Features

Response Healing

Automatically fix malformed JSON responses

The Response Healing plugin automatically validates and repairs malformed JSON responses from AI models. When models return imperfect formatting – missing brackets, trailing commas, markdown wrappers, or mixed text – this plugin attempts to repair the response so you receive valid, parseable JSON.

Overview

Response Healing provides:

  • Automatic JSON repair: Fixes missing brackets, commas, quotes, and other syntax errors
  • Markdown extraction: Extracts JSON from markdown code blocks

How It Works

The plugin activates for non-streaming requests when you use response_format with type: "json_schema", and include the response-healing plugin in your plugins array. See the Complete Example below for a full implementation.

What Gets Fixed

The Response Healing plugin handles common issues in LLM responses:

JSON Syntax Errors

Input: Missing closing bracket

{"name": "Alice", "age": 30

Output: Fixed

1{"name": "Alice", "age": 30}

Markdown Code Blocks

Input: Wrapped in markdown

```json
{"name": "Bob"}
```

Output: Extracted

1{"name": "Bob"}

Mixed Text and JSON

Input: Text before JSON

Here's the data you requested:
{"name": "Charlie", "age": 25}

Output: Extracted

1{"name": "Charlie", "age": 25}

Trailing Commas

Input: Invalid trailing comma

{"name": "David", "age": 35,}

Output: Fixed

1{"name": "David", "age": 35}

Unquoted Keys

Input: JavaScript-style

{name: "Eve", age: 40}

Output: Fixed

1{"name": "Eve", "age": 40}

Complete Example

1const response = await fetch('https://openrouter.ai/api/v1/chat/completions', {
2  method: 'POST',
3  headers: {
4    Authorization: 'Bearer {{API_KEY_REF}}',
5    'Content-Type': 'application/json',
6  },
7  body: JSON.stringify({
8    model: '{{MODEL}}',
9    messages: [
10      {
11        role: 'user',
12        content: 'Generate a product listing with name, price, and description'
13      }
14    ],
15    response_format: {
16      type: 'json_schema',
17      json_schema: {
18        name: 'Product',
19        schema: {
20          type: 'object',
21          properties: {
22            name: {
23              type: 'string',
24              description: 'Product name'
25            },
26            price: {
27              type: 'number',
28              description: 'Price in USD'
29            },
30            description: {
31              type: 'string',
32              description: 'Product description'
33            }
34          },
35          required: ['name', 'price']
36        }
37      }
38    },
39    plugins: [
40      { id: 'response-healing' }
41    ]
42  }),
43});
44
45const data = await response.json();
46const product = JSON.parse(data.choices[0].message.content);
47// The plugin attempts to repair malformed JSON syntax
48console.log(product.name, product.price);

Limitations

Non-Streaming Requests Only

Response Healing only applies to non-streaming requests.

Will not repair all JSON

Some malformed JSON responses may still be unrepairable. In particular, if the response is truncated by max_tokens, the plugin will not be able to repair it.