> ## Documentation Index > Fetch the complete documentation index at: https://docs.yafai.in/llms.txt > Use this file to discover all available pages before exploring further. # Skill Manifests > Skill Manifests for Yafai-skills > Manifests are the core of how yafai-skills enables Large Language Models (LLMs) to interact with external tools and services. They act as comprehensive blueprints, defining what a tool can do, how to use it, and what kind of responses to expect. ## What is a Skills Manifest? * Think of a Manifest as a user manual for a specific tool or API, written in a machine-readable format (YAML). * It provides your LLM with all the necessary instructions to: * Understand a tool's capabilities: What actions can it perform? * Learn how to use it: What inputs does each action require? * Interpret results: How should it understand successful responses and errors? * By providing these manifests, yafai-skills allows LLMs to go beyond just generating text, enabling them to execute real-world actions like sending emails, querying databases, or managing tasks. ## Anatomy of a Skills Manifest > Action Manifests are defined in YAML files and follow a clear, hierarchical structure. ```yaml Basic Structure theme={null} name: [Service Name] # A human-readable name for your tool/service description: [Brief description of the service and its purpose] # What does this tool do? auth_header: "[Authorization|Bearer|API-Key|Custom]" # How to authenticate with the service (e.g., Bearer token, API-Key) actions: # A list of specific operations this tool can perform [ActionName]: # A unique, descriptive name for a single action (e.g., 'send_email', 'get_weather') method: [HTTP_METHOD] # The HTTP method (GET, POST, PUT, DELETE, etc.) headers: # Optional: Custom headers required for this action Content-Type: application/json [Optional-Header-Name]: [Optional-Header-Value] base_url: "[https://api.example.com/resource/path]" # The specific endpoint for this action params: # The input parameters required for this action - name: [param_name] # Name of the parameter (e.g., 'query', 'user_id') type: [string|integer|boolean|array|object] # Data type (see "Parameter Types" below) in: [path|query|body|header] # Where the parameter is sent (URL path, query string, request body, header) description: [Parameter description] # What this parameter is for required: [true|false] # Is this parameter mandatory? # Optional: 'enum' or 'items' or 'properties' for complex types (explained below) desc: | # A concise description of what this specific action does (crucial for LLM understanding) [Describe what this action does in one or two lines.] response_template: # How to format the LLM's understanding of success/failure success: | Success response: {{range .results}} - ID: {{.id}} - Example Field: {{.example_field}} {{end}} failure: | Failed to perform action: - Error: {{.error.message}} ``` *** # Defining Parameters > Parameters are the inputs an action needs. yafai-skills supports various data types to accurately represent your API's requirements. ## Simple Parameter Types These are straightforward individual values like below, > string: Text (e.g., "hello world") > integer: Whole numbers (e.g., 123) > boolean: True/False values (e.g., true, false) ```yaml Simple Parameters theme={null} params: - name: user_id type: integer in: path description: Unique identifier of the user. required: true - name: active_only type: boolean in: query description: Filter for active users. required: false ``` ## Complex Parameter Types These allow for structured data inputs like Arrays, Objects, Nested Arrays/Objects etc. ### Object (Structured Data Group) An object parameter groups several related pieces of information, much like a form with multiple fields. Use properties to define the individual fields (and their types, descriptions, and whether they are required) within the object. Objects are typically sent in the body of a POST or PUT request. ```yaml theme={null} params: - name: user_details # Our object parameter type: object in: body description: Detailed information about the user. required: true properties: # Defines fields within 'user_details' as a list - name: first_name type: string description: User's first name. required: true - name: last_name type: string description: User's last name. required: true - name: email type: string format: email # Optional: semantic hint for email format description: User's email address. required: false ``` ### Array (List of Items) An array parameter represents a list of items of the same type. Use items to describe the data type of each element within the array. The items can be simple types (like string, integer) or even complex types (object). ```yaml theme={null} params: - name: product_ids # Our array parameter type: array in: query # Arrays of simple types often in query description: A list of product IDs to retrieve. required: true items: # Each item in items can param with its own param defintion 'product_ids' is an integer - type: integer ``` ### Nested objects and arrays You can combine object and array types to define more complex data structures. Array of Objects: A list where each item in the list is itself a structured object. ```yaml theme={null} params: - name: new_employees # An array of objects type: array in: body description: A list of new employees to onboard. required: true items: # Direct list of properties for EACH object in the array - name: employee_id type: string description: Unique ID of the employee. required: true - name: name type: string description: Full name of the employee. required: true - name: department type: string description: Department the employee belongs to. required: false ``` ### Object with Nested Object An object containing another object as one of its fields. ```yaml theme={null} params: - name: order_request # Our main object type: object in: body description: Details for a new order. required: true properties: # Fields for 'order_request' - name: order_id type: string description: Unique identifier for the order. required: true - name: quantity type: integer description: Number of items in the order. required: true - name: shipping_address # A nested object type: object description: The delivery address for the order. required: true properties: # Fields for 'shipping_address', defined as a list - name: street type: string description: Street address. required: true - name: city type: string description: City name. required: true - name: zip_code type: string description: Postal code. required: true ``` ### Root Body (Entire Request Body) > The root\_body field is a boolean flag (true or false) used exclusively for parameters with in: body. When set to true, it signifies that this particular parameter should represent the entire content of the HTTP request body, rather than being a named field within a larger JSON object. This is useful for APIs that expect the root of their request body to be a raw array or a single complex object without an encapsulating key. Only one parameter per action can have root\_body: true. ```yaml theme={null} params: - name: user_list # This parameter will be the entire body type: array in: body description: A list of user objects to create. required: true root_body: true # This makes 'user_list' the direct JSON array body items: # Define the structure of each user object in the array - name: username type: string description: The user's unique username. required: true - name: email type: string description: The user's email address. required: true ``` ### Enum (Predefined Options) The enum keyword allows you to specify a fixed list of allowed values for string parameters, or for the items within an array of strings. This helps ensure valid inputs and guides the LLM. enum for a string parameter: The priority parameter can only be one of "low", "medium", or "high". ```yaml theme={null} params: - name: priority type: string in: query description: The priority level for the task. required: true enum: - low - medium - high ``` ### Enum for items in an array of strings: The tags array can contain multiple strings, but each string must be one of the specified categories. ```yaml theme={null} params: - name: tags type: array in: body description: A list of relevant tags. required: false items: # Each item in the 'tags' array type: string enum: # Each tag string must be one of these - marketing - sales - development - support ``` ***