> ## Documentation Index
> Fetch the complete documentation index at: https://wiki.agnes-ai.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Agnes 2.5 Pro Alpha (Deprecated)
> A multimodal reasoning model whose hosted API is deprecated; official open-source weights remain available on Hugging Face.
The Agnes AI hosted API for Agnes 2.5 Pro Alpha is deprecated and is no longer recommended for new integrations. Its official open-source weights remain available on Hugging Face under the Apache 2.0 license.
The hosted `agnes-2.5-pro-alpha` API is deprecated. This page is retained for historical endpoint, parameter, and benchmark reference only. Use the stable `agnes-2.5-pro` model for new API integrations. The open-source model weights are unaffected.
`agnes-2.5-pro-alpha`
Chat Completions: `POST /v1/chat/completions`
Responses: `POST /v1/responses`
Messages: `POST /v1/messages`
Deprecated; migrate to `agnes-2.5-pro`.
Open-source reasoning model with text and image input.
View the official model weights and model card on Hugging Face.
## Overview
Agnes 2.5 Pro Alpha is intended for workloads that need stronger reasoning depth than flash-class models, including complex code tasks, science and math reasoning, long-context understanding, knowledge-intensive Q\&A, and agentic terminal or workflow tasks.
It uses the same base integration pattern as other Agnes text models:
| Item | Value |
| ------------------- | ------------------------------------------------------------------- |
| Base URL | `https://apihub.agnes-ai.com/v1` |
| Endpoint | `POST /v1/chat/completions` |
| Model name | `agnes-2.5-pro-alpha` |
| Input modalities | Text and image URL |
| Output modality | Text |
| Release date | July 24, 2026 |
| Open-source weights | [Hugging Face](https://huggingface.co/Agnes-AI/Agnes-2.5-Pro-Alpha) |
| License | Apache 2.0 |
| Hosted API status | Deprecated |
The official Agnes 2.5 Pro Alpha weights are now open source under Apache 2.0. Artificial Analysis is a third-party benchmark source and may retain older model metadata until its listing is updated.
## Core Capabilities
Suitable for scientific reasoning, knowledge-intensive questions, and multi-step analysis.
Designed for code generation, debugging, refactoring, test generation, and agentic coding workflows.
Handles long documents, structured context, and multi-turn reasoning tasks.
Accepts image URL inputs for visual analysis and multimodal reasoning.
Supports OpenAI-compatible function calling and external tool orchestration.
Supports streaming responses for interactive product experiences.
## Artificial Analysis Results
The following metrics are based on the Artificial Analysis data provided for Agnes 2.5 Pro Alpha.
| Summary Item | Value |
| ---------------------------- | ----------- |
| Intelligence summary rank | `#9 / 153` |
| Price summary rank | `#46 / 153` |
| Cache hit price summary rank | `#8 / 153` |
| Metric | Score |
| ------------------ | ---------: |
| Intelligence Index | `39` |
| GPQA | `87.6%` |
| SciCode | `42.2%` |
| LCR | `63.7%` |
| Omniscience | `-26.3` |
| Accuracy | `32.3%` |
| Non-hallucination | `13.3%` |
| CritPt | `10.9%` |
| HLE | `31.9%` |
| TerminalBench v2.1 | `67.0%` |
| GDPval v2 | `1170 elo` |
| Tau3 | `11.6%` |
View the model profile, summary, and pricing analysis.
Compare Agnes 2.5 Pro Alpha with other listed models.
## API Reference
### Endpoint
```text theme={null}
POST https://apihub.agnes-ai.com/v1/chat/completions
```
### Headers
```bash theme={null}
-H "Authorization: Bearer YOUR_API_KEY"
-H "Content-Type: application/json"
```
### Request Parameters
| Parameter | Type | Required | Description |
| ---------------------- | --------------- | -------- | ------------------------------------------------------------------------------------------------------ |
| `model` | string | Yes | Model name. Use `agnes-2.5-pro-alpha`. |
| `messages` | array | Yes | Conversation messages, including `system`, `user`, and `assistant` messages. |
| `messages[].content` | string / array | Yes | Message content. It can be plain text or an array of content blocks containing `text` and `image_url`. |
| `temperature` | number | No | Controls randomness. Lower values produce more deterministic output. |
| `top_p` | number | No | Controls nucleus sampling. |
| `max_tokens` | number | No | Maximum number of tokens to generate in the response. |
| `stream` | boolean | No | Whether to enable streaming output. |
| `tools` | array | No | Tool definitions for tool-calling workflows. |
| `tool_choice` | string / object | No | Controls whether and how the model uses tools. |
| `chat_template_kwargs` | object | No | Extension field for OpenAI-compatible requests. |
| `thinking` | object | No | Field for enabling Thinking mode in Anthropic-compatible requests. |
## Image URL Input
Agnes 2.5 Pro Alpha supports text and image URL inputs in the same `messages` request.
```json theme={null}
{
"role": "user",
"content": [
{
"type": "text",
"text": "Analyze this architecture diagram and identify possible failure points."
},
{
"type": "image_url",
"image_url": {
"url": "https://example.com/diagram.png"
}
}
]
}
```
## Request Examples
```bash theme={null}
curl https://apihub.agnes-ai.com/v1/chat/completions \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "agnes-2.5-pro-alpha",
"messages": [
{
"role": "system",
"content": "You are a precise technical assistant."
},
{
"role": "user",
"content": "Explain the tradeoffs between optimistic locking and pessimistic locking in distributed systems."
}
],
"temperature": 0.3,
"max_tokens": 1200
}'
```
```bash theme={null}
curl https://apihub.agnes-ai.com/v1/chat/completions \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "agnes-2.5-pro-alpha",
"messages": [
{
"role": "user",
"content": "Review this TypeScript API handler for security issues, explain the risks, and provide a corrected version."
}
],
"temperature": 0.2,
"max_tokens": 2000
}'
```
```bash theme={null}
curl https://apihub.agnes-ai.com/v1/chat/completions \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "agnes-2.5-pro-alpha",
"messages": [
{
"role": "user",
"content": "Create a step-by-step migration plan for moving a monolith to services."
}
],
"stream": true
}'
```
```bash theme={null}
curl https://apihub.agnes-ai.com/v1/chat/completions \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "agnes-2.5-pro-alpha",
"messages": [
{
"role": "user",
"content": [
{
"type": "text",
"text": "Summarize this chart and call out any anomalies."
},
{
"type": "image_url",
"image_url": {
"url": "https://example.com/chart.png"
}
}
]
}
]
}'
```
## Response Format
```json theme={null}
{
"id": "chatcmpl_xxx",
"object": "chat.completion",
"created": 1784899200,
"model": "agnes-2.5-pro-alpha",
"choices": [
{
"index": 0,
"message": {
"role": "assistant",
"content": "..."
},
"finish_reason": "stop"
}
],
"usage": {
"prompt_tokens": 120,
"completion_tokens": 300,
"total_tokens": 420
}
}
```
### Response Fields
| Field | Type | Description |
| --------------------------- | ------- | --------------------------------------- |
| `id` | string | Unique ID of the completion request. |
| `object` | string | Object type, usually `chat.completion`. |
| `created` | integer | Request timestamp. |
| `model` | string | Model used for the request. |
| `choices` | array | List of generated responses. |
| `choices[].message.role` | string | Role of the message sender. |
| `choices[].message.content` | string | Content generated by the model. |
| `choices[].finish_reason` | string | Reason generation stopped. |
| `usage` | object | Token usage information. |
## Responses API
In addition to Chat Completions, this model supports the OpenAI Responses API. Use `input` instead of `messages`.
### Responses endpoint
```text theme={null}
POST https://apihub.agnes-ai.com/v1/responses
```
### Responses request parameters
| Parameter | Type | Required | Description |
| ------------------- | -------------- | -------- | ------------------------------------------------------------------------------------------------- |
| `model` | string | Yes | Model name. Use `agnes-2.5-pro-alpha`. |
| `input` | string / array | Yes | A plain text prompt or an array of structured input messages. |
| `max_output_tokens` | integer | No | Maximum output budget. Use a larger value for reasoning models to avoid an `incomplete` response. |
```bash theme={null}
curl https://apihub.agnes-ai.com/v1/responses \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "agnes-2.5-pro-alpha",
"input": "Explain how autonomous agents use tools.",
"max_output_tokens": 1024
}'
```
```bash theme={null}
curl https://apihub.agnes-ai.com/v1/responses \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "agnes-2.5-pro-alpha",
"input": [
{
"role": "user",
"content": [
{
"type": "input_text",
"text": "Explain how autonomous agents use tools."
}
]
}
],
"max_output_tokens": 1024
}'
```
### Responses output format
```json theme={null}
{
"id": "resp_xxx",
"object": "response",
"status": "completed",
"model": "agnes-2.5-pro-alpha",
"output": [
{
"type": "reasoning",
"summary": []
},
{
"type": "message",
"role": "assistant",
"status": "completed",
"content": [
{
"type": "output_text",
"text": "Autonomous agents use tools to retrieve data and perform actions."
}
]
}
],
"usage": {
"input_tokens": 40,
"output_tokens": 80,
"total_tokens": 120
},
"error": null,
"incomplete_details": null
}
```
| Field | Type | Description |
| ------------------------- | ------------- | ------------------------------------------------------------------- |
| `id` | string | Unique response ID. |
| `object` | string | Object type, usually `response`. |
| `status` | string | Response state, such as `completed` or `incomplete`. |
| `output` | array | Ordered response items, including reasoning and assistant messages. |
| `output[].type` | string | Item type, such as `reasoning` or `message`. |
| `output[].content[].type` | string | Content type. Generated text uses `output_text`. |
| `output[].content[].text` | string | Generated assistant text. |
| `usage` | object | Token usage information. |
| `error` | object / null | Error details when the request fails. |
| `incomplete_details` | object / null | Explains why a response stopped before completion. |
The current response does not include a top-level `output_text` convenience field. Extract generated text from message items where `output[].type` is `message` and `output[].content[].type` is `output_text`.
Reasoning items are optional and can use either `content[].reasoning_text` or `summary[].summary_text`. Token usage field names can also vary by model: support both `input_tokens` / `output_tokens` and `prompt_tokens` / `completion_tokens`.
If `status` is `incomplete`, inspect `incomplete_details` and retry with a larger `max_output_tokens` value. Reasoning models can consume part of the output budget before producing assistant text.
## Messages API
This model also supports the Anthropic-compatible Messages API. Send conversation input in `messages` and authenticate with `x-api-key`.
### Messages endpoint
```text theme={null}
POST https://apihub.agnes-ai.com/v1/messages
```
### Messages headers
```bash theme={null}
-H "x-api-key: YOUR_API_KEY"
-H "anthropic-version: 2023-06-01"
-H "Content-Type: application/json"
```
### Messages request parameters
| Parameter | Type | Required | Description |
| -------------------- | -------------- | -------- | ------------------------------------------------------------------------- |
| `model` | string | Yes | Model name. Use `agnes-2.5-pro-alpha`. |
| `max_tokens` | integer | Yes | Maximum number of output tokens. Use a larger value for reasoning models. |
| `messages` | array | Yes | Conversation messages containing `user` and `assistant` roles. |
| `messages[].role` | string | Yes | Message role. Use `user` or `assistant`. |
| `messages[].content` | string / array | Yes | Plain text or an array of Anthropic-compatible content blocks. |
| `system` | string / array | No | System instruction for the request. |
| `temperature` | number | No | Controls output randomness. |
| `stream` | boolean | No | Whether to return a streaming response. |
### Messages request example
```bash theme={null}
curl https://apihub.agnes-ai.com/v1/messages \
-H "x-api-key: YOUR_API_KEY" \
-H "anthropic-version: 2023-06-01" \
-H "Content-Type: application/json" \
-d '{
"model": "agnes-2.5-pro-alpha",
"max_tokens": 1024,
"system": "You are a helpful AI assistant.",
"messages": [
{
"role": "user",
"content": "Explain how autonomous agents use tools."
}
]
}'
```
### Messages response format
```json theme={null}
{
"id": "msg_xxx",
"type": "message",
"role": "assistant",
"model": "agnes-2.5-pro-alpha",
"content": [
{
"type": "text",
"text": "Autonomous agents use tools to retrieve information and perform actions."
}
],
"stop_reason": "end_turn",
"usage": {
"input_tokens": 290,
"cache_creation_input_tokens": 0,
"cache_read_input_tokens": 0,
"output_tokens": 28
}
}
```
| Field | Type | Description |
| ----------------------------------- | ------- | -------------------------------------------------------------- |
| `id` | string | Unique message ID. |
| `type` | string | Object type, usually `message`. |
| `role` | string | Response role, usually `assistant`. |
| `model` | string | Model used for the request. |
| `content` | array | Ordered response content blocks. |
| `content[].type` | string | Content block type. Generated text uses `text`. |
| `content[].text` | string | Generated assistant text. |
| `stop_reason` | string | Reason generation stopped, such as `end_turn` or `max_tokens`. |
| `usage.input_tokens` | integer | Number of input tokens used. |
| `usage.output_tokens` | integer | Number of output tokens generated. |
| `usage.cache_creation_input_tokens` | integer | Input tokens written to the prompt cache. |
| `usage.cache_read_input_tokens` | integer | Input tokens read from the prompt cache. |
Read generated text from content blocks where `content[].type` is `text`. If `stop_reason` is `max_tokens`, retry with a larger `max_tokens` value.
## Limits and Pricing
The Agnes 2.5 Pro Alpha hosted API is deprecated. The prices below are retained as historical billing records.
| Item | Value |
| ----------------- | -------------------------------------------------------------------------------- |
| Context window | `1M` tokens |
| Max output | `65536` tokens |
| Input modalities | Text, image |
| Output modalities | Text |
| Reasoning | Yes |
| Model weights | Open source: [Hugging Face](https://huggingface.co/Agnes-AI/Agnes-2.5-Pro-Alpha) |
| License | Apache 2.0 |
| Type | USD Price |
| ---------------------------- | ------------------: |
| Input cache hit / Cache Read | `$0.045 / M tokens` |
| Input cache miss / Input | `$0.45 / M tokens` |
| Output | `$0.90 / M tokens` |
The cached-input price is 10% of the regular input-token price. Pricing and availability may vary by account, region, billing configuration, or later pricing updates. Use the Agnes AI platform dashboard as the source of truth for your account.
## Best Practices
Use the stable Agnes 2.5 Pro model for tasks where correctness and multi-step reasoning matter more than raw latency, such as scientific reasoning, complex policy analysis, and long-form technical planning.
Provide the target language, framework, existing code, error messages, expected behavior, and constraints. Ask for root-cause analysis before the patch when debugging complex issues.
Use structured sections, filenames, or document labels inside the prompt so the model can refer to sources and produce traceable conclusions.
## Integration Checklist
Stop using the deprecated hosted `agnes-2.5-pro-alpha` API and migrate to `agnes-2.5-pro`.
If you need self-hosting, the Agnes 2.5 Pro Alpha open-source weights remain available on Hugging Face.
Basic chat completion requests must include `model` and `messages`.
Use publicly accessible `image_url` values for image inputs.
Track cache read, input, and output token usage because this is a paid model.