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Gemini 4 Argon

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Native Gemini requests, multimodal inputs, thinking, tools, streaming and continuation. Includes current verification limits.

Use gemini-4-argon with the native Gemini format. The model page includes the Playground and current prices; the release guide explains availability.

Model ID

Model IDContext windowDefault effort
gemini-4-argon1,048,576 tokensmedium

Quick example

curl https://api.seedrouter.ai/v1beta/models/gemini-4-argon:generateContent \
  -H "Authorization: Bearer $SEEDROUTER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"contents":[{"role":"user","parts":[{"text":"Explain a mutex in one sentence."}]}],"generationConfig":{"thinkingConfig":{"thinkingLevel":"low"},"maxOutputTokens":256}}'

The model belongs in the URL. contents is required. An answer includes native candidates, finishReason and usageMetadata; retain complete content parts, including thoughtSignature, for conversation history.

Endpoints

OperationEndpoint
JSON responsePOST /v1beta/models/gemini-4-argon:generateContent
Server-sent eventsPOST /v1beta/models/gemini-4-argon:streamGenerateContent?alt=sse

The OpenAPI specification includes every nested request and response schema. Optional fields use API defaults when omitted. Unknown and officially unsupported fields are discarded; invalid values of supported fields remain errors.

Parameters

NameTypeRequiredDefaultNotes
contentsobject[]Yes—Required conversation array; parts carries text, media and tool results
systemInstructionobjectNo—Text-only system instruction
generationConfigobjectNo—Output budget, thinking, structured output, stopping and media settings
toolsobject[]No—Functions and built-in tool definitions
toolConfigobjectNo—Function selection, retrieval settings and server tool parts
safetySettingsobject[]No—Unique category and threshold pairs
continuationTokenstringNo—Opaque continuation token from the latest candidate
serviceTierenumNostandardunspecified, standard, flex, priority; standard by default
labelsobjectNo—Lowercase label keys and values, up to 63 Unicode characters each
storebooleanNo—Request logging preference; does not provide stored conversation retrieval
modelstringNo—Optional body resource name; the URL fixes the model

generationConfig includes maxOutputTokens, thinkingConfig, stopSequences, responseFormat, legacy responseMimeType/responseSchema/responseJsonSchema, responseModalities, mediaResolution, seed, presencePenalty, frequencyPenalty, responseLogprobs, logprobs, enableEnhancedCivicAnswers, enableAffectiveDialog, translationConfig and audioTranscriptionConfig. Generic fields without confirmed model-specific behavior remain subject to capability verification.

  • Thinking levels: low, medium, high; default medium. Thinking cannot be disabled. includeThoughts requests summaries. Deprecated thinkingBudget is accepted alone, but cannot be combined with thinkingLevel.
  • Input, thinking and output share 1,048,576 tokens. maxOutputTokens includes thinking; the remaining context may reduce the effective budget.
  • Native REST uses a per-request output ceiling/default of 32,768 tokens, or 65,536 when streaming. Longer output uses continuation. Official documentation conflicts on first non-streaming requests above 32,768; this integration does not impose that as a total-generation limit.
  • At most five stopSequences. logprobs ranges from 0 to 20 and requires responseLogprobs: true.
  • responseSchema and responseJsonSchema are mutually exclusive and require responseMimeType: "application/json". New requests can use responseFormat.text below.
  • responseModalities can contain TEXT only. Temperature, top-p, top-k and candidate count are not active Argon controls. Explicit cachedContent, image generation and speech generation are unsupported.

Structured output and tools

{
  "contents": [{"parts": [{"text": "Return a JSON object with ok set to true."}]}],
  "generationConfig": {
    "thinkingConfig": {"thinkingLevel": "low"},
    "maxOutputTokens": 256,
    "responseFormat": {
      "text": {
        "mimeType": "APPLICATION_JSON",
        "schema": {"type": "object", "properties": {"ok": {"type": "boolean"}}, "required": ["ok"]}
      }
    }
  }
}

Functions use tools[].functionDeclarations. allowedFunctionNames requires mode ANY or VALIDATED and declared names. Keep function calls, responses and signatures in their original order. Google Search, Maps, code execution, URL context, File Search and Computer Use are official capabilities; resource access, charges and behavior must be verified for your intended operation. Tools are not executed locally by the Playground.

Media and safety

Native parts accepts text, image, audio, video and PDF inputs through inlineData or fileData. A part contains one payload variant, optionally accompanied by thought signatures and media metadata. Global mediaResolution and per-part resolution are distinct. Video supports STATIC and AGENTIC processing; videoMetadata.fps is greater than zero and at most 24.

The Playground accepts a JSON request up to 12 MiB. This is an application transport limit, not the model’s media limit. For large media, use file references supported by your account. File resources and externally fetched media have different official limits; their availability has not yet been verified here.

Public API safety settings follow the native contract. The Playground requires medium-or-higher blocking for the four principal safety categories; lower thresholds are API only, with an administrator exception.

Streaming and continuation

Read native JSON events from the SSE stream. Keep all parts, including tool and thinking metadata. Usage counters within one stream are cumulative: use the last usage object rather than adding every event.

When a candidate returns continuationToken, preserve it exactly. For CONTINUATION, resend the original contents, system instruction, tools and generation settings with the latest token at the top level. Do not append partial output to contents. For MAX_TOKENS, increase the output budget before resuming. The Playground prepares a continuation request for review and sends it only when you press Send again.

Each continuation is a separate request with its own usage and charge. Keep checkpoints if you implement reconnects; never assume a disconnected stream completed. The native response is retained in the Playground for inspecting all fields.

Usage and current verification status

Input usage includes cached input; billable output includes candidate and thinking tokens. Consult the current model-page rates and your account usage records. Failed requests are not charged.

Local checks on October 14, 2026 verified text streaming, structured JSON, signed function-call round trips, code execution, Google Search and URL context, image/video/PDF understanding, thinking output and stop sequences. Audio was accepted but part of the sample was transcribed incorrectly.

logprobs was explicitly rejected. Requests with maxOutputTokens: 32769 failed in both JSON and SSE checks. A valid and an invalid continuationToken both returned answers, so correct continuation is not verified. Service-tier choices and seed were accepted without proof of their effect. Maps, File Search, Computer Use, agentic video and external file references remain untested.

These limited checks do not establish every parameter combination or production availability. Use the native format for the complete contract; OpenAI compatibility is a separate subset and does not provide long decode.

References

Optional LLM group

Sign in to this model's Playground to check the available groups. Options depend on your account permissions and the selected model. Playground uses your login session; you do not need to provide an API key.

API calls keep your API key and model ID. To select a group, send its exact name in the optional X-SeedRouter-Group request header. Replace GROUP_NAME below with a name shown in Playground. Omit the header or use auto to keep the key's default behavior.

X-SeedRouter-Group: GROUP_NAME

A restricted API key may have fewer group options than Playground. Requests use the selected group's pricing and do not switch to another group if it is unavailable. This option supports HTTP LLM calls, including SSE; it does not apply to WebSocket, image or video calls.

To check the groups available to a particular API key without generating a response, use this read-only endpoint. data[].id is the header value; ratio is the account's price multiplier for that group. The auto entry reflects the current default estimate; its ratio is null when no default group is available. Group availability is checked again when you call the model.

curl "https://api.seedrouter.ai/api/seedrouter/llm/groups?model=gemini-4-argon" \
  -H "Authorization: Bearer YOUR_SEEDROUTER_KEY"