feat(tool): add tool and validation domain models

examples/tools/custom-tool.yaml

@@ -0,0 +1,40 @@
+# Example: Custom Python tool
+# A simple custom tool that runs inline Python code.
+
+name: local/line-counter
+description: Count lines in a file
+source: custom
+code: |
+  import pathlib
+  path = pathlib.Path(inputs["file_path"])
+  count = len(path.read_text().splitlines())
+  return {"line_count": count}
+
+input_schema:
+  type: object
+  required:
+    - file_path
+  properties:
+    file_path:
+      type: string
+      description: Path to the file to count lines in
+
+output_schema:
+  type: object
+  properties:
+    line_count:
+      type: integer
+
+capability:
+  read_only: true
+  writes: false
+  idempotent: true
+
+resource_slots:
+  - name: target_file
+    resource_type: fs-mount
+    access: read_only
+    description: File system containing the target file
+    binding: contextual
+
+timeout: 60

examples/tools/mcp-tool.yaml

@@ -0,0 +1,53 @@
+# Example: MCP server tool
+# Delegates execution to a tool on an MCP server.
+
+name: devops/docker-build
+description: Build a Docker image via the DevOps MCP server
+source: mcp
+mcp_server: devops-mcp
+mcp_tool_name: docker_build
+
+input_schema:
+  type: object
+  required:
+    - context_dir
+    - image_tag
+  properties:
+    context_dir:
+      type: string
+      description: Docker build context directory
+    image_tag:
+      type: string
+      description: Tag for the built image
+    dockerfile:
+      type: string
+      description: Path to Dockerfile (relative to context_dir)
+      default: Dockerfile
+
+output_schema:
+  type: object
+  properties:
+    image_id:
+      type: string
+    build_log:
+      type: string
+
+capability:
+  read_only: false
+  writes: true
+  write_scope: container-registry
+  checkpointable: false
+  side_effects:
+    - network
+    - container-registry
+  unsafe: false
+  human_approval_required: false
+
+resource_slots:
+  - name: source_repo
+    resource_type: git-checkout
+    access: read_only
+    description: Source code repository for the Docker build
+    binding: contextual
+
+timeout: 600