Gemini gemini-3.5-flash API
Same API, same SDK — switch variants by changing one parameter.
# Works with Claude Code, Codex, Gemini CLI, Cursor, and 50+ agents
npx skills add runapi-ai/gemini -gInstall the Gemini skill for me: 1. Clone https://github.com/runapi-ai/gemini 2. Copy the skills/gemini/ directory into your user-level skills directory (e.g. ~/.claude/skills/ for Claude Code, ~/.codex/skills/ for Codex). 3. Verify that SKILL.md is present. 4. Confirm the install path when done.
gemini-3.5-flash targets the sweet spot of quality and cost within the Gemini family.
- Pay-per-call pricing in USD
- Failed generations not charged
- Streaming when supported by the model
- Schema-validated tool calls
Pricing
Technical details
| Model ID | gemini-3.5-flash |
| Provider | |
| Modality | text |
| Task type | synchronous |
| Billing unit | 1K tokens |
| API endpoint | /v1beta/models/gemini-3.5-flash:streamGenerateContent |
| Commercial license | Yes — included via API |
| Status | Operational |
Quickstart — gemini-3.5-flash
curl -X POST https://runapi.ai/v1beta/models/gemini-3.5-flash:streamGenerateContent \
-H "Authorization: Bearer $RUNAPI_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "gemini-3.5-flash",
"contents": [
{
"parts": [
{
"text": "Analyze this codebase and suggest three performance improvements with before/after examples."
}
]
}
]
}'import { GeminiClient } from "@runapi.ai/gemini";
const client = new GeminiClient();
const result = await client.streamGenerateContent.run({
model: "gemini-3.5-flash",
contents: [{"parts":[{"text":"Analyze this codebase and suggest three performance improvements with before/after examples."}]}],
});require "runapi/gemini"
client = RunApi::Gemini::Client.new
result = client.stream_generate_content.run(
model: "gemini-3.5-flash",
contents: [{parts: [{text: "Analyze this codebase and suggest three performance improvements with before/after examples."}]}]
)Use gemini-3.5-flash in four steps
Install
Install the model SDK or agent skill for this model line.
Configure
Set the model field to the full model ID shown on this page.
Call
Send a typed request with your prompt, inputs, and callback settings.
Receive
Read the task response, webhook callback, or cached output URL from RunAPI.
What's different about gemini-3.5-flash
Fast multimodal streaming for high-volume production workloads
Speed/cost optimized; 1M context; older generation baseline
Fast multimodal streaming for high-volume production workloads
Best reasoning in 2.5 gen; 1M context
Fast multimodal streaming for high-volume production workloads
gemini-3-flash-preview
Best for
Customer support
Answer customer questions from a private knowledge base, reducing ticket volume.
Document analysis
Draft contract summaries and flag key clauses for attorney review.
Code generation
Auto-generate unit tests, code reviews, and refactoring suggestions in CI.
Frequently asked questions about gemini-3.5-flash
Is the model ID stable across versions?
RunAPI keeps the model ID stable and handles compatible version refreshes without changing your request shape.
What's the rate limit on this variant?
Per-key rate limits scale with usage tier. See pricing page for current limits.
Can I switch variants later?
Yes — variant is a flag. Switch by changing the model parameter.
Does it stream?
Where streaming is available, RunAPI streams end-to-end.
Where do I report quality issues?
Open an issue on the public GitHub repo or email support.
