# Overview

All API routes are Next.js Route Handlers located in `app/api/`. They run server-side and are not exposed to the client as JavaScript.

***

## Base URL

In development: `http://localhost:3000`

***

## Available Endpoints

| Method | Route                                                                                        | Purpose                                                      |
| ------ | -------------------------------------------------------------------------------------------- | ------------------------------------------------------------ |
| `POST` | [`/api/upload`](/contractguard-ai-docs/api-reference/upload.md)                              | Upload and parse a PDF contract                              |
| `POST` | [`/api/audit`](/contractguard-ai-docs/api-reference/audit.md)                                | Analyze a contract with AI                                   |
| `POST` | [`/api/audit-stream`](/contractguard-ai-docs/api-reference/audit-stream.md)                  | Stream audit results in real time (SSE)                      |
| `POST` | [`/api/chat-contract`](/contractguard-ai-docs/api-reference/chat-contract.md)                | Ask questions about a contract                               |
| `POST` | [`/api/review/checkpoint-with-contract`](/contractguard-ai-docs/api-reference/checkpoint.md) | AI review of evidence against contract (reads files locally) |
| `POST` | `/api/review-checkpoint`                                                                     | Fallback AI review based on metadata                         |
| `POST` | `/api/evidence/upload`                                                                       | Upload evidence files (local + Supabase + Pinata)            |
| `POST` | `/api/contracts/upload-pdf`                                                                  | Upload contract PDF after on-chain deploy                    |
| `POST` | `/api/contracts/save-metadata`                                                               | Save contract metadata to Supabase                           |
| `GET`  | `/api/contracts/[pdaAddress]/metadata`                                                       | Retrieve contract metadata from Supabase                     |
| `GET`  | `/api/market/prices`                                                                         | Proxy to FastAPI market price backend                        |
| `GET`  | `/api/demo-pdf`                                                                              | Serve demo PDF from local disk                               |

***

## Common Request Headers

```http
Content-Type: application/json
```

For file upload (`/api/upload`, `/api/evidence/upload`, `/api/contracts/upload-pdf`):

```http
Content-Type: multipart/form-data
```

***

## Common Response Shape

All endpoints return JSON:

```typescript
// Success
{
  success: true,
  data: { ... }       // endpoint-specific payload
}

// Error
{
  success: false,
  error: "Error message describing what went wrong"
}
```

***

## Error Codes

| HTTP Status | Meaning                                            |
| ----------- | -------------------------------------------------- |
| 200         | Success                                            |
| 400         | Bad request — missing or invalid parameters        |
| 500         | Server error — AI call failed, parsing error, etc. |

***

## AI Model Selection

All AI endpoints accept an optional `model` field in the request body to select the QVAC inference tier:

```json
{
  "model": "smart"
}
```

Valid values:

| Tier    | Model        | Notes                                |
| ------- | ------------ | ------------------------------------ |
| `fast`  | Llama 3.2 1B | Fastest, good for development        |
| `smart` | Qwen3 4B     | Balanced, recommended for production |
| `best`  | Qwen3 8B     | Most capable, for complex contracts  |

If omitted, defaults to the `QVAC_MODEL_DEFAULT` environment variable (default: `fast`).


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://contractguard-ai.gitbook.io/contractguard-ai-docs/api-reference/overview.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.