# GPT-5.6 Terra — API pricing & integration guide | Y-API

> GPT-5.6 Terra is the middle tier of the 5.6 generation, listed between the Sol and Luna entries with a 1,050,000-token window and file, image and text input. The reference positions it for everyday coding and agentic tasks.

This is the markdown representation of https://y-api.bestvirtualgoods.com/models/openai/gpt-5.6-terra. Generated by `scripts/generate-seo-assets.mjs` from the same copy the page renders — do not edit by hand.

Model ID: `openai/gpt-5.6-terra`

Sources reviewed: 2026-10-21. Y-API catalog snapshot: 2026-10-21.

## Choosing this model

Selection advice by Y-API. The checks below are suggested evaluations, not published test results.

### Where to start

Use it as the default for routine engineering work — implementing a scoped ticket, writing tests around existing behaviour, reviewing a pull request — where Sol is more than the task needs.

### What to watch for

The tier structure is the publisher’s framing. Terra sitting between two other entries tells you about positioning, not about which model will pass your acceptance checks; measure that yourself.

## Model specifications

These are OpenRouter model-level specifications, not a Y-API compatibility test. A particular route may accept fewer input formats, parameters or tokens. Verify the features you need with a small request; a successful text response does not validate vision or tool calling.

| Field | Value |
| --- | --- |
| Context window | 1,050,000 tokens |
| Input | File, Image, Text |
| Output | Text |
| Listed on OpenRouter | 2026-07-09 |
| Parameters listed by OpenRouter | `include_reasoning`, `max_completion_tokens`, `max_tokens`, `reasoning`, `reasoning_effort`, `response_format`, `seed`, `structured_outputs`, `tool_choice`, `tools`, `verbosity` |

## API pricing & cost estimate

| Price basis | Input / 1M tokens | Output / 1M tokens |
| --- | --- | --- |
| Account credit | $2.00 | $12.00 |
| Cash equivalent | $0.20 | $1.20 |

$1 paid adds $10 of credit. Cash equivalent = credit consumed ÷ 10; this is not the model publisher’s list price.

Input tokens / request: 1000. Output tokens / request: 500. Number of requests: 1000.

Estimated credit consumed: $8.00. Estimated cash equivalent: $0.80.

Illustrative token budget, not measured usage or a quote. Includes input and output; excludes separate media charges, cache discounts and retries. Include billed reasoning tokens in your output budget where applicable. Actual billing follows usage returned by the service.

### Same token budget, different models

| Model | Estimated credit consumed | Estimated cash equivalent |
| --- | --- | --- |
| [GPT-5.6 Terra](https://y-api.bestvirtualgoods.com/models/openai/gpt-5.6-terra) | $8.00 | $0.80 |
| [GPT-5.6 Sol](https://y-api.bestvirtualgoods.com/models/openai/gpt-5.6-sol) | $20.00 | $2.00 |
| [GPT-5.6 Luna](https://y-api.bestvirtualgoods.com/models/openai/gpt-5.6-luna) | $0.95 | $0.095 |

[View LLM API pricing & billing](https://y-api.bestvirtualgoods.com/pricing)

## API integration examples

These minimal, text-only requests use the exact Y-API model ID. They do not demonstrate image, audio, video, file or tool support. The output limit also needs room for reasoning; an empty answer with finish_reason=length can mean the budget was exhausted.

Set the TOKEN environment variable to a key from your console. Run this on your server or locally; never expose a key in browser code or a public repository.

### A task to try

Implement this ticket against the existing interfaces. List the assumptions you made where the ticket was silent, and add a test for each one.

```bash
curl --fail-with-body --silent --show-error --max-time 120 \
  'https://api.y-api.bestvirtualgoods.com/v1/chat/completions' \
  -H "Authorization: Bearer ${TOKEN:?Set TOKEN first}" \
  -H 'Content-Type: application/json' \
  --data-binary @- <<'JSON'
{
  "model": "openai/gpt-5.6-terra",
  "messages": [
    {
      "role": "user",
      "content": "Implement this ticket against the existing interfaces. List the assumptions you made where the ticket was silent, and add a test for each one."
    }
  ],
  "max_tokens": 4096
}
JSON
```

```python
import json
import os
import sys
import urllib.error
import urllib.request

payload = {
  "model": "openai/gpt-5.6-terra",
  "messages": [
    {
      "role": "user",
      "content": "Implement this ticket against the existing interfaces. List the assumptions you made where the ticket was silent, and add a test for each one."
    }
  ],
  "max_tokens": 4096
}

request = urllib.request.Request(
    "https://api.y-api.bestvirtualgoods.com/v1/chat/completions",
    data=json.dumps(payload).encode("utf-8"),
    headers={
        "Authorization": "Bearer " + os.environ["TOKEN"],
        "Content-Type": "application/json",
    },
    method="POST",
)
try:
    with urllib.request.urlopen(request, timeout=120) as response:
        result = json.load(response)
    print(json.dumps(result, ensure_ascii=False, indent=2))
except urllib.error.HTTPError as error:
    print(error.read().decode("utf-8"), file=sys.stderr)
    raise SystemExit(1)
```

### How to evaluate the result

The stated assumptions should match the ones you would have flagged. A run that silently picks a behaviour for an unspecified edge case, with no test, has hidden a decision from you.

## Before you choose

### Terra or Sol for a long agent run?

Start with Terra and record where it fails. Escalating the whole run to Sol because of a few hard steps usually costs more than routing only those steps to it.

## Sources & scope

Technical facts come from the cited model page and, where available, its linked publisher card. A card describes that checkpoint; it is not proof of the weights a gateway serves. Prices come only from the Y-API catalog. We do not claim measured latency, uptime or benchmark scores for this endpoint.

- [OpenRouter model page & specifications](https://openrouter.ai/openai/gpt-5.6-terra)
- [Y-API catalog & prices (JSON)](https://y-api.bestvirtualgoods.com/models.json)

## Models to compare

Compare these alternatives on the same inputs. Their descriptions explain different roles; a lower price does not establish equivalent quality.

### [GPT-5.6 Sol](https://y-api.bestvirtualgoods.com/models/openai/gpt-5.6-sol)

GPT-5.6 Sol is the flagship entry of the GPT-5.6 family in OpenRouter’s catalog. Its stated focus is complex reasoning, command-line coding and multi-step problem solving, with text, image and file inputs listed in the reference.

### [GPT-5.6 Luna](https://y-api.bestvirtualgoods.com/models/openai/gpt-5.6-luna)

GPT-5.6 Luna is the GPT-5.6 entry aimed at high-volume, latency-sensitive chat, classification and lightweight agent tasks. It is a separate cost-efficiency candidate, not a claim of Sol-equivalent reasoning at a lower price.

## Links

- HTML version of this page: https://y-api.bestvirtualgoods.com/models/openai/gpt-5.6-terra
- Site index for agents: https://y-api.bestvirtualgoods.com/llms.txt
- Full reference (single file): https://y-api.bestvirtualgoods.com/llms-full.txt
- OpenAPI 3.1 spec: https://y-api.bestvirtualgoods.com/openapi.json
- Model catalog (JSON, no key needed): https://y-api.bestvirtualgoods.com/models.json
- API base URL: `https://api.y-api.bestvirtualgoods.com/v1`
- Contact: support@bestvirtualgoods.com
- Model catalog: https://y-api.bestvirtualgoods.com/models
- Integration guide: https://y-api.bestvirtualgoods.com/docs