Gemini CLI is a terminal-based AI agent that lets developers interact with Google Gemini models and use tools for tasks such as file operations, shell commands, web fetching, and search. Developers use it from the command line, and the catalogue add-ons extend its workflows and integrations.
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 skills add google-gemini/gemini-cli --skill spec_generatorgit clone --depth 1 https://github.com/google-gemini/gemini-cliWrote 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/google-gemini/gemini-cli/spec_generator)<a href="https://agentmods.dev/skills/google-gemini/gemini-cli/spec_generator"><img src="https://agentmods.dev/badge/skills/google-gemini/gemini-cli/spec_generator/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/skills/google-gemini/gemini-cli/spec_generator"><img src="https://agentmods.dev/badge/skills/google-gemini/gemini-cli/spec_generator.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Snyk warn
- NVIDIA SkillSpector pass
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 | $0.00017 | $0.00862 |
| Opus 5.5 | $0.00007 | $0.00345 |
| Sonnet 5.5 | $0.00003 | $0.00172 |
| Haiku 4.5 | $0.00002 | $0.00086 |
Grade A, and why
spec_generator 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 — 99 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Spec Generator Instructions
Extract key technical details from the issue and organize them according to the following strict JSON schema.
Critical Rules:
- Codebase Verification: Rely on file paths and locations found during your codebase exploration. Ensure all files mentioned in
files_to_modifyactually exist in the repository. Do not make up file paths. - Target File Selection: List all source code files in
files_to_modifywhere code changes belong.- Fix config or state issues early at their setup/hook entrypoint rather than refactoring low-level utilities.
- Strictly do NOT list test files or files that were only inspected without requiring code changes.
- Strict JSON Escaping: Ensure the generated output is standard, valid JSON. In JSON string values (such as summary fields or verification steps), do NOT escape single quotes with backslashes. Write them directly as
'(not\\').
[!IMPORTANT] The output MUST strictly adhere to this schema. Deviations (like putting objects inside arrays instead of strings) will break the downstream automated code generation pipeline.
The final workable_spec object must conform strictly to this JSON Schema specification. Every field listed below is strictly required and must be populated:
{
"type": "object",
"properties": {
"issue_id": {
"type": "string",
"description": "The specific GitHub issue identifier in the canonical format: {owner}/{repo}#{number} (e.g., google/gemini-cli#245)."
},
"summary": {
"type": "object",
"description": "A deep technical summary of the issue.",
"properties": {
"problem": {
"type": "string",
"description": "Concise statement of the problem."
},
"root_cause": {
"type": "string",
"description": "Analysis of the underlying cause of the bug."
},
"context": {
"type": "string",
"description": "Any additional technical context or background."
}
}
},
"implementation_plan": {
"type": "object",
"description": "Details required for code implementation of the fix.",
"properties": {
"files_to_modify": {
"type": "array",
"description": "List of source code files requiring changes relative to the repository root (e.g. ['src/cli.ts']). Strictly do NOT include test files (*.test.ts, *.spec.ts) here; test files must go into testing_strategy.test_file.",
"items": {
"type": "string"
}
},
"steps": {
"type": "array",
"description": "Ordered step-by-step instructions to implement the fix. Each step must be a simple, flat string description. Do not nest objects inside this array.",
"items": {
"type": "string"
}
}
}
},
"testing_strategy": {
"type": "object",
"description": "Instructions for validating the fix.",
"properties": {
"test_file": {
"type": "string",
"description": "Path to the relevant test file relative to the repository root (e.g., 'tests/cli.test.ts')."
},
"expected_behavior": {
"type": "string",
"description": "Description of how the system should behave after the fix."
},
"verification_steps": {
"type": "array",
"description": "Specific steps to add or modify in the test file.",
"items": {
"type": "string"
}
},
"framework": {
"type": "string",
"description": "Testing framework used.",
"enum": ["Vitest", "N/A"]
}
}
}
}
}
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 First seen · 99 lines · 17 tokens per session scan A cebff453fc13
spec_generator is a skill published in the GitHub repository google-gemini/gemini-cli (108,582 stars, last pushed today), licensed Apache-2.0. It adds 17 tokens to every session and 862 once invoked, about $0.0001 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 2026-08-30.
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