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

# Knowledge Erasure

> Clear, delete, and inspect knowledge with loud, predictable guarantees

Erasure clears an agent's knowledge base between sessions, with clear errors when an adapter can't support an operation.

```python theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
from praisonaiagents import Agent

agent = Agent(name="privacy-aware", instructions="Answer, then clear context between sessions.", knowledge=["policy.md"])
agent.start("Summarise the policy")
agent.knowledge.reset()   # clears the knowledge base between sessions
```

```mermaid theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
graph LR
    subgraph "Knowledge Erasure"
        A[📚 Knowledge] --> B{🔍 Adapter supports op?}
        B -->|Yes| C[✅ Erased]
        B -->|reset unsupported| D[⚠️ Warning no-op]
        B -->|delete_all / history unsupported| E[❌ NotImplementedError]
    end

    classDef input fill:#8B0000,stroke:#7C90A0,color:#fff
    classDef process fill:#F59E0B,stroke:#7C90A0,color:#fff
    classDef success fill:#10B981,stroke:#7C90A0,color:#fff
    classDef warn fill:#6366F1,stroke:#7C90A0,color:#fff

    class A input
    class B process
    class C success
    class D,E warn
```

## Quick Start

<Steps>
  <Step title="Reset the knowledge base">
    ```python theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
    from praisonaiagents import Agent

    agent = Agent(name="assistant", instructions="Answer from the docs", knowledge=["policy.md"])
    agent.start("Summarise the policy")

    # Clear the knowledge base between sessions
    agent.knowledge.reset()
    ```
  </Step>

  <Step title="Delete all scoped memories">
    ```python theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
    # Delete everything for a given scope
    agent.knowledge.delete_all(user_id="user-123")
    ```
  </Step>

  <Step title="Inspect change history">
    ```python theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
    # History is only available on Mem0-backed knowledge
    changes = agent.knowledge.history(memory_id="mem-abc")
    ```
  </Step>
</Steps>

***

## How It Works

`Knowledge` erasure calls route to the underlying `memory` adapter. Unsupported operations fail loudly instead of raising `AttributeError`.

```mermaid theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
sequenceDiagram
    participant User
    participant Knowledge
    participant Adapter

    User->>Knowledge: reset() / delete_all() / history()
    Knowledge->>Adapter: Delegate operation
    alt Adapter supports it
        Adapter-->>Knowledge: Done
        Knowledge-->>User: Result
    else reset() unsupported
        Knowledge-->>User: WARNING no-op
    else delete_all() / history() unsupported
        Knowledge-->>User: NotImplementedError
    end
```

| Operation            | Behaviour when unsupported   |
| -------------------- | ---------------------------- |
| `reset()`            | Logs a `WARNING` and no-ops  |
| `delete_all()`       | Raises `NotImplementedError` |
| `history(memory_id)` | Raises `NotImplementedError` |

***

## Adapter Capabilities

Support differs per adapter — verify against `praisonaiagents/knowledge/adapters/` before relying on an operation.

| Operation      | Chroma                  | SQLite                  | Mongo                   | Mem0 |
| -------------- | ----------------------- | ----------------------- | ----------------------- | ---- |
| `reset()`      | ✅                       | ✅                       | ⚠️ warning + no-op      | ✅    |
| `delete_all()` | ✅                       | ✅                       | ❌ `NotImplementedError` | ✅    |
| `history(id)`  | ❌ `NotImplementedError` | ❌ `NotImplementedError` | ❌ `NotImplementedError` | ✅    |

<Note>
  **Since PraisonAI PR [#4020](https://github.com/MervinPraison/PraisonAI/pull/4020)**, `Knowledge.reset()` warns instead of raising `AttributeError`, and `delete_all()` / `history()` raise `NotImplementedError` on unsupported adapters instead of `AttributeError`. Wrap `history()` and `delete_all()` in try/except when your code should work across adapters.
</Note>

***

## Common Patterns

Guard erasure calls so your code works across adapters:

```python theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
from praisonaiagents import Agent

agent = Agent(name="assistant", instructions="Answer from the docs", knowledge=["policy.md"])

# reset() is always safe — it warns instead of raising
agent.knowledge.reset()

# delete_all() / history() may not be supported
try:
    agent.knowledge.delete_all(user_id="user-123")
except NotImplementedError:
    # Fall back to reset() on adapters without scoped delete
    agent.knowledge.reset()
```

***

## Best Practices

<AccordionGroup>
  <Accordion title="Reset between sessions">
    Call `agent.knowledge.reset()` at the end of a session to clear context for privacy-sensitive workflows. It always succeeds — on adapters without native reset, it warns and no-ops.
  </Accordion>

  <Accordion title="Wrap delete_all() and history()">
    Both raise `NotImplementedError` on adapters that don't support them. Wrap them in try/except so multi-adapter code degrades gracefully.
  </Accordion>

  <Accordion title="Use Mem0 for history">
    Only Mem0-backed knowledge implements `history(memory_id)`. Choose Mem0 when you need an audit trail of memory changes.
  </Accordion>

  <Accordion title="Check logs after upgrade">
    `reset()` now logs a warning when the adapter can't reset. Watch your logs to confirm the tier was actually cleared.
  </Accordion>
</AccordionGroup>

***

## Related

<CardGroup cols={2}>
  <Card title="Knowledge Overview" icon="book" href="/docs/knowledge/overview">
    Load files and documents into an agent's knowledge base.
  </Card>

  <Card title="Knowledge Storage" icon="database" href="/docs/knowledge/storage">
    Configure the storage backend for knowledge.
  </Card>
</CardGroup>