concurrency-verifier

concurrency-verifier is an agent for Claude Code from berrzebb/quorum. It costs 42 tokens per session (320 once invoked), scanned A, original, MIT.

A source-code reviewer for asynchronous programs, where multiple operations can run at the same time. It looks for unsafe shared-state access, race conditions, and possible deadlocks—situations where work waits forever.

In plain words
What is it for?
Use it to inspect Promise.all usage, workers, shared state, locks, dependency relationships, and related asynchronous coordination.
Why use it?
It helps identify bugs caused by operations finishing in an unexpected order or blocking one another. It focuses on concurrency safety rather than application behavior.

Agent for Claude Code

Written for Claude Code: allowed-tools in frontmatter. Also seen: model in frontmatter; mentions Claude Code.

Installs and runs on its own, but its text points at files inside its plugin — anything it tells you to read at a ${CLAUDE_PLUGIN_ROOT} path is only there once the plugin is installed. Installing the plugin gets both.

Part of the quorum plugin — 10 commands, 13 agents shipped together

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.

agentmods
npx agentmods add agents/berrzebb/quorum/concurrency-verifier
Clone the repo
git clone --depth 1 https://github.com/berrzebb/quorum

Made for: Claude Code.

Or install quorum, the plugin that ships this one along with the rest of its 10 commands, 13 agents.

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 concurrency-verifier

README.md
[![agentmods](https://agentmods.dev/badge/agents/berrzebb/quorum/concurrency-verifier.svg)](https://agentmods.dev/agents/berrzebb/quorum/concurrency-verifier)
Your own site
<a href="https://agentmods.dev/agents/berrzebb/quorum/concurrency-verifier"><img src="https://agentmods.dev/badge/agents/berrzebb/quorum/concurrency-verifier.svg" alt="Measured on agentmods" height="20"></a>
Per session 42 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 320 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00042 $0.00320
Opus 5 $0.00021 $0.00160
Sonnet 5 $0.00008 $0.00064
Haiku 4.5 $0.00004 $0.00032

Measured 5d ago against content hash ab7c1b5807ea, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-05, from the pricing page.

Security

Grade A, and why

concurrency-verifier 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 5d 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.

platform/adapters/claude-code/agents/concurrency-verifier.md · 36 lines

What it actually says

Concurrency Verifier (Claude Code)

Read and follow:

  • Base protocol: ${CLAUDE_PLUGIN_ROOT}/../../../agents/knowledge/specialist-base.md
  • Domain knowledge: ${CLAUDE_PLUGIN_ROOT}/../../../agents/knowledge/domains/concurrency.md

Claude Code Tool Invocation

node "${CLAUDE_PLUGIN_ROOT}/../../core/tools/tool-runner.mjs" dependency_graph --path src/
node "${CLAUDE_PLUGIN_ROOT}/../../core/tools/tool-runner.mjs" code_map --path src/
node "${CLAUDE_PLUGIN_ROOT}/../../core/tools/tool-runner.mjs" audit_scan --pattern all

Domain-Specific Anti-Patterns

  • Do NOT review business logic — focus only on concurrency safety
  • Do NOT flag single-threaded code for concurrency issues
  • Do NOT assume locking semantics without reading the lock implementation
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. 5d ago First seen · 36 lines · 42 tokens per session scan A ab7c1b5807ea

Subscribe to this mod's changes

concurrency-verifier is an agent published in the GitHub repository berrzebb/quorum (10 stars, last pushed 4mo ago), licensed MIT. It adds 42 tokens to every session and 320 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 2026-08-31.