What is codex-usage-heatmap?

A local tool for reading Codex usage logs and turning token-use data into GitHub-style heatmap reports. It avoids including prompts, responses, credentials, or raw logs in reports.

Use it to add support for new log formats, debug missing usage, test parsers, and build or verify the heatmap project.

It helps you inspect usage while keeping sensitive local data private and avoiding assumptions about changing log formats.

How Gatsby007max/codex-usage-heatmap configures Claude Code and Codex

Reuse

Borrowing it

Nothing to install: this file belongs to Gatsby007max/codex-usage-heatmap. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/Gatsby007max/codex-usage-heatmap/main/.agents/skills/codex-usage-heatmap/SKILL.md

Clone the repo

git clone --depth 1 https://github.com/Gatsby007max/codex-usage-heatmap

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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/gatsby007max/codex-usage-heatmap/codex-usage-heatmap/github.svg)](https://agentmods.dev/skills/gatsby007max/codex-usage-heatmap/codex-usage-heatmap)

Your own site

<a href="https://agentmods.dev/skills/gatsby007max/codex-usage-heatmap/codex-usage-heatmap"><img src="https://agentmods.dev/badge/skills/gatsby007max/codex-usage-heatmap/codex-usage-heatmap/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.

Your own site · 80×15

<a href="https://agentmods.dev/skills/gatsby007max/codex-usage-heatmap/codex-usage-heatmap"><img src="https://agentmods.dev/badge/skills/gatsby007max/codex-usage-heatmap/codex-usage-heatmap.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 77 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 523 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 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.

Model	Per session	Once invoked
Fable 5.1	$0.00077	$0.00523
Opus 5.5	$0.00031	$0.00209
Sonnet 5.5	$0.00015	$0.00105
Haiku 4.5	$0.00008	$0.00052

Measured 2mo ago against content hash 00bf1142b2f8, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

codex-usage-heatmap 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 2mo ago.

The scan reads SKILL.md. This mod also ships 2 executable files (scripts/generate-sample.sh, scripts/verify.sh), 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.

.agents/skills/codex-usage-heatmap/SKILL.md · 71 lines

What it actually says

Codex Usage Heatmap Skill

Purpose

Help maintain, debug, extend, release, and operate the codex-usage-heatmap project safely.

Non-negotiable Rules

Never read or print auth.json, API keys, refresh tokens, access tokens, cookies, .env values, private keys, or credentials.
Never include prompt text or model response text in generated reports.
Never store raw logs.
Treat Codex local log schemas as unstable.
Prefer parser adapters and sanitized fixtures over hard-coded assumptions.
Keep the tool local-only by default.
Do not add network calls unless explicitly requested and documentation is updated.
Keep all public repository content English-only.
Before completing code changes, run:
- pnpm lint
- pnpm typecheck
- pnpm test
- pnpm build
- pnpm check:language

Common Workflows

Add Support for a New Codex Log Shape

Add a sanitized fixture under fixtures/.
Add or update a parser adapter in src/parsers/.
Normalize into NormalizedUsageEvent.
Add tests for:
- valid event
- missing timestamp
- malformed line
- no prompt or response leakage
- no credential leakage
Run verification commands.

Debug Missing Usage

Run pnpm dev doctor.
Confirm discovered paths.
Confirm readable JSONL count.
Confirm usage event count.
Inspect only keys and metadata, not message content.
Add a sanitized fixture for the observed structure if safe.

Prepare a Release

Run full checks.
Generate sample report.
Confirm README commands work.
Confirm no generated report contains local absolute paths by default.
Confirm npm package files are limited using package.json files.
Update CHANGELOG.md if needed.

Output Format for Codex

When making changes to this project, summarize:

changed files
tests run
privacy/security impact
known limitations
follow-up recommendations

Files

What ships with it

6 files 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.

2mo ago First seen · 71 lines · 77 tokens per session scan A 00bf1142b2f8

Subscribe to this mod's changes

codex-usage-heatmap is a skill published in the GitHub repository Gatsby007max/codex-usage-heatmap (1 stars, last pushed 5mo ago), licensed MIT. It adds 77 tokens to every session and 523 once invoked, about $0.0003 per session on Opus 5.5. 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 2026-08-31.

Analytics and metrics cli codex codex-cli developer-tools github-contributions heatmap

codex-usage-heatmap next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
codex-usage-heatmapGatsby007max/codex-usage-heatmap	Skill	1	5mo ago	MIT	A	77	Claude Code, Codex
fast-resumeangristan/fast-resume	Skill	190	yesterday	MIT	A	50	Claude Code, Codex
promo-video-pipelinerexleimo/aios	Skill	62	yesterday	MIT	A	92	Claude Code, Codex
model-routerrexleimo/aios	Skill	62	yesterday	MIT	A	60	Claude Code, Codex
rexai-image-generationrexleimo/aios	Skill	62	yesterday	MIT	A	80	Codex
verification-looprexleimo/aios	Skill	62	yesterday	MIT	A	32	Claude Code, Codex
aios-offload-recallrexleimo/aios	Skill	62	yesterday	MIT	A	34	Claude Code, Codex

codex-usage-heatmap: Skill for Claude Code