Assess race conditions, transactional invariants, idempotency, retries, replay, rate and quota enforcement, algorithmic complexity, resource amplification, and cost abuse during authorized…
$ npx skills add cyberful/cyberful --skill test-concurrency-resource-abuse -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install cyberful/cyberful test-concurrency-resource-abuse --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/cyberful/cyberful.git skills-src && mkdir -p .claude/skills && cp -r skills-src/cyberful/builtin/skills/test-concurrency-resource-abuse .claude/skills/test-concurrency-resource-abuse && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "test-concurrency-resource-abuse" agent skill from https://github.com/cyberful/cyberful/tree/main/cyberful/builtin/skills/test-concurrency-resource-abuse into .claude/skills/test-concurrency-resource-abuse/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "test-concurrency-resource-abuse", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/cyberful/cyberful/tree/main/cyberful/builtin/skills/test-concurrency-resource-abuseType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add cyberful/cyberful --skill test-concurrency-resource-abuse -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install cyberful/cyberful test-concurrency-resource-abuse --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/cyberful/cyberful.git skills-src && mkdir -p .agents/skills && cp -r skills-src/cyberful/builtin/skills/test-concurrency-resource-abuse .agents/skills/test-concurrency-resource-abuse && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "test-concurrency-resource-abuse" agent skill from https://github.com/cyberful/cyberful/tree/main/cyberful/builtin/skills/test-concurrency-resource-abuse into .agents/skills/test-concurrency-resource-abuse/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "test-concurrency-resource-abuse", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add cyberful/cyberful --skill test-concurrency-resource-abuse -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install cyberful/cyberful test-concurrency-resource-abuse --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/cyberful/cyberful.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/cyberful/builtin/skills/test-concurrency-resource-abuse .cursor/skills/test-concurrency-resource-abuse && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "test-concurrency-resource-abuse" agent skill from https://github.com/cyberful/cyberful/tree/main/cyberful/builtin/skills/test-concurrency-resource-abuse into .cursor/skills/test-concurrency-resource-abuse/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "test-concurrency-resource-abuse", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/cyberful/cyberful.git --path cyberful/builtin/skills/test-concurrency-resource-abuse--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add cyberful/cyberful --skill test-concurrency-resource-abuse -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install cyberful/cyberful test-concurrency-resource-abuse --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/cyberful/cyberful.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/cyberful/builtin/skills/test-concurrency-resource-abuse .gemini/skills/test-concurrency-resource-abuse && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "test-concurrency-resource-abuse" agent skill from https://github.com/cyberful/cyberful/tree/main/cyberful/builtin/skills/test-concurrency-resource-abuse into .gemini/skills/test-concurrency-resource-abuse/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "test-concurrency-resource-abuse", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install cyberful/cyberful test-concurrency-resource-abuseInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add cyberful/cyberful --skill test-concurrency-resource-abuse -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/cyberful/cyberful.git skills-src && mkdir -p .github/skills && cp -r skills-src/cyberful/builtin/skills/test-concurrency-resource-abuse .github/skills/test-concurrency-resource-abuse && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "test-concurrency-resource-abuse" agent skill from https://github.com/cyberful/cyberful/tree/main/cyberful/builtin/skills/test-concurrency-resource-abuse into .github/skills/test-concurrency-resource-abuse/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "test-concurrency-resource-abuse", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add cyberful/cyberful --skill test-concurrency-resource-abuse -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install cyberful/cyberful test-concurrency-resource-abuse --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/cyberful/cyberful.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/cyberful/builtin/skills/test-concurrency-resource-abuse .opencode/skills/test-concurrency-resource-abuse && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "test-concurrency-resource-abuse" agent skill from https://github.com/cyberful/cyberful/tree/main/cyberful/builtin/skills/test-concurrency-resource-abuse into .opencode/skills/test-concurrency-resource-abuse/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "test-concurrency-resource-abuse", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
test-concurrency-resource-abuseAssess race conditions, transactional invariants, idempotency, retries, replay, rate and quota enforcement, algorithmic complexity, resource amplification, and cost abuse during authorized…
Test Concurrency Resource Abuse is an agent skill from cyberful/cyberful. Assess race conditions, transactional invariants, idempotency, retries, replay, rate and quota enforcement, algorithmic complexity, resource amplification, and cost abuse during authorized penetration tests or code audits. Use for TOCTOU, double spend, duplicate redemption, limit bypass, ReDoS, decompression bombs, fan-out, pagination, batch, queue, storage, compute, and unbounded-consumption risks.
Its SKILL.md is about 1.1k tokens, which your agent loads only when the skill is triggered. The skill folder holds 14 other files, including scripts, reference files and assets (for example `agents/openai.yaml`, `assets/concurrency-evidence.schema.json` and `assets/concurrency-probe.example.json`).
It sits in Development, covering Async programming. The repository describes itself as: Cyberful is an open-source AI Red Team for discovering, exploiting, verifying, and remediating vulnerabilities. The licence is AGPL-3.0.
6 steps, taken from the first numbered list in SKILL.md.
Read from SKILL.md and the folder at commit ec598a6. It shows what the files ask for, not the result of running them.
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Ships 2 files in scripts/ (Python), which the agent can run.
From the folder's file list and the shell code blocks in SKILL.md.
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Test Concurrency Resource Abuse loads about 1.1k tokens when it runs, and up to ~2.2k if it reads all its reference files. Until then it costs about 109 tokens; SKILL.md has 431 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
The automated check found no risky patterns in SKILL.md.
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); the scripts in this folder are not scanned.
The full file from cyberful/cyberful at commit ec598a6, republished under its AGPL-3.0 licence (© cyberful). 431 words, ~1,131 tokens.
.claude/skills/test-concurrency-resource-abuse/SKILL.md (or your agent's skills folder). This skill also uses 9 other files; get the full folder from GitHub.Write the invariant before generating load: one redemption per entitlement, nonnegative balance, one active primary owner, monotonic state, bounded work per principal, or finite cost per request.
Map every authority that reads or writes it: API handler, database, cache, queue, worker, payment processor, scheduler, webhook, and reconciliation job. Record transaction boundaries, isolation level, uniqueness constraints, locks, compare-and-swap, idempotency stores, retries, and timeout semantics.
Read race-idempotency.md for state races. Read resource-amplification.md for rate, complexity, and cost review.
Success is an invariant violation, not merely two successful HTTP responses. Use single-digit concurrency first; precision exposes more than indiscriminate load.
For repeatable active trials in Pentest or Bug Bounty, stage scripts/run_concurrency_probe.py, its manifest, and the probe example. Declare canonical allowed origins plus request and concurrency limits before execution. Literal loopback targets connect directly. Docker service hostnames and other non-loopback targets must use Cyberful's runtime-injected HTTP_PROXY or HTTPS_PROXY; optional trust comes only from runtime SSL_CERT_FILE or CURL_CA_BUNDLE, and TLS verification is never disabled. Secret authorization is accepted only through CYBERFUL_PROBE_AUTHORIZATION. The JSON payload cannot select the route or trust source, and the script is unavailable for Code Audit target traffic. It writes raw bounded responses under the evidence schema; reconcile durable state separately because response success alone never establishes an invariant violation.
Follow an operation across client retries, gateway retries, queue redelivery, worker crashes, webhook duplication, provider callbacks, and reconciliation. Determine whether the idempotency key is bound to principal, operation, canonical payload, and retention window.
Test same key/different payload, different key/same semantic operation, timeout-before-response, commit-before-crash, and stale replay after state transition.
Express cost as a function of controlled input: CPU, memory, database reads or writes, outbound calls, queue items, object count, bytes stored, response bytes, or paid third-party spend. Look for superlinear growth, recursive fan-out, and work performed before authentication, quota, or deduplication.
Rate limits must be evaluated across distributed nodes, alternate endpoints, identities, tenants, IPv4/IPv6, batch sizes, and asynchronous continuations.
Include initial state, synchronized sequence, durable final state, externally visible effects, required concurrency, consistency window, and resource cost. Recommend database-enforced invariants, atomic state transitions, bounded work, admission control, and correctly scoped idempotency.
© cyberful, AGPL-3.0. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file
SKILL.md and 9 other files (scripts, references, assets) in cyberful/builtin/skills/test-concurrency-resource-abuse of cyberful/cyberful.
Open the folder on GitHubat commit ec598a6
Test Concurrency Resource Abuse next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Test Concurrency Resource Abuse this skillcyberful/cyberful | 135 | — | ~1.1k | Automated safety check: Pass | AGPL-3.0 | |
| Swift Concurrency PerformanceLivsy90/iOS-Performance-Agent-Skills | 117 | — | ~2.9k | Automated safety check: Pass | MIT | |
| YugabyteDB ASH Instrumentationyugabyte/yugabyte-db | 11k | — | ~4.5k | Automated safety check: Pass | Custom licence | |
| Mirage VFS Adapter Authoringstrukto-ai/mirage | 3.7k | — | ~2.4k | Automated safety check: Pass | Apache-2.0 | |
| Golang Patternsantoniopaya22/go-rest-template | 172 | 9 repos | ~3.5k | Automated safety check: Pass | None | |
| Rust Async Patternsdiodeme/Gold-Band | 143 | 10 repos | ~3.1k | Automated safety check: Pass | AGPL-3.0 |
Livsy90/iOS-Performance-Agent-Skills
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yugabyte/yugabyte-db
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strukto-ai/mirage
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antoniopaya22/go-rest-template
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diodeme/Gold-Band
Master Rust async programming with Tokio, async traits, error handling, and concurrent patterns.
henrypldev/react-native-nitro-mlx
Diagnose Swift Concurrency issues, refactor callback-based code to async/await, and guide Swift 6 migration when working with tasks, actors, @MainActor, Sendable, data races, thread safety, or…
cyberful/cyberful
Audit infrastructure-as-code artifacts for unsafe defaults, policy gaps, privilege exposure, control drift, and deployment-impact evidence.
cyberful/cyberful
Audit Kubernetes admission and policy-as-code enforcement against local workload manifests, exception paths, namespace scope, and deployment evidence.
cyberful/cyberful
Audit PCI DSS penetration-test methodology, scope, internal and external reports, segmentation results, tester independence, remediation, retesting, retention, and multi-tenant support evidence.
cyberful/cyberful
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cyberful/cyberful
Build a high-fidelity network and service inventory using Nmap, Masscan, packet capture, DNS, and protocol-specific follow-up.
cyberful/cyberful
Operate Semgrep and source-oriented static analysis as a hypothesis, coverage, and regression system during advanced code audits.
Categories
Assess race conditions, transactional invariants, idempotency, retries, replay, rate and quota enforcement, algorithmic complexity, resource amplification, and cost abuse during authorized…. Test Concurrency Resource Abuse is an agent skill from cyberful/cyberful. Assess race conditions, transactional invariants, idempotency, retries, replay, rate and quota enforcement, algorithmic complexity, resource amplification, and cost abuse during authorized penetration tests or code audits.
Test Concurrency Resource Abuse fits situations like: duplicate redemption; decompression bombs; unbounded-consumption risks.
Run `npx skills add cyberful/cyberful --skill test-concurrency-resource-abuse -a claude-code`. Or copy the skill folder (cyberful/builtin/skills/test-concurrency-resource-abuse in cyberful/cyberful) into .claude/skills/test-concurrency-resource-abuse in your project. Claude Code loads it when a task matches its description.
Run `npx skills add cyberful/cyberful --skill test-concurrency-resource-abuse -a codex`. Or copy the skill folder (cyberful/builtin/skills/test-concurrency-resource-abuse in cyberful/cyberful) into .agents/skills/test-concurrency-resource-abuse in your project. Codex loads it when a task matches its description.
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add cyberful/cyberful --skill test-concurrency-resource-abuse -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/test-concurrency-resource-abuse, .gemini/skills/test-concurrency-resource-abuse, .github/skills/test-concurrency-resource-abuse and .opencode/skills/test-concurrency-resource-abuse in your project.
Going by SKILL.md and its folder, Test Concurrency Resource Abuse needs Python for the scripts in its folder. Our summary lists: Python 3; Docker.
SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.
Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. The check reads SKILL.md only: the scripts in the folder are not scanned, so read them before running anything.
Test Concurrency Resource Abuse is published under the AGPL-3.0 licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.
About 1.1k tokens (SKILL.md is roughly 4.5k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full. Its references folder adds about 1.1k tokens, read only when the agent opens those files.
Skills that share tags, products or a category with Test Concurrency Resource Abuse: Swift Concurrency Performance (Livsy90/iOS-Performance-Agent-Skills, 117 stars), YugabyteDB ASH Instrumentation (yugabyte/yugabyte-db, 11k stars), Mirage VFS Adapter Authoring (strukto-ai/mirage, 3.7k stars) and Golang Patterns (antoniopaya22/go-rest-template, 172 stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
cyberful (a GitHub organization) maintains it in cyberful/cyberful, which has 135 GitHub stars. The repository holds 85 skills in this directory. The repository was last updated on August 24, 2026.
Source: cyberful/cyberful on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.
