HERMES + GEMINI

Use Gemini in Hermes Agent.

Google Gemini is available through RunAPI's OpenAI-compatible endpoint. Hermes Agent calls it using the custom:runapi provider — Gemini 3.5 Flash for speed-sensitive agent loops, 3.x Pro for multi-step reasoning, 2.5 Pro for long-context production tasks. No Google Cloud project or Vertex AI credentials required — just the same RUNAPI_API_KEY and base_url you already configured for chat.

Get API Key Read the docs
one API key · OpenAI-compatible chat endpoint · streaming support 
Use RunAPI to send a chat request to Google Gemini 3.5 Flash through Hermes Agent.

Requirements:
- Use the custom:runapi provider already configured in Hermes Agent
- Call the RunAPI chat completions endpoint at https://runapi.ai/v1/chat/completions
- Set model to "gemini-3.5-flash"
- The RUNAPI_API_KEY environment variable provides authorization
- The response is synchronous — the reply arrives in choices[0].message.content
- For streaming, set stream to true and process server-sent events

curl -X POST https://runapi.ai/v1/chat/completions \
  -H "Authorization: Bearer $RUNAPI_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gemini-3.5-flash",
    "messages": [
      {"role": "system", "content": "You are a concise technical assistant."},
      {"role": "user", "content": "Explain the difference between gRPC and REST in three sentences."}
    ],
    "temperature": 0.7,
    "max_tokens": 256
  }'

{
  "id": "chatcmpl-abc123",
  "object": "chat.completion",
  "model": "gemini-3.5-flash",
  "choices": [
    {
      "index": 0,
      "message": {
        "role": "assistant",
        "content": "gRPC uses HTTP/2 and Protocol Buffers for strongly-typed, multiplexed RPC calls with built-in code generation. REST uses HTTP/1.1 (or 2) with JSON payloads and relies on URL paths and HTTP verbs for resource semantics. gRPC is faster for service-to-service calls; REST is simpler to debug and more widely supported by browsers."
      },
      "finish_reason": "stop"
    }
  ],
  "usage": {
    "prompt_tokens": 34,
    "completion_tokens": 71,
    "total_tokens": 105
  }
}
Copy the curl command to test gemini
HOW IT WORKS

Use Gemini in Hermes Agent in three steps

1

Configure RunAPI

Set the RUNAPI_API_KEY environment variable. If you already added RunAPI as a custom:runapi provider in Hermes Agent, the same key and base_url work for Gemini — change only the model ID. No Google Cloud credentials needed.

export RUNAPI_API_KEY=runapi_xxx
2

Call Gemini via chat completions

Send a POST request to /v1/chat/completions with model set to gemini-3.5-flash. Pass a messages array with system and user roles. Hermes Agent sends the same OpenAI-compatible request shape it uses for GPT — RunAPI routes to Gemini based on the model parameter.

POST /v1/chat/completions
3

Read the response

The response arrives synchronously in OpenAI chat completion format. The assistant reply is in choices[0].message.content, with token usage in the usage object. For streaming, set stream to true and Hermes Agent parses the SSE delta events automatically.

choices[0].message.content
PARAMETERS

Gemini chat completions API parameters

Parameter Type Description
model string Required. gemini-3.5-flash, gemini-2.5-flash, gemini-2.5-pro, gemini-3-flash-preview, gemini-3-pro-preview, or gemini-3.1-pro-preview.
messages array Required. Array of message objects with role (system, user, assistant) and content fields.
temperature number Optional. Sampling temperature between 0 and 2. Lower values produce more deterministic output. Default varies by model.
max_tokens integer Optional. Maximum number of tokens to generate in the response.
stream boolean Optional. When true, the response streams as server-sent events. Each event contains a delta with partial content.
top_p number Optional. Nucleus sampling threshold between 0 and 1. Alternative to temperature for controlling output randomness.

What is Gemini on Hermes Agent?

Google Gemini is available through RunAPI's custom:runapi provider without any Google Cloud credentials. Hermes Agent calls it using the same OpenAI-compatible config used for GPT and Claude. Gemini 3.5 Flash is the fastest option for speed-sensitive agent loops, while Gemini 2.5 Pro offers a 1M token context window and thinking mode for complex multi-step reasoning tasks.

Gemini use cases

Real-time voice and video chat with Live API

Use Gemini's multimodal capabilities for real-time applications that process audio and video input alongside text, building interactive agents that can see and hear through Hermes Agent workflows.

Grounding responses with Google Search data

Enable Google Search grounding on Gemini requests to get responses backed by current web data, useful for agents that need up-to-date information beyond their training cutoff.

Cost-efficient agent tool-calling chains

Run Gemini 3.5 Flash for fast, cheap tool-calling loops where the agent needs to make many sequential calls. Sub-100ms first-token latency keeps agent chains responsive without breaking the budget.

FAQ

Gemini + Hermes Agent questions

Hermes Agent general setup

Not configured yet? Start with the RunAPI setup guide for Hermes Agent.

Hermes Agent setup guide →

Gemini model catalog

See all Gemini variants, pricing tiers, and API documentation.

Gemini models →

Try Gemini in Hermes Agent today.

Get a free RunAPI key, set model to gemini-3.5-flash in your custom:runapi provider, and start using Gemini in Hermes Agent.

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