If a software team wants a compact picture of GPT-6.1 Terra, the listing centers on five practical axes: what it can accept, what it returns, how far it reasons, how fast it is, and how much it costs. The entry model id is gpt-6.1-terra, and the trial path mentioned is a Playground comparison rather than a long narrative.
| Reasoning tier | Highest |
|---|---|
| Speed profile | Fast |
| Listed price markers | $1 • $5 |
| Accepted input | Text, Image |
| Produced output | Text |
| Model id | gpt-6.1-terra |
The same overview frames the model around visual inference, precise computer interaction, and clear natural-language writing, while positioning it as a fast and efficient option for comparison work.
From a software standpoint, those examples describe an image-aware text assistant rather than a media producer. The listing gives enough detail to test whether screen or document understanding matters more than output type.
For reasoning.effort, the listed values are none, low, medium, high, xhigh, and max, with medium marked as default. The overview also states that the Responses API is required for tool calling. Prompting and migration guidance is pointed to the GPT-6 guide.
Those two notes matter during implementation. If a team only needs conversational text generation, the endpoint question may be simple. If a team plans tool use, the endpoint constraint becomes part of architecture review rather than an afterthought.
The knowledge boundary is especially relevant for software readers who expect model answers to reflect a fixed information horizon. The context and output ceilings can be read together when estimating whether a workflow can hold large documents or produce long generated text without external chunking.
Costs depend on token counts or other metrics tied to the model type. Tool-specific models such as search and computer use also incur a fee per tool call; the pricing page has details.
| Text token line | Rate per 1M tokens |
|---|---|
| Input | $1.00 |
| Cached input | $0.05 |
| Cache writes | $1.25 |
| Output | $5.00 |
The cached input line is described as 5% of the uncached input token rate. Because output is priced higher than input, generated text length is likely to influence cost more than prompt length alone in simple comparisons.
The cache-write amounts in the table correspond to 30-minute retention. For Standard cache writes, the listing says $1.25 per million tokens for 30-minute retention and $2.50 for 12-hour retention before long-context adjustments are applied.
This distinction can affect software teams that expect repeated prompts or reusable context. The shorter retention case is shown as the main table value, while the longer retention case is separated with a higher figure.
| Cost situation | Rule from the listing |
|---|---|
| Standard text work | $1.00 input and $5.00 output per 1M tokens, with $0.05 cached input and $1.25 cache writes in the table. |
| Cache retention | $1.25 per million tokens for 30-minute retention; $2.50 for 12-hour retention before long-context adjustments. |
| Prompt over 272K input tokens | Full request at 2x input and cache rates and 1.5x output. |
| Batch or Flex | 50% lower than Standard. |
| Regional processing | 10% premium where available. |
| Fast mode | 2x Standard. |
| Modality | Software-facing support |
|---|---|
| Text | Input and output |
| Image | Input only |
| Audio | Not supported |
| Video | Not supported |
| Endpoint | Path |
|---|---|
| Live | v1/live/sessions |
| Chat Completions | v1/chat/completions |
| Responses | v1/responses |
| Realtime | v1/realtime |
For editors comparing integration options, the endpoint table gives the path names without promising any capability beyond the listed modalities. Text remains the only supported output form, while image enters as an input signal.
Can it output images, audio, or video? No. The text table shows Text as input and output, Image as input only, while Audio and Video are not supported.
Does the cached input price apply automatically? The listed relationship is that cached input is 5% of the uncached input token rate; cache writes are a separate line and depend on retention.
What happens if a prompt is very long? Once it exceeds 272K input tokens, the full request uses 2x input and cache rates and 1.5x output.
Is there a cheaper execution class than Standard? The page says Batch and Flex are 50% lower than Standard.
Which endpoint should a tool-using integration target? The overview states that the Responses API is required for tool calling.
The decision points above come from the listing's capability table, pricing table, modality table, endpoint table, and limit notes. The key identifiers used are GPT-6.1 Terra and gpt-6.1-terra; the price markers are $1 and $5; the context ceiling is a 1,050,000 context window; the output ceiling is 128,000 max output tokens; the knowledge date is Jun 01, 2026.
For a software column, the useful takeaway is not that every table changes, but where the tables intersect: input modality, reasoning controls, tool-call endpoint, and cost multipliers. Those are the four places where a selection decision can be made without adding speculation.