Tokens used, sessions, output ratio, comparison to your 30-day median.

spend so far    $1.20    across 4 sessions

tokens so far 943.8K output ratio 3.7%

5. sipcode forecast

Month-end projection based on your last 14 days.

projected month-end   $17,674   (range $14,139 to $21,208)

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Codex

Sipcode also reads OpenAI Codex CLI session logs (~/.codex/sessions and ~/.codex/archived_sessions, or the folder CODEX_HOME points to). For Codex this is spend analytics and usage limits: Sipcode reports what your Codex sessions used, where the tokens went, and how close you are to your plan's limits. It does not change what Codex does.

Commands that read Codex: stats, today, forecast, trend, impact, why, receipt, drift, regress and limits (Codex only), plus the session tools in the MCP server (they take an optional agent input: "claude-code" or "codex") and get_codex_limits.

• --agent codex shows Codex only. --agent claude-code shows Claude Code only.
• With no --agent flag and both tools installed, stats, today, forecast, trend and impact print one section per tool. stats, today and forecast end with one combined line, in this shape:

  Both tools: <total tokens> tokens · ~$<Claude Code> + ~$<Codex>

• why, receipt and drift report on the most recent session across both tools. When the other tool has a recent session too, a one-line hint names it and the flag that shows it.
• --here works for Codex too: it matches the working folder Codex recorded for each session.
• --json covers one tool per call. Without --agent it covers Claude Code and prints a note on stderr when Codex logs exist too. Add --agent codex for Codex JSON.
• With no --agent flag on a machine with Cursor and Codex, Sipcode shows Codex (it does not read Cursor's session logs).

How Codex tokens are counted. Sipcode reads Codex's per-request usage records, or, in logs from older Codex versions, the change in the running total Codex logs after each request. Cached input is part of Codex's input count, so Sipcode never bills cached tokens twice. A request copied into a resumed or forked session file is counted once. On the maintainer's machine, Sipcode's per-file totals equal Codex's own final total_token_usage on all 15 real session logs, and an independent counter that shares no code with Sipcode (scripts/verify-counts.mjs) cross-checks every period command against the same logs.

Prices. Codex models are priced from OpenAI's API price table (developers.openai.com/api/docs/pricing, and each Codex model's page under developers.openai.com/api/docs/models, as of 2026-10-09), including the long-context rate for prompts over 272,000 input tokens. A model with no known price is shown as unpriced: its tokens are still counted, a line under the cost says how many were left out of it, and it is never shown as $0.

Not supported for Codex yet: writing rules to AGENTS.md (rules, and the rules step of init), registering the MCP server in Codex, the proxy and hooks (proxy, hygiene), estimate and benchmark. rules --agent codex and estimate --agent codex stop with error E009 instead of showing Claude Code data.

Compressed Codex logs. Codex compresses older session logs to .jsonl.zst. Sipcode reads them exactly like plain logs on Node.js 22.15 or newer. On an older Node.js it skips them, and every report starts with a warning that says how many it could not read and that reading them needs Node.js 22.15 or newer. A damaged or unreadable log gets the same kind of warning. With --json the warning is a note on stderr and the JSON is unchanged.

Codex limits: sipcode limits

Codex writes your plan's usage-limit readings into its own logs after each request. sipcode limits reads them, with zero network calls, and answers three questions: when will I hit my limit, what used it, and did it shrink.

Example output of sipcode limits --since all (the tokens-per-1% history here goes back further than the default 90 days):

sipcode limits · Codex · plan: go · as of 2h ago (your last Codex request)

Weekly limit 62% used resets Wed 14 Oct 14:00 at this pace: runs out Tue 13 Oct ~18:00 30-day limit 22% used resets Mon 2 Nov at this pace: lasts until reset

What used your weekly limit (since Wed 7 Oct) 0199a1b2-c3d4-7a11 sipcode 31% 3.1M tokens 0199a0f7-11aa-7b02 my-app 17% 1.4M tokens codex-auto-review (9 requests) 6% unattributed (no Codex requests on this computer) 8%

Tokens per 1% of your weekly limit (gpt-5.4) Mar 28: 425K Apr 1: 357K Apr 13: 77K Possible limit cut around Apr 13: 5.1x fewer tokens per 1%. Limits cover your whole account. Codex use on other devices or in the cloud is not in these logs and can look like a cut.

• Every limit window the logs report (5-hour, weekly, 30-day): percent used, reset time, and when it runs out at this pace. The pace is the percent used divided by the time since the period started, counted up to now, so the estimate moves later while you are not using Codex. "as of" is your last Codex request: the percent is only as fresh as that.
• What used it: the current period's top 5 sessions and projects (folder name only), plus Codex's automatic reviews as one line. Each rise in the percent is shared by the requests made since the previous rise, in proportion to their tokens. A rise with no request on this computer shows as unattributed, because limits are shared with your other devices and Codex cloud.
• Did it shrink: how many tokens 1% of the limit bought in each finished period with at least 20% used, compared only within one model (a period counts when 90% or more of its tokens came from one model). Periods that started