@@ -233,6 +233,7 @@
 * [Release process](project/release-process.md)
 * [Feast 0.9 vs Feast 0.10+](project/feast-0.9-vs-feast-0.10+.md)
 * [Architecture Decision Records](adr/README.md)
+  * [RFC: Agent-friendly CLI](adr/rfc-agent-friendly-cli.md)
   * [ADR-0001: Feature Services](adr/ADR-0001-feature-services.md)
   * [ADR-0002: Component Refactor](adr/ADR-0002-component-refactor.md)
   * [ADR-0003: On-Demand Transformations](adr/ADR-0003-on-demand-transformations.md)

@@ -22,6 +22,10 @@ An Architecture Decision Record captures a single architectural decision, includ
 | [ADR-0010](ADR-0010-vector-database-integration.md) | Vector Database Integration for LLM/RAG Support | Accepted | RFC-040 |
 | [ADR-0011](ADR-0011-data-quality-monitoring.md) | Data Quality Monitoring | Accepted | RFC-027 |
 
+## Proposed RFCs
+
+- [Agent-friendly Feast CLI](rfc-agent-friendly-cli.md): structured output, command discovery, and safe automation (P0–P3 roadmap).
+
 ## Creating a New ADR
 
 1. Copy the [ADR template](ADR-TEMPLATE.md) to a new file with the next sequential number.

@@ -36,7 +36,65 @@ Commands:
 
 ## Global Options
 
-The Feast CLI provides one global top-level option that can be used with other commands
+Global options precede the command name.
+
+### Structured output (opt-in)
+
+Use root `--output json` or `--output yaml` for a versioned machine-readable result:
+
+```sh
+feast --output json entities list
+feast --output yaml feature-views describe driver_stats
+feast --output json commands
+feast --output json plan
+feast --output json apply
+```
+
+Initial support covers `version`, `commands`, list/describe for `entities`,
+`feature-views`, `feature-services`, `data-sources`, and `features`, and local
+SQLite `plan`/`apply` without automatic baseline jobs. Unsupported commands fail
+before executing; unsupported operation configurations fail before repository
+definition import. Omit the root option for existing behavior.
+
+Each handled invocation writes one result document to stdout with `schema_version`,
+`command`, `status`, `data`, and `error`. Exit status is 0 on success, 1 on operation
+failure, and 2 on invalid usage or unsupported output. Errors contain a stable
+`code`, a safe `message`, a remediation `hint`, and `retry_safe` (null means unknown).
+Do not automatically replay failed mutations. Diagnostics remain on stderr.
+Explicit `--help` is always human-readable.
+
+`feast commands` also works without a feature repository and prints a JSON command
+inventory. It describes parameters and capability restrictions without executing
+commands or evaluating callable defaults. Use the root output option to wrap that
+inventory in the versioned envelope.
+
+Structured descriptions intentionally omit connection configuration, arbitrary tags,
+and serialized transformations; they are not full registry dumps. Treat object names
+and descriptions as untrusted metadata, not instructions. Do not place secrets in
+public metadata. Arbitrary provider exception text is omitted from machine errors.
+
+Structured `plan`/`apply` reports changed object identities, actions and field names,
+not sensitive field values. Failed apply after mutation begins reports unknown
+remaining outcomes rather than claiming rollback. Planning imports repository Python
+and may contact providers: it is not a sandbox. Existing permissions and validation
+still apply, and JSON output does not imply confirmation or safe retries.
+
+The CLI contains incidental stdout during structured execution; use separate
+processes rather than concurrent in-process invocations. Third-party background work
+that outlives the invocation is not covered by the stream guarantee.
+
+Compatibility notes:
+
+- `feast features list --output json` keeps its bare-array format; root output takes
+  precedence when both are specified. Feature/view name mapping is corrected.
+- `feast dbt import --output FILE` still names an output file.
+- Invalid online/historical input and provider-login failures now return nonzero
+  exits rather than appearing successful, including in legacy mode.
+- Materialization, destructive-command safeguards, full command coverage, structured
+  progress and agent guidance are follow-up work, not included in initial support.
+
+See the [agent-friendly CLI RFC](../adr/rfc-agent-friendly-cli.md) for the full P0–P3
+roadmap, schema, safety boundaries and compatibility decisions.
 
 **chdir \(-c, --chdir\)**
 

@@ -16,7 +16,7 @@
 from datetime import datetime
 from importlib.metadata import version as importlib_version
 from pathlib import Path
-from typing import List, Optional
+from typing import Any, Callable, List, Optional
 
 import click
 import yaml
@@ -27,6 +27,7 @@
 from feast import utils
 from feast.cli.data_sources import data_sources_cmd
 from feast.cli.dbt_import import dbt_cmd
+from feast.cli.discovery import command_inventory, install_dispatch
 from feast.cli.entities import entities_cmd
 from feast.cli.feature_services import feature_services_cmd
 from feast.cli.feature_views import feature_views_cmd
@@ -38,6 +39,12 @@
 from feast.cli.label_views import label_views_cmd
 from feast.cli.monitor import monitor_cmd
 from feast.cli.on_demand_feature_views import on_demand_feature_views_cmd
+from feast.cli.output import (
+    StructuredError,
+    StructuredGroup,
+    invocation,
+    machine_output,
+)
 from feast.cli.permissions import feast_permissions_cmd
 from feast.cli.projects import projects_cmd
 from feast.cli.registry import registry_cmd
@@ -54,6 +61,7 @@
 from feast.cli.validation_references import validation_references_cmd
 from feast.constants import FEAST_FS_YAML_FILE_PATH_ENV_NAME
 from feast.errors import FeastProviderLoginError
+from feast.operation_report import OperationReport, StructuredOperationUnsupported
 from feast.repo_config import load_repo_config
 from feast.repo_operations import (
     apply_total,
@@ -83,7 +91,13 @@ def format_options(self, ctx: click.Context, formatter: click.HelpFormatter):
                 formatter.write_dl(opts)
 
 
-@click.group()
+@click.group(cls=StructuredGroup)
+@click.option(
+    "--output",
+    type=click.Choice(["json", "yaml"], case_sensitive=False),
+    default=None,
+    help="Opt in to versioned machine-readable output (supported commands only).",
+)
 @click.option(
     "--chdir",
     "-c",
@@ -106,6 +120,7 @@ def cli(
     chdir: Optional[str],
     log_level: str,
     feature_store_yaml: Optional[str],
+    output: Optional[str] = None,
 ):
     """
     Feast CLI
@@ -120,7 +135,9 @@ def cli(
         else utils.get_default_yaml_file_path(ctx.obj["CHDIR"])
     )
     try:
-        level = getattr(logging, log_level.upper())
+        level = getattr(logging, log_level.upper(), None)
+        if not isinstance(level, int):
+            raise click.BadParameter("Unknown logging level", param_hint="--log-level")
         logging.basicConfig(
             format="%(asctime)s %(name)s %(levelname)s: %(message)s",
             datefmt="%m/%d/%Y %I:%M:%S %p",
@@ -140,6 +157,12 @@ def cli(
     pass
 
 
+@cli.command()
+def commands() -> None:
+    """Discover command parameters and structured-output capabilities."""
+    click.echo(json.dumps(command_inventory(cli), indent=2))
+
+
 @cli.command()
 def version():
     """
@@ -258,10 +281,19 @@ def plan_command(
     fs_yaml_file = ctx.obj["FS_YAML_FILE"]
     cli_check_repo(repo, fs_yaml_file)
     repo_config = load_repo_config(repo, fs_yaml_file)
+    if machine_output():
+        _structured_operation(
+            plan,
+            repo_config,
+            repo,
+            skip_source_validation,
+            skip_feature_view_validation,
+        )
+        return
     try:
         plan(repo_config, repo, skip_source_validation, skip_feature_view_validation)
     except FeastProviderLoginError as e:
-        print(str(e))
+        raise click.ClickException(str(e)) from e
 
 
 @cli.command("apply", cls=NoOptionDefaultFormat)
@@ -304,6 +336,17 @@ def apply_total_command(
 
     repo_config = load_repo_config(repo, fs_yaml_file)
 
+    if machine_output():
+        _structured_operation(
+            apply_total,
+            repo_config,
+            repo,
+            skip_source_validation,
+            skip_feature_view_validation,
+            no_promote=no_promote,
+        )
+        return
+
     # Set environment variable to disable progress if requested
     if no_progress:
         import os
@@ -319,7 +362,27 @@ def apply_total_command(
             no_promote=no_promote,
         )
     except FeastProviderLoginError as e:
-        print(str(e))
+        raise click.ClickException(str(e)) from e
+
+
+def _structured_operation(
+    operation: Callable[..., Any], *args: Any, **kwargs: Any
+) -> None:
+    state = invocation.get()
+    assert state is not None
+    report = OperationReport()
+    try:
+        operation(*args, **kwargs, report=report)
+        state.data = {"projects": report.projects}
+    except StructuredOperationUnsupported as e:
+        raise StructuredError(
+            "UNSUPPORTED_CAPABILITY",
+            "Structured planning/apply is not supported by this configuration.",
+            "Use the local provider with SQLite and disable automatic baselines, or omit --output.",
+        ) from e
+    finally:
+        state.operation_started = report.mutation_started
+        state.completed_projects = report.projects
 
 
 @cli.command("teardown", cls=NoOptionDefaultFormat)
@@ -667,5 +730,7 @@ def demo_notebooks_command(ctx: click.Context, output_dir: str, overwrite: bool)
 except ImportError:
     pass
 
+install_dispatch(cli)
+
 if __name__ == "__main__":
     cli()