> ## Documentation Index > Fetch the complete documentation index at: https://www.truefoundry.com/llms.txt > Use this file to discover all available pages before exploring further. # Using tfy apply > preview and apply changes to your resources using tfy apply ## What is `tfy apply`? `tfy apply` is a CLI command that lets you create or update resources, such as deployments, workspaces, clusters, and provider accounts, by applying a manifest file. A manifest is a YAML file that describes the resource you want to create or update. > **Note:** If you haven't set up the CLI yet, see the [CLI setup guide](/docs/setup-cli). ## Example: Deploying an OpenAI Provider Account Here's a sample manifest for creating an OpenAI provider account. ```yaml lines theme={"dark"} name: openai-account-cli type: provider-account/openai collaborators: - subject: user:gowtham.v@truefoundry.com role_id: provider-account-manager - subject: team:everyone role_id: provider-account-access auth_data: api_key: tfy-secret://truefoundry:openai-group:API_KEY type: api-key integrations: - type: integration/model/openai name: gpt-4 model_id: gpt-4 model_types: - chat cost: value: input: 0.03 output: 0.06 metric: per_1000_tokens - type: integration/model/openai name: gpt-4o model_id: gpt-4o model_types: - chat cost: value: input: 0.0025 output: 0.01 metric: per_1000_tokens ``` ## What is Dry Run? The `--dry-run` flag simulates the apply process without making any changes. This is useful to validate your manifest and see what would happen if you actually applied it. ## What is Show Diff? The `--show-diff` flag, when used with `--dry-run`, displays the differences between your manifest and the currently deployed resources. This helps you review what changes will be made before applying them. ## Previewing Changes Before Applying To see what changes will be made without actually applying them, you can use the following command: ```bash lines theme={"dark"} tfy apply -f .yaml --dry-run --show-diff ``` This will show you a diff of what will change, without updating anything. ## Applying the changes To apply the changes in your manifest, run: ```bash lines theme={"dark"} tfy apply -f .yaml ``` This will actually create or update the resource as described in your YAML file. ## Directory Mode Instead of specifying individual manifest files with `-f`, you can apply all manifests from a directory using the `-d` (or `--dir` / `--directory`) flag. ```bash lines theme={"dark"} tfy apply --dir ./manifests ``` The `-f` and `--dir` flags are mutually exclusive. You must use exactly one of them. ### How Directory Mode Works * All `*.yaml` and `*.yml` files under the specified directory are discovered recursively * Files are automatically sorted by manifest type to respect dependencies (e.g., team is applied before workspace is applied) ### Previewing Directory Changes You can combine directory mode with dry run to preview all changes: ```bash lines theme={"dark"} tfy apply --dir ./manifests --dry-run --show-diff ``` ## Git-Based Diff Mode When working with manifests stored in a git repository, you can use `--diffs-only` to apply only the files that have changed compared to a specific git reference. ```bash lines theme={"dark"} tfy apply --dir ./manifests --diffs-only ``` This compares your working directory against `HEAD` and only applies YAML files that git considers modified or newly added. ### Specifying a Comparison Reference Use `--ref` to compare against a specific commit, branch, or tag instead of `HEAD`: ```bash lines theme={"dark"} tfy apply --dir ./manifests --diffs-only --ref main ``` ```bash lines theme={"dark"} tfy apply --dir ./manifests --diffs-only --ref v1.2.0 ``` The `--ref` flag is only valid when used with `--diffs-only`. ### What Gets Included * **Modified files**: YAML files that have changes compared to the reference * **New files**: Untracked YAML files under the directory are treated as new and included * **Deleted files**: Tracked in a separate set (used with `--sync`) ## Sync Mode The `--sync` flag enables cleanup of resources whose manifest files have been deleted from git. After applying changed manifests, it will delete platform resources that correspond to removed YAML files. ```bash lines theme={"dark"} tfy apply --dir ./manifests --diffs-only --sync ``` The `--sync` flag requires both `--dir` and `--diffs-only` to be set. If a deleted file's content cannot be parsed from the git history, that entry may be skipped during deletion. ## Quick Reference | Flags | Effect | | ---------------------------------------- | --------------------------------------------------------------------------------------------------- | | `-f manifest.yaml` | Apply a single manifest file | | `-f manifest1.yaml -f manifest2.yaml` | Apply multiple manifest files | | `--dir ./manifests` | Apply all YAML files under the directory, sorted by dependency order | | `--dir ./manifests --dry-run` | Apply all YAML files under the directory, sorted by dependency order, but simulate without applying | | `--dir ./manifests --diffs-only` | Apply only git-changed YAML files under the directory (vs HEAD) | | `--dir ./manifests --diffs-only --ref v` | Apply only git-changed YAML files (vs ref v) | | `--dir ./manifests --diffs-only --sync` | Apply changed files, then delete resources for YAML files removed in git |