> ## Documentation Index
> Fetch the complete documentation index at: https://docs.hasmcp.com/llms.txt
> Use this file to discover all available pages before exploring further.

# How does HasMCP use JMESPath Pruning to reshape JSON responses?

> Applying strict structural filters natively to optimize payloads securely.

# JMESPath Pruning

HasMCP integrates the **JMESPath** query engine directly into the routing middleware of every Provider Tool and Resource dynamically.

Whenever a tool executes, the external API server returns a raw payload. Instead of returning that massive payload back to the originating MCP Client, HasMCP temporarily buffers the JSON response natively.

The platform then executes your predefined JMESPath query string against the buffered `JSON` securely.

### Example Pruning Flow

Assume a provider API returns this large payload structurally:

```json theme={null}
{
 "request_id": "abc-123",
 "metadata": { "page": 1, "has_more": false },
 "users": [
 { "internal_db_id": 991, "first_name": "Alice", "secret_hash": "xy$" },
 { "internal_db_id": 992, "first_name": "Bob", "secret_hash": "z1!" }
 ]
}
```

If you apply the specific HasMCP JMESPath definition:
`users[*].{name: first_name}`

The LLM exclusively receives:

```json theme={null}
[
 { "name": "Alice" },
 { "name": "Bob" }
]
```

This transforms a heavy integration object into exactly the semantic value the agent fundamentally desires.