# Model metadata

Copy as Markdown[View as Markdown](/docs/development/guides/agents/model-metadata.md)

***

**Added in** `eventcatalog@3.41.0`

Every agent can declare the LLM it uses through a `model` block in its frontmatter. This gives your team a single place to see which model powers each agent across your entire catalog.

![Agents in the EventCatalog discover view](/assets/images/explore-agents-c758bebd4e459c365a13cd1d552a21b7.png)

## Why track the model?[​](#why-track-the-model "Direct link to Why track the model?")

LLM providers release new model versions, retire old snapshots, and change behavior between releases — often without a corresponding code deployment. Capturing `provider`, `name`, and `version` makes it easy to:

* Audit which agents are running on deprecated or retired snapshots.
* Surface model drift when a provider rolls out a new default.
* Give reviewers the context they need when an agent's output changes unexpectedly.

## Add model metadata[​](#add-model-metadata "Direct link to Add model metadata")

Add a `model` block to your agent's frontmatter:

/agents/FraudReviewAgent/index.mdx (OpenAI example)

```
---
id: FraudReviewAgent
name: Fraud Review Agent
version: 0.0.1

# Optional model metadata describing the LLM this agent runs on
model:
  # The provider or platform powering the model
  provider: OpenAI
  # The model identifier
  name: gpt-4.1
  # The snapshot or API version of the model
  version: "2025-04-14"
---
```

/agents/InventoryRebalancingAgent/index.mdx (Gemini example)

```
---
id: InventoryRebalancingAgent
name: Inventory Rebalancing Agent
version: 0.0.1

# Optional model metadata describing the LLM this agent runs on
model:
  # The provider or platform powering the model
  provider: Gemini
  # The model identifier
  name: gemini-2.5-pro
  # The snapshot or API version of the model
  version: "2025-06-17"
---
```

/agents/ProductContentAgent/index.mdx (Anthropic example)

```
---
id: ProductContentAgent
name: Product Content Agent
version: 0.0.1

# Optional model metadata describing the LLM this agent runs on
model:
  # The provider or platform powering the model
  provider: Anthropic
  # The model identifier
  name: claude-sonnet-4-5
  # The snapshot or API version of the model
  version: "20241022"
---
```

### Model fields[​](#model-fields "Direct link to Model fields")

| Field      | Required | Description                                                                     |
| ---------- | -------- | ------------------------------------------------------------------------------- |
| `provider` | No       | The provider or platform — e.g. `OpenAI`, `Anthropic`, `Gemini`, `Azure OpenAI` |
| `name`     | No       | The model identifier — e.g. `gpt-4.1`, `claude-sonnet-4-5`, `gemini-2.5-pro`    |
| `version`  | No       | The snapshot or API version — e.g. `2025-04-14`, `20241022`                     |

All three fields are optional strings. Use whatever convention your provider uses for model identifiers and snapshot dates.

## Model changes and versioning[​](#model-changes-and-versioning "Direct link to Model changes and versioning")

When you upgrade the model an agent uses, consider whether the behavior change is significant enough to warrant a new agent version. Capturing the new `model.version` in a versioned snapshot (see [Versioning](/docs/development/guides/agents/versioning-and-lifecycle/versioning.md)) gives your team a clear record of when the model changed and who approved it.