spike

spike is a skill for Claude Code, Codex from metaspartan/cybara. It costs 40 tokens per session (402 once invoked), scanned A, original, MIT.

A short, throwaway prototype used to answer whether a technical approach will work. Its result is a measured decision, not production code.

In plain words
What is it for?
Use it to test an unfamiliar API or library, compare approaches, or check a performance claim. It helps produce a viability verdict and recommendation.
Why use it?
It replaces guesswork with evidence before time is spent building the full solution.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it to test an unfamiliar API or library, compare approaches, or check a performance claim. It helps produce a viability verdict and recommendation.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/metaspartan/cybara/spike
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.

Any agent
npx skills add metaspartan/cybara --skill spike
Clone the repo
git clone --depth 1 https://github.com/metaspartan/cybara

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.

agentmods badge for spike

README.md
[![agentmods](https://agentmods.dev/badge/skills/metaspartan/cybara/spike/github.svg)](https://agentmods.dev/skills/metaspartan/cybara/spike)
Your own site
<a href="https://agentmods.dev/skills/metaspartan/cybara/spike"><img src="https://agentmods.dev/badge/skills/metaspartan/cybara/spike/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.

agentmods 80×15 button for spike

Your own site · 80×15
<a href="https://agentmods.dev/skills/metaspartan/cybara/spike"><img src="https://agentmods.dev/badge/skills/metaspartan/cybara/spike.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 40 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 402 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. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 5.1 $0.00040 $0.00402
Opus 5 $0.00020 $0.00201
Sonnet 5 $0.00008 $0.00080
Haiku 4.5 $0.00004 $0.00040

Measured 9d ago against content hash 26daab3652df, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

spike 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 9d 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/spike/SKILL.md · 35 lines

What it actually says

Spike

A spike is a time-boxed, throwaway investigation. Its output is a decision, not production code.

When to use

  • "Will approach X even work?" / "Can we do Y with Z?"
  • Comparing 2+ approaches and needing empirical data, not opinion.
  • De-risking an unknown (an API, a library, a perf claim) before building the real thing.

Procedure

  1. State the question precisely. What must be true for the approach to be viable? ("Can library X parse a 1GB file in <2s without OOM?")
  2. Set a time/effort box. Spikes are short — if it's taking long, narrow the question.
  3. Write the minimum code to answer the question. Use exec/write in an isolated scratch path (e.g. spike/). Don't worry about quality.
  4. Measure the actual thing. Run it; capture timing/output/errors. Don't extrapolate.
  5. Report a verdict:
    • Verdict: VIABLE / NOT VIABLE / NEEDS-MORE-INFO
    • Evidence: concrete numbers, snippet, or the failure mode observed.
    • Recommendation: proceed with X / avoid X because / next probe needed.
  6. Clean up the scratch code (or move it aside) unless it's promoted to real code.

Anti-patterns

  • Spending a spike polishing code instead of answering the question.
  • Reporting "it should work" without measuring.
  • Letting a spike silently become production code without a review pass.

Keep spikes honest: a "no, this won't work" verdict with evidence is a successful spike.

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. 9d ago First seen · 35 lines · 40 tokens per session scan A 26daab3652df

Subscribe to this mod's changes

spike is a skill published in the GitHub repository metaspartan/cybara (30 stars, last pushed yesterday), licensed MIT. It adds 40 tokens to every session and 402 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 2026-09-03.