Borrowing it
Nothing to install: this file belongs to Checkmarx/cx-agentic-ai. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/Checkmarx/cx-agentic-ai/master/GEMINI.mdgit clone --depth 1 https://github.com/Checkmarx/cx-agentic-aiWrote 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/instructions/checkmarx/cx-agentic-ai/gemini-md)<a href="https://agentmods.dev/instructions/checkmarx/cx-agentic-ai/gemini-md"><img src="https://agentmods.dev/badge/instructions/checkmarx/cx-agentic-ai/gemini-md/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/instructions/checkmarx/cx-agentic-ai/gemini-md"><img src="https://agentmods.dev/badge/instructions/checkmarx/cx-agentic-ai/gemini-md.svg" alt="Reviewed on agentmods" width="80" 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 5.1 | $0.01546 | $0.01546 |
| Opus 5.5 | $0.00618 | $0.00618 |
| Sonnet 5 | $0.00309 | $0.00309 |
| Haiku 4.5 | $0.00155 | $0.00155 |
Grade A, and why
cx-agentic-ai GEMINI.md 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 today.
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 — 102 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Checkmarx cx-devassist (Gemini CLI)
This extension provides automatic security hooks and on-demand skills. They serve different purposes — do not conflate them.
Automatic hooks (always on)
BeforeTool hooks run on scannable file writes (WriteFile, write_file, write_.*, replace)
and Checkmarx MCP calls (mcp_.*) without skill activation:
- Gate (
cx_check) — provescxis installed, capable, and authenticated before a scannable write or MCP call proceeds. - Scanner (
cx hooks gemini-before-file-tool/gemini-before-tool) — scans proposed file content (ASCA/SAST, KICS/IaC, SCA/manifests) or enforces MCP policy.
Shell commands (run_shell_command) are not gated. A single non-blocking observer records OAuth
URL/tenant pairs from cx auth login so a later session can offer them — it never blocks.
An AfterAgent lifecycle hook (cx hooks gemini-after-agent) runs at the end of each agent turn for
advisory cleanup/telemetry — the Gemini equivalent of Claude Code's Stop → claude-stop. It is
non-blocking and does not gate writes or MCP calls.
Writes to file types Checkmarx cannot scan (.md, .css, .sql, .sh, plain .txt, etc.)
proceed without the readiness gate. See config/cx-scannable-files and
docs/gemini-cli-devassist.md for the full list.
When the user asks you to create, edit, scaffold, or add dependencies as part of normal development — and is not explicitly asking for a security scan or audit:
- Do not proactively activate
cx-devassist-asca,cx-devassist-sca, orcx-devassist-kics. Use the file-write tool directly instead. - Scannable files (
package.json,requirements.txt,app.py,main.tf, … — seeconfig/cx-scannable-files) are checked by the automatic hook chain: readiness gate first, then native scan of the proposed content. The write is denied ifcxis not ready or a real finding is detected. - Unscannable files (
.md,.css,.sql,.sh, plain.txt, …) are not gated — proceed with the write normally. - If a hook denies because
cxis missing, outdated, or unauthenticated, activatecx-cli-setup, fix readiness, then retry the same write — do not skip setup and do not activate ASCA/SCA skills instead. - If a hook denies because of a security finding, follow the triage flow below (remediate vs suppress) — do not retry the write until the developer decides.
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.
- today Changed · +3 lines · +73 tokens per session ae38ae098153
- 8d ago First seen · 99 lines · 1,473 tokens per session scan A 39bc9b53751d
cx-agentic-ai GEMINI.md is an instructions file published in the GitHub repository Checkmarx/cx-agentic-ai (0 stars, last pushed yesterday), licensed Apache-2.0. It adds 1,546 tokens to every session, about $0.0062 per session on Opus 5.5. 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 2026-09-16.
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