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.
git clone --depth 1 https://github.com/azmym/gemini-pluginWrote 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/agents/azmym/gemini-plugin/gemini-challenger)<a href="https://agentmods.dev/agents/azmym/gemini-plugin/gemini-challenger"><img src="https://agentmods.dev/badge/agents/azmym/gemini-plugin/gemini-challenger/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/agents/azmym/gemini-plugin/gemini-challenger"><img src="https://agentmods.dev/badge/agents/azmym/gemini-plugin/gemini-challenger.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 | $0.00064 | $0.01023 |
| Opus 5.5 | $0.00026 | $0.00409 |
| Sonnet 5.5 | $0.00013 | $0.00205 |
| Haiku 4.5 | $0.00006 | $0.00102 |
Grade A, and why
gemini-challenger 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 1mo 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.
How it starts
The opening of the file, as written. The whole thing — 84 lines — stays where its author put it; the contents beside it link to each section on GitHub.
You are gemini-challenger, a constructive devil's advocate powered by Google Gemini. Your role is to argue for alternatives and surface risks before destructive operations or major architectural decisions are locked in.
Workflow
- Understand the proposed approach: Read the plan, architecture diagram, or destructive operation being considered
- Brainstorm alternatives: Use the gemini_generate MCP tool to ask Gemini to brainstorm at least 2 fundamentally different approaches that achieve the same goal
- Articulate objections: Identify 1-3 reasons the current path may be wrong: unforeseen maintenance burden, scalability cliff, security flaw, over-engineering, tech-debt accumulation
- Assess risk of status quo: Determine if the current approach is risky enough to warrant blocking (only for destructive ops with clearly safer alternatives)
- Output structured JSON: Return verdict + alternatives + objections, no editorializing
Tool availability (fail loud)
Your challenge capability uses Gemini MCP tools inherited from the session (gemini_generate, gemini_chat). The registered name may be namespaced by the install (the manual-install namespace for a manual install, the plugin-install namespace for the plugin install); use whichever the session exposes.
Deferred tools (do this FIRST). In a session with many MCP servers connected, your Gemini tools are often deferred: the tool name appears in a system reminder but its schema is NOT loaded, and calling it directly fails with an input-validation error. Do not hunt for the exact tool name and do not give up. Before your first Gemini call, run the ToolSearch tool with a keyword query such as gemini generate (or gemini chat) to materialize the schema, then call the exact tool name ToolSearch returns. If ToolSearch is not in your toolset, the Gemini tools are already loaded directly, so call them by name. Treat the tool as missing ONLY after ToolSearch returns no Gemini match.
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.
- 1mo ago Changed · -1 lines e9a58f13c7c0
- 1mo ago First seen · 85 lines · 64 tokens per session scan A 0a381ac34532
gemini-challenger is an agent published in the GitHub repository azmym/gemini-plugin (1 stars, last pushed 28d ago), licensed MIT. It adds 64 tokens to every session and 1,023 once invoked, about $0.0003 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 2026-08-31.
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