| name | gemini-cli |
| description | Delegates large multi-step work to Gemini CLI like a subagent—include full goal, prior decisions, scope, and constraints in prompts so isolated sessions stay aligned with the main thread (context handoff per Cognition-style delegation). Use for heavy edits, exploration, web search, @codebase_investigator, @generalist, or @gemini-cli-security. Skip for trivial one-shot tasks or when everything is already in context. |
| allowed-tools | ["Bash","Read","Write","Grep","Glob"] |
Gemini CLI (subagent/task delegation)
[!WARNING]
DEPRECATED: Gemini CLI has been deprecated in favor of Antigravity CLI (agy). We strongly recommend migrating to /antigravity-cli for up-to-date features (sandbox confinement, /agents dashboard, dynamic status lines, and first-class subagent orchestration). Legacy support for gemini remains available.
Use Gemini CLI to run a separate long-horizon pass over the repo: multi-step implementation, broad refactors, batch file writes, or deep exploration—similar to handing a task to a subagent. You stay orchestrator: smaller prompts, less context burn, often lower spend than doing the same work entirely in-session.
Inside Gemini CLI, subagents are specialists. Prefer @name prefix in the Gemini prompt to force one (e.g. @codebase_investigator Map auth flow). Core specialists include codebase_investigator, generalist, and gemini-cli-security.
When to use Gemini CLI
- Large or multi-step work: several files, phases, or checkpoints (feature slice, migration, test suite, docs sweep).
- Heavy code generation or editing: Gemini drives
--yolo tool use while you summarize outcomes and merge.
- Parallel mental lane: you continue planning or reviewing while Gemini runs a bounded task (optionally background—see reference.md).
- Built-in specialists:
@codebase_investigator for architecture / dependency mapping; @generalist for heavy multi-file subtasks with isolated context; @gemini-cli-security for security-focused passes.
- Powerful Web Search: Delegate deep research or API documentation searches to Gemini to leverage its integrated Google Search grounding. Use this when the main agent needs up-to-date information not present in the local context.
- Fresh tool stack: Google Search grounding, MCP tools, and other Gemini-only capabilities.
- User explicitly asks for Gemini or “use Gemini for this.”
When not to use
- Small / single-step tasks answerable with one or two edits or a short explanation.
- Tight feedback loops where the user wants rapid back-and-forth refinement in one thread.
- Secrets or policy-sensitive flows—avoid piping credentials; redact before delegating.
- Already-loaded context where duplicating the whole plan adds no value—handle locally.
- Low ROI (Return on Investment): If the task is "needle-in-a-haystack" (requires high precision over a single line) or if the time to compose the Handoff Table exceeds the time to simply edit the file locally. Delegation should only be used when the "mental offloading" outweighs the "handoff overhead."
Delegation and context (critical)
Isolated subagent context saves tokens but splits the story: Gemini does not see the main session's full thread. Poor handoffs cause misread subtasks, conflicting assumptions (stack, style, APIs), and wasted edits—see Cognition’s discussion of sharing context and implicit decisions in multi-step setups.
When composing the single Gemini prompt, treat it as passing enough shared state, not just a title:
| Include | Why |
|---|
| Original goal | Same north star as the user—not only the immediate micro-task. |
| Decisions already made | Framework, patterns, naming, auth approach, “use X not Y”—anything that would otherwise be guessed wrong. |
| Scope | Paths, modules, env (@paths), and explicit out of scope / do-not-touch areas. |
| Constraints | Performance, a11y, compatibility, review gates, “no new deps,” etc. |
| Verification | Explicit command (e.g. npm test, lint) the subagent must run and pass before returning. |
| Expected output | e.g. “summarize then list files changed,” “report only—no edits,” or “apply edits with minimal diff.” |
After Gemini returns, pull decisions and constraints back into the main thread (what it assumed, what it changed, open risks). Prefer sequential delegations with explicit carry-over over parallel runs that might diverge unless they share the same briefing.
If the delegation would need a long transcript to be safe, summarize the relevant parts into the prompt (compressed “state of the union”) rather than a one-line subtask.
Model Selection & Discovery (Mandatory)
MANDATORY: Search the web for latest Gemini model names/aliases and pricing before selecting a model. You should also consult Artificial Analysis for the most up-to-date benchmarks, pricing, and model performance data. Names change monthly; using stale names causes failures.
- Default (Simple Tasks):
gemini-3.5-flash (Use for speed, research, and formatting).
- Heavy Tasks:
pro (Alias for latest gemini-3.1-pro-preview or gemini-3.1-pro). Use for deep reasoning and large-scale refactors.
- Strategy: Always default to
gemini-3.5-flash to minimize costs. Only escalate to pro for critical architecture tasks after verifying latest version and cost via search.
Programmatic usage (required)
You MUST use Gemini CLI programmatically. Do NOT start interactive sessions.
| Requirement | Flag |
|---|
| Auto-approval | --yolo or -y |
| Silent output | -o text (for clean response) |
| Model Selection | -m [model_name/alias] |
| JSON stats | -o json (if statistics are needed) |
Command pattern
gemini "[prompt with @paths as needed]" --yolo -o text -m gemini-3.5-flash 2>&1
After Gemini returns
- Review diffs and security-sensitive areas (XSS, injection, auth)—do not merge blindly.
- Run project checks (
lint, test, typecheck) as appropriate.
- Compress results for the user: summarize results for the user instead of pasting huge logs unless asked.
- Reconcile context: note decisions, files touched, and remaining risks so the main session stays aligned.
Quick prompts
- Delegate implementation:
gemini "GOAL: [goal] | DECISIONS: [decisions] | SCOPE: [paths] | CONSTRAINTS: [constraints] | VERIFICATION: [test_command] | OUTPUT: [format]" --yolo -o text -m gemini-3.5-flash
- Investigate:
gemini "@codebase_investigator GOAL: Map how [feature] works | SCOPE: [paths] | OUTPUT: concise file:line map" --yolo -o text
- Web Search:
gemini "GOAL: Find latest documentation for [library] | CONSTRAINTS: focus on breaking changes in [version] | OUTPUT: summary report" --yolo -o text
- Security:
gemini "@gemini-cli-security GOAL: Audit for injection/XSS/auth issues | SCOPE: @./src | OUTPUT: report with severities" --yolo -o text
More detail
- Delegation checklist (short): reference.md
- Flags, JSON output, sessions, subagents, Auto Memory, worktrees, model steering: reference.md