# Use a credential from an agent

> Bind a Credential to a governed Resource and expose only Resource operations to agent code.

Agents normally use Credentials indirectly. A Resource declares a named Credential slot, its Driver interprets the material, and the Agent invokes the Resource operation. This keeps secret bytes outside prompts and agent input.

## Before you begin {#before-you-begin}

- Create or authorize the Credential.
- Deploy a Resource whose Driver declares the required Credential slot.
- Decide whether the Resource and Credential are fixed or selected by tenant, customer, or principal.

## Steps {#steps}

1. Bind the Credential to the Resource's named slot.
2. Bind the Resource to the Agent under a meaningful local name such as `github`.
3. Expose only the required Resource operations as Tools.
4. Grant `resource:invoke`, `credential:use`, and—when scoped—`binding:use` through Policy.
5. Invoke the Agent through an authenticated Channel or platform API.

Conceptually, the relationship is:

```text
Agent tool → Resource operation → Driver → named Credential slot → active encrypted version
```

Agent code receives a Resource handle, not secret material. The Broker resolves and authorizes the Credential at the operation boundary.

## Verify {#verify}

After one successful invocation:

- the Credential detail page should list the Resource under **Where it is used**;
- **Recent activity** should show the injected version and outcome;
- the run identity should pin the Resource, Credential resolution, binding revision, and Policy decisions.

## Troubleshooting {#troubleshooting}

- **CredentialBindingRequired:** the Resource declared a required scoped slot but no assignment exists for the authenticated owner.
- **BindingUseDenied:** Policy denied the selected assignment.
- **CredentialUnavailable:** there is no usable active version.
- **BindingContractMismatch:** a scoped Resource assignment does not match the authored contract.

## Next steps {#next-steps}

For one shared Agent serving multiple owners, continue with [Scoped bindings](/docs/credentials/scoped-bindings.md). For lifecycle operations, read [Credential lifecycle](/docs/credentials/lifecycle.md).