gemini-agent - SKILL.md Agent Skill

name: gemini-agent description: > Delegate tasks to Gemini CLI as an agent. Use when the user wants to offload token-heavy work to Gemini, get a second opinion from a different model, or run Gemini with a custom system prompt. Triggers include "use Gemini to review X", "ask Gemini to Y", "run Gemini on Z", "delegate to Gemini", "have Gemini check X".

Gemini Agent

Delegates tasks to Gemini CLI in headless mode using gemini_interface.py from this skill's scripts/ folder.

Prerequisite: Gemini CLI must be installed and on PATH (gemini --version should work).

Basic usage

python ~/.claude/skills/gemini-agent/scripts/gemini_interface.py \
  --prompt "<task prompt>" \
  --cwd "$(pwd)"

With a system prompt file

Pass any markdown file as a persona/role for Gemini. YAML frontmatter is stripped automatically.

python ~/.claude/skills/gemini-agent/scripts/gemini_interface.py \
  --prompt "<task prompt>" \
  --system-md /path/to/persona.md \
  --cwd "$(pwd)"

With a context file

If you need Gemini to read a large existing file, attach it via the --context-file argument (which uses Gemini's @file syntax under the hood):

python ~/.claude/skills/gemini-agent/scripts/gemini_interface.py \
  --prompt "Review this file for security vulnerabilities." \
  --context-file src/auth/login.py \
  --cwd "$(pwd)"

Note: For short context or summaries (a few sentences), do not create a temp file. Just include the context directly inside your --prompt string!

Options

Flag	Default	Description
`--prompt`	required	Task prompt
`--system-md`	none	Markdown file prepended as system instructions
`--context-file`	none	File attached via `@path` in the prompt
`--cwd`	current dir	Working directory for Gemini CLI
`--model`	`gemini-3.1-pro-preview`	Gemini model ID
`--verbose`	off	Stream all output; default is final response only

Running in background (parallel with other work)

# Launch as a background task so Claude can continue working in parallel
Bash("python ~/.claude/skills/gemini-agent/scripts/gemini_interface.py --prompt '...' --cwd $(pwd)", run_in_background=true)

Constructing good prompts

Gemini has no conversation context. Include everything it needs:

Which files or components to examine
What specifically to look for
What format to return (e.g., "list issues with file:line references")