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 antithesishq/antithesis-skills --skill antithesis-debuggit clone --depth 1 https://github.com/antithesishq/antithesis-skillsWrote 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/antithesishq/antithesis-skills/antithesis-debug)<a href="https://agentmods.dev/skills/antithesishq/antithesis-skills/antithesis-debug"><img src="https://agentmods.dev/badge/skills/antithesishq/antithesis-skills/antithesis-debug/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/antithesishq/antithesis-skills/antithesis-debug"><img src="https://agentmods.dev/badge/skills/antithesishq/antithesis-skills/antithesis-debug.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk warn
- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to medium
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- medium Prompt Injection · line 58 Large whitespace padding was detected (a block of blank lines or a long run of spaces). This can push injected instructions below or to the right of the visible area so a human reviewer never sees them while the agent still reads them. Manual review of the hidden content is recommended.Fix: Remove the large whitespace padding (blank-line blocks or long space runs) and review any content hidden below or to the right of it. Keep skill files compact and reviewable so no instructions can be
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 | $0.00048 | $0.03014 |
| Opus 5 | $0.00024 | $0.01507 |
| Sonnet 5 | $0.00010 | $0.00603 |
| Haiku 4.5 | $0.00005 | $0.00301 |
Grade A, and why
antithesis-debug scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 304 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Antithesis Multiverse Debugger
Skill version: 2026-09-08 2e4a837
Use the agent-browser skill to interact with the Antithesis multiverse
debugger.
Every debugging session should use:
- a fresh, unique
SESSIONvalue such asantithesis-debug-$(date +%s)-$$
Use --session-name antithesis so agent-browser manages shared
authentication state automatically, while --session "$SESSION" keeps each
debugging run isolated from other concurrent agents. Close the unique live
session when debugging is complete.
When to use this skill
Use this when:
- the user gives an Antithesis debugging-session URL
- the user makes a request to inspect container filesystem, runtime state, or events inside Antithesis
- the triage skill has launched an MVD session when investigating the results of a run
For auth and report navigation, use the antithesis-agent-browser skill. It
owns the agent-browser session and authentication flow. This skill handles
the debugger itself.
Prerequisites
- DO NOT PROCEED if
agent-browseris not installed. Seehttps://raw.githubusercontent.com/vercel-labs/agent-browser/refs/heads/main/README.mdfor installation options. - DO NOT PROCEED if
agent-browseris older than versionv0.23.4. You can upgrade withagent-browser upgrade.
Gathering user input
Before starting, collect the following from the user:
- Debugger URL (required) — A debugging-session URL like
https://TENANT.antithesis.com/debugging-session/.... - What to investigate — Are we checking filesystem contents? Runtime state? Specific artifacts?
- Container name (if known) — The name of the container to target. If not provided, the log view or container dropdown will show available containers.
Simplified vs. advanced mode
The debugger has two modes. Prefer simplified mode — it is sufficient for most tasks.
| Mode | Best for | How it works |
|---|---|---|
| Simplified | Running shell commands, reading files, listing directories, extracting artifacts | Click log lines to set moment/container, type bash commands, press Send |
| Advanced | Programmatic inspection, branching, event sets, custom JavaScript, multi-step notebook workflows | Monaco editor with JavaScript cells, action authorization, runtime API |
What ships with it
10 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.
- assets/antithesis-debug.js 29 KB runs code
- assets/download-mvd-log.sh 5.1 KB runs code
- assets/process-logs.py 46 KB runs code
- references/actions.md 5.3 KB
- references/advanced-debugger.md 19 KB
- references/common-inspections.md 8.9 KB
- references/download-log.md 4.0 KB
- references/notebook.md 6.0 KB
- references/setup-session.md 6.1 KB
- references/simplified-debugger.md 15 KB
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.
- yesterday Changed 6f15b7a381fd
- 6d ago Changed a9692021c4bf
- 10d ago First seen · 304 lines · 48 tokens per session scan A c844dd998c58
antithesis-debug is a skill published in the GitHub repository antithesishq/antithesis-skills (267 stars, last pushed yesterday), licensed Apache-2.0. It adds 48 tokens to every session and 3,014 once invoked, about $0.0002 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.
Other skills, from other repositories
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experimental-code-coverage-local-debugger
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adversarial-reviewer
Adversarial code review that assumes bugs exist and hunts for them. Use when asked to review code, find bugs, audit for correctness, stress-test a PR, or when someone says "tear this apart" or "what's wrong with this". Give no benefit of the doubt — every line is guilty until proven innocent.
cli-e2e
Write, modify, or debug Docker-based Composio CLI end-to-end tests under ts/e2e-tests/cli, including binary invocation, fixture isolation, output assertions, and package manifests. Use for CLI E2E test suites only; use cli-command for CLI source implementation.
work
Deliver one maintainer-approved EmDash issue, choosing the bug-fix path for a defect and the direct implementation path for an enhancement or task.