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 agentmods add skills/v0idos/performance-deity/concurrencynpx skills add v0idOS/performance-deity --skill concurrencygit clone --depth 1 https://github.com/v0idOS/performance-deityWrote 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/v0idos/performance-deity/concurrency)<a href="https://agentmods.dev/skills/v0idos/performance-deity/concurrency"><img src="https://agentmods.dev/badge/skills/v0idos/performance-deity/concurrency.svg" alt="Measured on agentmods" 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 | $0.00028 | $0.00319 |
| Opus 5 | $0.00014 | $0.00160 |
| Sonnet 5 | $0.00006 | $0.00064 |
| Haiku 4.5 | $0.00003 | $0.00032 |
Grade A, and why
concurrency 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 4d 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.
What it actually says
Execute all four phases in order.
Phase 1 — Chaos Script
Write a test that fires ≥1,000 concurrent async requests or threads at the target function simultaneously. The test must assert the final state deterministically (e.g. if a counter is incremented 1,000 times, assert counter === 1000).
Phase 2 — Failure Verification
Run the test. If it passes consistently:
- Increase concurrency to 10,000.
- Add
sleep()calls mid-execution to force thread context switching.
Prove the function is unsafe before fixing it. Do not add synchronization to code that has not been shown to fail.
Phase 3 — Synchronization
Implement the minimal synchronization primitive needed (prefer in this order):
- Atomic operations (e.g.
Atomics.add,atomic.AddInt64,std::atomic) - Mutex / Lock with the smallest possible critical section
- Semaphore only if mutual exclusion alone is insufficient
Do not hold a lock across any I/O operation.
Phase 4 — Report
Re-run the test with 10,000 concurrent requests. Report the pass/fail counts.
| Metric | Before | After |
|---|---|---|
| Failures at 1k concurrent | N | 0 |
| Failures at 10k concurrent | N | 0 |
The target is 0 failures.
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.
- 4d ago First seen · 38 lines · 28 tokens per session scan A 7e39dc5a2be8
concurrency is a skill published in the GitHub repository v0idOS/performance-deity (2 stars, last pushed 4mo ago), licensed MIT. It adds 28 tokens to every session and 319 once invoked, about $0.0001 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 2026-08-31.
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