LifeOS is an AI-assisted personal operating system that records a person’s goals, values, context, and current situation to help move them toward a desired future state. It supports work such as building applications, starting businesses, and creative projects. Its catalogue entries extend the system through skills, hooks, agents, and commands.
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.
npx skills add danielmiessler/LifeOS --skill developmentgit clone --depth 1 https://github.com/danielmiessler/LifeOSWrote 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.
[](https://agentmods.dev/skills/danielmiessler/lifeos/development)<a href="https://agentmods.dev/skills/danielmiessler/lifeos/development"><img src="https://agentmods.dev/badge/skills/danielmiessler/lifeos/development/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.
<a href="https://agentmods.dev/skills/danielmiessler/lifeos/development"><img src="https://agentmods.dev/badge/skills/danielmiessler/lifeos/development.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00000 | $0.03559 |
| Opus 5.5 | $0.00000 | $0.01424 |
| Sonnet 5.5 | $0.00000 | $0.00712 |
| Haiku 4.5 | $0.00000 | $0.00356 |
Grade A, and why
Development 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.
How it starts
The opening of the file, as written. The whole thing — 120 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Development
Contents: Ideal State · Intent Routing · Data & Config · Acceptance (output contract) · Safety gates · Execution · Tools · Gotchas · Examples
The thin actor between an ISA and its code. The ISA holds the rigor: what done means, every criterion, every criterion's eval. Assay is how each criterion is verified, and the only eval system a build may use (LIFEOS/DOCUMENTATION/Assay/AssaySystem.md § One eval system), at the cheapest honest tier: a code assert when the criterion is literal, a judgment-layer question when it needs reading, a judge only when neither can answer, the principal for taste. Development builds, tests and modifies until the code and the ISA agree.
Ideal State
- At the end of every run the code and its ISA agree: every criterion in scope carries an eval at the cheapest honest Assay tier, and its result is recorded in the ISA.
- Criteria change before the code they govern; only a trivial change (a typo, a value, an obvious one-liner) skips the ISA.
- Nothing the principal will see or use is called done until acceptance against a reference they approved has passed (§ Acceptance); passing tests are the builder's signal, not the done signal.
- The report on such work opens with the acceptance verdict and its capture paths. The captures show the whole thing working the way the principal meets it: a page renders top to bottom at desktop and phone widths and looks like the reference. A report without a passing verdict, and without the principal's waiver, does not call the work done, fixed or shipped.
- The criteria are the only artifact written before the code.
- Nothing here deploys or writes production data; the project's gated deploy command ships.
Intent Routing
| Intent | Trigger | File |
|---|---|---|
| Build | new app, new feature, "build this", an existing repo with no ISA | Intents/Build.md |
| Test | "test the app", "is it in sync", "run the evals", a check before deploy | Intents/Test.md |
| Modify | change, fix or remove behavior in an app that has an ISA | Intents/Modify.md |
| Checkup | "health check", "checkup", "why are these ISCs red", "get everything in sync", "audit the ISA" | Intents/Checkup.md |
What ships with it
12 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.
- Intents/Build.md 4.9 KB
- Intents/Checkup.md 9.3 KB
- Intents/Modify.md 3.6 KB
- Intents/Test.md 4.4 KB
- References/Guards.md 2.1 KB
- References/Inventory.md 953 B
- References/Sizing.md 636 B
- References/Tools.md 3.8 KB
- Tools/Checkup.help.md 1.0 KB
- Tools/Checkup.ts 11 KB runs code
- Tools/Inventory.ts 14 KB runs code
- Tools/IsaCheck.ts 19 KB runs code
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.
- 2d ago First seen · 120 lines · 0 tokens per session scan A 726848c96940
Development is a skill published in the GitHub repository danielmiessler/LifeOS (19,637 stars, last pushed 2d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 3,559 tokens. 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 2026-10-28.
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Carrying complex coding and project work through commands that take minutes or hours: evals, benchmarks, full builds and test suites, migrations, servers, multi-round runs. Use when a command may run past a few minutes, timed out once, or when the task spans several rounds of run, read results, fix, run again.
superpowers
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tdd
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