GPT-5.6 Sol API: Endpoint & 25% Discount
Up to 25%GPT-5.6 Sol is available on LLM.API as an OpenAI-compatible chat endpoint—route Gpt Sol quality through one key with transparent token pricing.
What is GPT-5.6 Sol?
GPT-5.6 Sol is a Gpt Sol chat model exposed on LLM.API under id `gpt-5.6-sol`. Frontier GPT-5.6 model for complex professional work, coding, and agentic workflows. Teams use it when they need reliable text generation with text, image inputs and text outputs over an OpenAI-compatible API.
Can you self-host GPT-5.6 Sol?
No. We found no public weights for GPT-5.6 Sol on Hugging Face, so there is nothing to download, quantize or serve on your own GPUs: no VRAM budget, no vLLM or GGUF build to plan for. The only way to run it is over an API.
Skip the deploy — use LLM.API as your endpoint
No GPUs, no quantization trade-offs. Same model, OpenAI-compatible, up to 25% below list price.
Providers
LLM.API routes GPT-5.6 Sol to the providers below, with discounted effective rates versus list price.
List price by provider
InputOutputProvider list prices; the LLM.API discount applies on top.
| Provider | Pricing | Context | Capabilities |
|---|---|---|---|
| in $4; out $20 per 1M tokens | 1.1M tokens | vision, tools, streaming, reasoning, web search, JSON, structured | |
| in $4; out $20 per 1M tokens | 1.1M tokens | vision, tools, streaming, reasoning, web search, JSON, structured | |
| in $4; out $20 per 1M tokens | 1.1M tokens | vision, tools, streaming, reasoning, web search, JSON, structured |
Prices and availability from the LLMAPI catalogue, updated nightly. Last updated 11 Oct 2026.
Try this model
Test GPT-5.6 Sol right here — free to start.
Suggestions for your first prompt
Code snippet
Call GPT-5.6 Sol through the OpenAI-compatible API — POST /v1/chat/completions.
Switching from OpenAI? Change 2 lines.
- base_url="https://api.openai.com/v1"
- api_key="YOUR_OPENAI_KEY"
+ base_url="https://api.llmapi.ai/v1"
+ api_key="YOUR_LLMAPI_KEY"Everything else stays the same — SDK, message format, tools, streaming. Set model to gpt-5.6-sol and the call runs unchanged.
curl https://api.llmapi.ai/v1/chat/completions \
-H "Authorization: Bearer $LLMAPI_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "gpt-5.6-sol",
"messages": [
{"role": "user", "content": "Give me three crisp launch checklist items."}
],
"reasoning_effort": "medium"
}'from openai import OpenAI
client = OpenAI(
api_key="YOUR_LLMAPI_KEY",
base_url="https://api.llmapi.ai/v1",
)
resp = client.chat.completions.create(
model="gpt-5.6-sol",
messages=[
{"role": "system", "content": "You are a precise product assistant."},
{"role": "user", "content": "Give me three crisp launch checklist items."},
],
reasoning_effort="medium",
)
print(resp.choices[0].message.content)import OpenAI from "openai";
const client = new OpenAI({
apiKey: process.env.LLMAPI_KEY,
baseURL: "https://api.llmapi.ai/v1",
});
const resp = await client.chat.completions.create({
model: "gpt-5.6-sol",
messages: [
{ role: "user", content: "Give me three crisp launch checklist items." },
],
});
console.log(resp.choices[0].message.content);stream = client.chat.completions.create(
model="gpt-5.6-sol",
messages=[{"role": "user", "content": "Write a haiku about latency."}],
stream=True,
)
for chunk in stream:
delta = chunk.choices[0].delta.content
if delta:
print(delta, end="", flush=True){
"model": "gpt-5.6-sol",
"messages": [
{"role": "system", "content": "You are a precise product assistant."},
{"role": "user", "content": "Give me three crisp launch checklist items."}
],
"reasoning_effort": "medium"
}ENDPOINTS
Supported endpoints & features
Base URL https://api.llmapi.ai/v1 · model ID gpt-5.6-sol · OpenAI-compatible.
POST /v1/chat/completionsChat Completions — supported
| Feature | Status | How to set it |
|---|---|---|
| Function calling (tools) | Supported | tools, tool_choice |
| Parallel tool calls | Not supported | parallel_tool_calls |
| JSON mode | Supported | response_format: {"type": "json_object"} |
| Structured outputs | Supported | response_format: {"type": "json_schema", …} |
| Streaming | Supported | stream: true |
| Vision (image input) | Supported | image_url content parts |
| Web search | Supported | web_search |
| Reasoning effort | none · low · medium · high · xhigh · max | reasoning_effort: "medium" default medium |
ERRORS
Errors & fallback routing
| Code | What it means | What to do |
|---|---|---|
401 | Missing or invalid API key. | Send Authorization: Bearer YOUR_LLMAPI_KEY and check the key is active. |
429 | Rate limited, or the upstream provider is throttling the request. | Back off and retry with jitter; the gateway also retries the request on another provider where one is available. |
5xx | Upstream provider error or timeout. | Retry; fallback routing sends the retry to the next healthy provider for this model. |
When a provider fails or throttles, the request is routed to the next provider serving this model — the ones listed in the providers table above.
GPT-5.6 Sol in production
What the model is good at.
Tool-ready dialogue
Works well in agent loops that call functions, browsers, or retrieval APIs. Reflects Gpt Sol positioning for this endpoint.
Analytical writing
Produces clear analyses, comparisons, and decision memos from messy source material. Relevant for `gpt-5.6-sol` workloads on LLM.API.
Instruction following
Follows detailed system and user instructions with strong adherence to format and tone. Tuned to how teams typically call GPT-5.6 Sol.
Conversational UX
Maintains coherent multi-turn assistant behavior for product chat surfaces. Relevant for `gpt-5.6-sol` workloads on LLM.API.
Multi-step reasoning
Breaks down complex problems into intermediate steps before answering. Grounded in the model's chat role rather than generic chat claims.
What you get when you call GPT-5.6 Sol through LLM.API.
Unified AI Routing
Production: Reach GPT-5.6 Sol and sibling models through one OpenAI-compatible endpoint.
One endpoint, every model.Cost Control
Practical: Compare provider price points and keep spend visible as you scale GPT-5.6 Sol.
More performance, less spend.Reliability Layer
Practical: Retry and route across configured providers when a single upstream blips.
Never go dark on users.Observability
Production: Trace prompts, tokens, and errors for GPT-5.6 Sol alongside the rest of your stack.
See every token, everywhere.Drop-in SDKs
Production: Keep using familiar OpenAI client patterns with base URL https://api.llmapi.ai/v1.
Think tasks, not models.Model Breadth
Practical: Swap GPT-5.6 Sol for chat, media, or embedding alternatives without rewriting auth.
Scale from 1 to millions.
When to Use — When NOT to Use
Use it if...
- Your prompts benefit from the model's family strengths (reasoning, speed, or cost) (GPT-5.6 Sol)
- You need a general-purpose text model for assistants, agents, or content workflows (GPT-5.6 Sol)
- You want OpenAI-compatible chat completions through a single LLM.API key (GPT-5.6 Sol)
- You need provider failover options exposed for this model id (GPT-5.6 Sol)
Avoid if...
- You require on-prem only deployment with no cloud inference
- Your use case depends on unpublished proprietary benchmarks not listed here
- You need pure embedding, OCR, or media generation instead of chat
- You need guaranteed real-time hard latency SLAs without benchmarking the provider
BENCHMARKS
GPT-5.6 Sol benchmark scores
Intelligence index
Scale: 0-100 index points
Output speed
Scale: 0-400 tokens per second
Reference price per 1M tokens
Bars compare input and output list prices for this model.
Higher is better. The median covers every model tracked by Artificial Analysis.
Measured throughput; the full dial is 300 tokens per second.
Provider list prices, before the LLM.API discount.
Independent scores published by Artificial Analysis (source). Reference prices are provider list prices, not LLM.API pricing.
COMMUNITY
What developers say about OpenAI models
Summarised from publicly published developer and community reviews of this model family. Opinions are the sources’, not LLM.API’s, and may not be specific to GPT-5.6 Sol.
- Long-horizon coding reports on GPT-6 Astra describe a clear step up over the GPT-5.x line, with the higher reasoning tiers seen as the sweet spot for planning and implementation in large (100K+ LOC) codebases.
- The same field reports note that fast/ultra modes burn quota quickly and that very large refactors still stall, so teams tend to mix a cheap tier for routine calls with a reasoning tier for hard steps.
- Community threads temper the hype: capability gains are acknowledged, but developers still report the usual failure modes on obscure reverse-engineering and modding work.
SOURCES
Frequently Asked Questions
Where is the canonical page for GPT-5.6 Sol?
https://llmapi.ai/models/openai-gpt-5-6-sol/
Does GPT-5.6 Sol support streaming?
Yes—at least one listed provider advertises streaming.
What is GPT-5.6 Sol?
Frontier GPT-5.6 model for complex professional work, coding, and agentic workflows. On LLM.API it is addressed as `gpt-5.6-sol`.
Is GPT-5.6 Sol a chat model?
Yes—GPT-5.6 Sol is exposed as a chat/completions-style endpoint on LLM.API.
Which providers serve GPT-5.6 Sol?
LLM.API currently lists: azure, openai. Availability can vary by region and account.
What modalities does GPT-5.6 Sol support?
GPT-5.6 Sol accepts text, image and produces text according to its architecture metadata on LLM.API.
What is the context length for GPT-5.6 Sol?
Reported context for GPT-5.6 Sol is 1.1M tokens. Always verify the active provider row if multiple providers are listed.
What are limitations of GPT-5.6 Sol?
Like other API models, GPT-5.6 Sol can be wrong, incomplete, or uneven on edge cases. Validate outputs for high-stakes use. Media/OCR/STT models additionally depend on input quality.
When should I choose GPT-5.6 Sol?
You need a general-purpose text model for assistants, agents, or content workflows — especially when you specifically need GPT-5.6 Sol.
How is GPT-5.6 Sol priced on LLM.API?
Listed pricing metadata shows: In $5.00 / 1M tokens · Out $30.00 / 1M tokens. LLM.API may offer discounted effective rates (illustrative ~30% callout vs list when available).. Confirm live rates in the LLM.API dashboard or docs before production budgeting.
Can I use tools or structured outputs with GPT-5.6 Sol?
Tool and/or structured-output flags appear on one or more providers for this model—confirm in the providers table.
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