OpenAI's long-horizon agentic coding flagship in the GPT-5.1 Codex family. Supports compaction to keep very long coding sessions within context, and is served via the OpenAI Responses API.
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| Token Type | Credits | USD Equivalent |
|---|---|---|
| Input Tokens | 2,322.5 | $1.55 |
| Output Tokens | 18,580 | $12.39 |
| Cached Tokens | 232.25 | $0.15 |
* 1,500 credits โ $1 (actual charges may vary based on usage)
curl -X POST "https://api.core.today/llm/openai/v1/responses" \
-H "Content-Type: application/json" \
-H "Authorization: Bearer cdt_your_api_key" \
-d '{
"model": "gpt-5.1-codex-max",
"input": "Migrate this codebase's HTTP layer from callbacks to async/await. Work file by file and keep tests green.",
"max_output_tokens": 8000
}'| Parameter | Type | Required | Default | Description |
|---|---|---|---|---|
model | string | Yes | gpt-5.1-codex-max | Model identifier |
input | string | array | Yes | - | Responses API input: a plain string or an array of input items (messages, tool results) |
instructions | string | No | - | System-level instructions for the run |
max_output_tokens | integer | No | - | Maximum tokens in the response (Responses API field; not max_tokens) |
stream | boolean | No | false | Enable Server-Sent Events streaming |
Responses API request for a large multi-file task
curl -X POST "https://api.core.today/llm/openai/v1/responses" \
-H "Content-Type: application/json" \
-H "Authorization: Bearer cdt_your_api_key" \
-d '{
"model": "gpt-5.1-codex-max",
"input": "Migrate this codebase's HTTP layer from callbacks to async/await. Work file by file and keep tests green.",
"max_output_tokens": 8000
}'POST /llm/openai/v1/responses